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Цитировать2013
July 14 - LADEE - Minotaur V - MARS LP-0B

ЦитироватьNASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) Mission is making great progress towards its 2013 launch to explore the lunar environment. Work is being completed in parallel in five major areas: the radiator panel, the main structure of the spacecraft, the propulsion system, the instruments, and the launch vehicle.

The radiator panel is a flat octagonal metal panel that sits at the top of the spacecraft and holds almost all of the electronics, sensors, and power controls for the rest of the satellite. It is almost a small spacecraft all on its own; so integrating it is a major step for the LADEE Mission. Engineers at NASA's Ames Research Center, Moffett Field, Calif., have pieced together the radiator panel with the avionics and power control unit, the battery, the star tracker, the inertial measurement unit, one of the two omni-antennas that allow us to command the spacecraft, the medium-gain antenna used to transmit science data to the ground, and a version of the flight control software. Other important components still to come are the communications transponder and two larger science instruments - the Neutral Mass Spectrometer (NMS), led by Paul Mahaffy at NASA's Goddard Space Flight Center, Greenbelt, Md., and the Lunar Laser Communications Demonstration (LLCD) technology demonstration led by NASA Goddard and built by MIT Lincoln Labs.

The main spacecraft structure is a lightweight, yet extremely strong, metal composite frame that holds everything together. It will carry four reaction wheels to help steer the spacecraft, along with solar arrays that will help generate power to this structure. Before NASA engineers begin integrating it, the structure has to be tested to make sure it is strong enough for the launch loads. During the tests, the structure was placed on a special table designed to intentionally put the structure through rigorous conditions and test its strength; that's when we encountered a problem - the test table gave an unexpected, big jolt to the structure. Amazingly, the structure held up to the jolt, but as a precaution, we switched to a second structure that had already been built for just this type of contingency. That second structure is now in strength testing and soon will go through a "bake-out," which removes possible contaminants from it. Meanwhile, a big electrical harness that attaches to the main structure and carries power from the solar arrays to the radiator panel, as well with commands to the propulsion system, is assembled and has already completed its own bake-out.

The propulsion system, which will be used to travel to the moon and go into orbit around it to conduct science observations, completed its bake-out in May. Engineers then inspected the alignment of its thrusters and exercised its functions with simulated commands. Everything looks good, so we will soon begin to integrate it with the rest of the spacecraft at NASA Ames..

While the spacecraft is being tested and assembled, the science teams have been completing their work on the LADEE instruments. As each instrument is finished, it goes through a pre-shipment, or "pre-ship," review to look at all of its test data and verification documentation, and approve its delivery for integration with the spacecraft. So far, the Lunar Dust EXperiment (LDEX) instrument led by Mihaly Horanyi at the Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colo., is all done, having wrapped up its pre-ship review. The UltraViolet Spectrometer (UVS), led by Tony Colaprete at NASA Ames, is following closely behind. Because these two science instruments will be integrated onto the radiator panel, they need to be completed soon. The NMS and the LLCD are still being tested and are scheduled to arrive in the fall.

Finally, Orbital Sciences Corp., is making progress on its design reviews of the Minotaur V launch vehicle that will lift LADEE into space. This month at NASA's Wallops Flight Facility's launch complex in Virginia, a team performed a Launch Vehicle Pathfinder. This is an important exercise that involved a large part of the LADEE team, to practice bringing the launch vehicle segments together at the launch range and stacking everything together as if preparing for the launch. This exercise demonstrated all of the transportation steps work, the equipment is ready, and that all the many parts fit together properly.

ЦитироватьNASA Picks Loral for $230M Laser Com Demo

ЦитироватьPARIS — NASA is investing $230 million in an experiment to test laser optical communications between a geostationary-orbiting satellite and a NASA ground terminal in the United States in an unusual hosted-payload contract with satellite builder Space Systems/Loral (SS/L), NASA and SS/L said.

The 175-kilogram Laser Communications Relay Demonstration (LCRD) terminal, now in development at NASA's Goddard Space Flight Center, will be placed aboard a yet-unselected commercial telecommunications satellite that Palo Alto, Calif.-based SS/L hopes to have ready for launch as soon as 2016.

The LCRD terminal would permit high-speed communication of data between the satellite and a NASA-developed ground terminal to be located in the western United States, meaning that whatever commercial satellite SS/L finds for the experiment will need to have a look angle over the United States. NASA has said it is tentatively planning LCRD ground stations in Hawaii and Southern California, taking advantage of work being done for NASA's Lunar Atmosphere Dust Environment Explorer (LADEE) mission to lunar orbit scheduled for 2013.

A supplemental LADEE payload will test laser links between lunar orbit and Earth. The LADEE laser terminal is being built by MIT Lincoln Laboratory, a federally funded research and development center in Lexington, Mass.

LCRD will be NASA's first hosted-payload arrangement. Unlike most hosted-payload contracts, in which a satellite owner negotiates with the owner of the hosted payload, NASA has contracted with SS/L to manage the entire process, meaning SS/L will find a suitable commercial customer and negotiate contract terms with the customer within a NASA-fixed budget that is paid to SS/L, according to Michael Weiss, LCRD project manager at Goddard Space Flight Center.

That will mean SS/L will be responsible for compensating the satellite owner for the on-board power — 600 watts — that the laser terminal requires, and for a share of the launch costs.

In an April 12 interview, Weiss said NASA would like to operate the LCRD for two years. He said NASA received several bids for the contract before settling on the SS/L bid.

Given the normal two- to three-year cycle of satellite production, it is likely that the satellite has not yet been contracted. In a statement, SS/L said that the optical module and the ground stations that will communicate with it are still in development, and that SS/L "will work with its commercial customers to identify an appropriate host satellite for the demonstration."

In addition to being the most successful supplier of commercial telecommunications satellites in recent years among U.S. builders, SS/L has specialized in large, high-power spacecraft — 20 kilowatts of on-board power is not uncommon — that presumably would find it easier to accommodate the LCRD than a smaller or lower-power spacecraft.

Most commercial telecommunications satellites are launched aboard European or Russian rockets, a market reality that could pose difficulties for NASA if it views hosted payloads as a promising new avenue to test technology without paying for an entire satellite and launch. Current U.S. government policy prohibits the use of a non-U.S. vehicle to launch U.S. government hardware if a U.S. alternative is available, unless the mission receives a specific waiver.

But Weiss said the LCRD mission may not need to seek a waiver. He said the agency is formulating a hosted-payload policy that reflects the new hosted-payload opportunities for which NASA is not the host agency.

The use of laser terminals for satellite communications — both between satellites in orbit and between satellites and ground terminals — has been the focus of much investment in Europe, but less so in the United States.

The French and German governments have sponsored laser communications terminals to fly aboard a geostationary-orbiting data-relay satellite that communicated with low-orbiting Earth observation spacecraft carrying similar terminals. More recently, Germany's Tesat Spacecom of Backnang, Germany, has sold laser terminals for use by the 19-nation European Space Agency (ESA) and the 27-nation European Union as part of their Global Monitoring for Environment and Security (GMES) program.

ESA has contracted with Astrium Services of Europe to manage a data-relay service that will use laser terminals on two geostationary-orbiting satellites to speed Earth observation data delivery to ground users from low-orbiting GMES satellites.

Tesat had hoped that a large U.S. government demand for laser terminals would follow the successful use of laser terminals to exchange data between the German government's TerraSAR-X radar Earth observation satellite and the U.S. Missile Defense Agency's Near Field Infrared Experiment, or NFIRE, missile-warning satellite. TerraSAR-X and NFIRE, each equipped with a Tesat-built laser communications terminal, exchanged reproducible data at speeds of 5.5 gigabits per second for several months in 2008 following a bilateral U.S.-German government agreement, according to Tesat.

Despite a Tesat agreement with Fairfax, Va.-based General Dynamics Advanced Information Systems to promote the Tesat technology in the United States, the U.S. government demand has not materialized, and Tesat has focused on European government programs.

Laser communications have the advantage of operating in a section of the electromagnetic spectrum whose frequencies are not regulated by the International Telecommunication Union, a United Nations affiliate.

http://www.spacenews.com/civil/120410-loral-host-payload-nasa-lasercom.html

ЦитироватьLADEE Project Manager Update
04.09.12

ЦитироватьNASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) has received its integrated propulsion system that will enable the spacecraft to reach the moon. Achieving this milestone means the LADEE observatory is one step closer to launching its 2013 mission to explore the lunar environment.

The LADEE propulsion system, built by Space Systems/Loral, Palo Alto, Calif., features a commercially-proven technology. The propulsion system is a variant of the mission critical capabilities used for many years on geostationary satellites to provide television, radio, broadband internet, meteorology and other services.

The LADEE team now has most of the flight hardware components available, and has entered the spacecraft's integration phase. During this phase, the LADEE team will attach hardware components to the various parts of the spacecraft structure, starting with the top radiator panel. This panel contains most of the spacecraft's active electronic systems, except the propulsion system.

As each component is attached, it is tested to verify it was connected and works properly. So far, the team has attached a harness for the electrical wiring and a component to power up the spacecraft, and is preparing to attach the flight battery.

Strength testing of the modular common bus sections - the main super-structure of the spacecraft - built by Vanguard Space Technologies, San Diego, Calif., is about to begin. The bus will be fitted with models of all of the components, so that it can be tested to ensure it is strong enough to handle the rigors of launch. When all of the components of the radiator panel have been integrated and tested, then the panel will be attached to the main structure, along with the integrated propulsion system to complete the spacecraft.

While the spacecraft is being completed, the science teams will finish work on the LADEE instruments. After the team has a completed the spacecraft and instruments, they all will come together and form the LADEE observatory.

http://www.nasa.gov/mission_pages/LADEE/news/2012-04-09-pm_update.html

ЦитироватьSS/L Propels To NASA... The LADEE Checks For Moon Dust

ЦитироватьMarch 15, 2012

[SatNews] Delivery comes ahead of schedule, next stop the moon...

Space Systems/Loral (SS/L) (NASDAQ: LORL), a leading provider of commercial satellites, today announced that it completed on time delivery of a new propulsion system to NASA. The propulsion system for the Lunar Atmosphere Dust Environment Explorer (LADEE) spacecraft was delivered to NASA Ames Research Center, Moffett Field, California, on Thursday, March 8 following successful completion of the final delivery reviews and sign-off.

"Designing spacecraft systems and teaming with commercial manufacturers is helping the NASA Ames-led LADEE project meet demand for lower-cost approaches to science missions," said Stevan Spremo, deputy project manager for LADEE at NASA Ames.

Photos of the LADEE propulsion system after it was delivered to NASA Ames. NASA Ames/Dominic Hart. More SS/L LADEE information is available here.

The LADEE mission to collect lunar dust and study the moon's atmosphere is key to helping researchers plan for future exploration. The propulsion system, which SS/L delivered, will enable LADEE to reach the moon. Using SS/L to provide the system leverages the capability of commercially proven technology for U.S. Government missions.

"In this era of fiscal constraint it is important for the commercial sector to share our extensive heritage and capabilities with government organizations such as NASA," said John Celli, president of Space Systems/Loral. "We have enjoyed teaming with our neighbors here in Northern California, who have designed a very versatile spacecraft platform for unmanned space exploration, and we stand ready to provide future support as needed."

NASA's LADEE spacecraft is a small observatory that will orbit the moon to determine the global density, composition, and time variability of the lunar atmosphere before it is perturbed by further human activity. Its secondary mission will be testing a new spacecraft architecture called the Modular Common Bus, which is being developed by NASA as a flexible, low cost, spacecraft for both orbiting and landing on the moon and other deep space targets. LADEE also will carry an experimental payload that will demonstrate the capability of long distance laser communications.

The LADEE propulsion system built by Space Systems/Loral is a variant of the mission critical systems used over many years on the geostationary satellites that the company provides for television, radio, broadband Internet, meteorology and a host of other services. Space Systems/Loral has more commercial satellite transponders on orbit than any other manufacturer and has built the world's highest capacity broadband satellites. Currently there are 67 SS/L-built satellites orbiting Earth.

http://www.satnews.com/cgi-bin/story.cgi?number=622081249

Цитироватьhttp://www.ssloral.com/html/pressreleases/pr20120314.html

(https://img.novosti-kosmonavtiki.ru/65652.jpg) (http://www.ssloral.com/images/pressrel/ladee/ACD12-0039-023.jpg)

(https://img.novosti-kosmonavtiki.ru/65653.jpg) (http://www.ssloral.com/images/pressrel/ladee/ACD12-0039-022.jpg)

ЦитироватьОпубликовано 01.07.2013
 
 NASA Ames' Lunar Atmosphere and Dust Environment Explorer (LADEE) is a robotic mission that will orbit the moon to gather detailed information about the lunar atmosphere, conditions near the surface and environmental influences on lunar dust.

LADEE's scheduled Sep. 6, 2013, launch will mark several firsts. It will be the first payload to launch on a U.S. Air Force Minotaur V rocket integrated by Orbital Sciences Corp., and the first deep space mission to launch from NASA's Goddard Space Flight Center's Wallops Flight Facility.

Credit: NASA Ames/Dana Berry
Note: Animation is silent with no audio/music track included.

For more information about the LADEE mission, please visit http://www.nasa.gov/LADEE (http://www.nasa.gov/LADEE)
For more information about NASA Ames, please visit http://www.nasa.gov/ames (http://www.nasa.gov/ames)

http://youtu.be/Wge0R-T_xBI (http://youtu.be/Wge0R-T_xBI)

ЦитироватьОпубликовано 07.07.2013

http://www.kickstarter.com/projects/a...

NASA Ames' Lunar Atmosphere and Dust Environment Explorer (LADEE) is a robotic mission that will orbit the moon to gather detailed information about the lunar atmosphere, conditions near the surface and environmental influences on lunar dust.

LADEE's scheduled Sep. 5, 2013, launch will mark several firsts. It will be the first payload to launch on a U.S. Air Force Minotaur V rocket integrated by Orbital Sciences Corp., and the first deep space mission to launch from NASA's Goddard Space Flight Center's Wallops Flight Facility.

Credit: NASA Ames/Dana Berry
Note: Animation is silent with no audio/music track included.

For more information about the LADEE mission, please visit http://www.nasa.gov/LADEE
For more information about NASA Ames, please visit http://www.nasa.gov/ames

http://youtu.be/iAz_xHUe168 (http://youtu.be/iAz_xHUe168)

ЦитироватьОпубликовано 11.07.2013  

NASA Ames' Lunar Atmosphere and Dust Environment Explorer (LADEE) is a robotic mission that will orbit the moon to gather detailed information about the lunar atmosphere, conditions near the surface and environmental influences on lunar dust.

LADEE's scheduled Sep. 6, 2013, launch will mark several firsts. It will be the first payload to launch on a U.S. Air Force Minotaur V rocket integrated by Orbital Sciences Corp., and the first deep space mission to launch from NASA's Goddard Space Flight Center's Wallops Flight Facility.

Release Date: 11 July 2013

Credit: NASA Ames/Dana Berry
Note: Animation is silent with no audio/music track included.

For more information about the LADEE mission, please visit http://www.nasa.gov/LADEE
For more information about NASA Ames, please visit http://www.nasa.gov/ames

http://youtu.be/nfN4EVjrrzg (http://youtu.be/nfN4EVjrrzg)

Цитировать"Тесты на спутнике LADEE были успешные. Нашa наземная станция будет общаться вместе с двух наземных станций НАСА с лунного спутника LADEE. Поэтому мы хотим продемонстрировать, что оптическая связь для будущих миссий на Марсе и другие направления в солнечной системе является готовым к использованию" - сказал Зоран Sodnik, руководитель ЕКА -Projekts Lunar Optical Communication Link.

Лазерные системы связи в средней инфракрасной областях может быть путь в будущее для передачи больших объемов данных с спутники на орбите Земли, Марса или даже более далекие планеты. Эти системы являются легче, меньше и более энергоэффективными, чем используемые в настоящее время радио систем, что приводит к нижней ожидания согласно расходы Миссии и будут созданы возможности для новых инструментов научного Совета.
Скорость более чем 600 мегабит данных в секунду.

ЦитироватьA brand new Minotaur IV rocket is scheduled to launch for the first time from Wallops Flight Facility on September 7th at 03:27 UTC. This vehicle will carry NASA's LADEE (Lunar Atmosphere and Dust Environment Explorer) spacecraft to the Moon.

This video shows animation of the flight profile the rocket will take.

http://www.youtube.com/watch?v=zMt-CQPYt14 (http://www.youtube.com/watch?v=zMt-CQPYt14)

ЦитироватьRELEASE 13-265
NASA Prepares for First Virginia Coast Launch to Moon

In an attempt to answer prevailing questions about our moon, NASA is making final preparations to launch a probe at 11:27 p.m. EDT Friday, Sept. 6, from NASA's Wallops Flight Facility on Wallops Island, Va.

The small car-sized Lunar Atmosphere and Dust Environment Explorer (LADEE) is a robotic mission that will orbit the moon to gather detailed information about the structure and composition of the thin lunar atmosphere and determine whether dust is being lofted into the lunar sky. A thorough understanding of these characteristics of our nearest celestial neighbor will help researchers understand other bodies in the solar system, such as large asteroids, Mercury, and the moons of outer planets.

"The moon's tenuous atmosphere may be more common in the solar system than we thought," said John Grunsfeld, NASA's associate administrator for science in Washington. "Further understanding of the moon's atmosphere may also help us better understand our diverse solar system and its evolution."

The mission has many firsts, including the first flight of the Minotaur V rocket, testing of a high-data-rate laser communication system, and the first launch beyond Earth orbit from the agency's Virginia Space Coast launch facility.

LADEE also is the first spacecraft designed, developed, built, integrated and tested at NASA's Ames Research Center in Moffett Field, Calif. The probe will launch on a U.S. Air Force Minotaur V rocket, an excess ballistic missile converted into a space launch vehicle and operated by Orbital Sciences Corp. of Dulles, Va.

LADEE was built using an Ames-developed Modular Common Spacecraft Bus architecture, a general purpose spacecraft design that allows NASA to develop, assemble and test multiple modules at the same time. The LADEE bus structure is made of a lightweight carbon composite with a mass of 547.2 pounds -- 844.4 pounds when fully fueled.

"This mission will put the common bus design to the test," said Ames Director S. Pete Worden. "This same common bus can be used on future missions to explore other destinations, including voyages to orbit and land on the moon, low-Earth orbit, and near-Earth objects."

Butler Hine, LADEE project manager at Ames, said the innovative common bus concept brings NASA a step closer to multi-use designs and assembly line production and away from custom design. "The LADEE mission demonstrates how it is possible to build a first class spacecraft at a reduced cost while using a more efficient manufacturing and assembly process," Hine said.

Approximately one month after launch, LADEE will begin its 40-day commissioning phase, the first 30 days of which the spacecraft will be performing activities high above the moon's surface. These activities include testing a high-data-rate laser communication system that will enable higher rates of satellite communications similar in capability to high-speed fiber optic networks on Earth.

After commissioning, LADEE will begin a 100-day science phase to collect data using three instruments to determine the composition of the thin lunar atmosphere and remotely sense lofted dust, measure variations in the chemical composition of the atmosphere, and collect and analyze samples of any lunar dust particles in the atmosphere. Using this set of instruments, scientists hope to address a long-standing question: Was lunar dust, electrically charged by sunlight, responsible for the pre-sunrise glow above the lunar horizon detected during several Apollo missions?

After launch, Ames will serve as a base for mission operations and real-time control of the probe. NASA's Goddard Space Flight Center in Greenbelt, Md., will catalogue and distribute data to a science team located across the country.

NASA's Science Mission Directorate in Washington funds the LADEE mission. Ames manages the overall mission. Goddard manages the science instruments and technology demonstration payload, the science operations center and provides overall mission support. Wallops is responsible for launch vehicle integration, launch services and operations. NASA's Marshall Space Flight Center in Huntsville, Ala., manages LADEE within the Lunar Quest Program Office.

For more information about the LADEE mission, visit:

http://www.nasa.gov/ladee

ЦитироватьМОСКВА, 5 сен — РИА Новости. Лунный орбитальный аппарат НАСА LADEE прошел предстартовые процедуры и готов к запуску — чуть более чем через сутки ракета "Минотавр-5" понесет его к Луне, где в течение трех месяцев он будет исследовать лунную атмосферу, окололунную пыль, а также впервые опробует на этой дистанции лазерную линию связи.

Новое открытие Луны

Проект LADEE (Lunar Atmosphere and Dust Environment Explorer) общей стоимостью 280 миллионов долларов стал одним из элементов программы НАСА Lunar Quest — первой большой программы исследования Луны со времен "Аполлонов", благодаря которой представления ученых о спутнике Земли в последние годы существенно изменились.

Исследования с помощью зондов LRO и LCROSS, а также индийского аппарата "Чандраян", в частности, показали, что Луна вовсе не сухой мир, как считалось ранее, что у лунных полюсов, в вечно затененных кратерах сосредоточены гигантские запасы водяного льда и других летучих веществ. Зонды GRAIL впервые составили точную гравитационную карту Луны и выяснили, что лунные породы содержат в себе гораздо больше пустот, чем считалось ранее.
Зонд LADEE, продолжит открывать Луну заново. "С LRO, который еще работает на окололунной орбите, мы исследовали значительную часть поверхности Луны, с помощью зондов GRAIL мы начали исследовать ее недра, а теперь, с LADEE, мы начинаем исследовать таинственную лунную атмосферу", — сказал журналистам заместитель руководителя НАСА Джон Грансфельд (John Grunsfeld).

Сумеречные лучи и левитирующая пыль

Главная задача аппарата — исследование газопылевой оболочки Луны. Ее давление в триллионы раз меньше нормального атмосферного давления на Земле. Если в одном кубическом сантиметре земной атмосферы находится десятки триллионов молекул, то в лунной — около 10 тысяч. Примерно такую же плотность имеет земная атмосфера на высоте орбиты МКС, то есть на высоте около 400 километров. В этом самом внешнем слое земной атмосферы, который называется экзосферой, молекулы газов почти не взаимодействуют друг с другом.

Лунная газовая оболочка состоит в основном из атомов гелия, захваченных из солнечного ветра, атомов аргона, натрия и некоторых других элементов, возникающих при распаде радиоактивных веществ в лунном грунте, а также "выбитых" из него ударами микрометеоритов и заряженных частиц.

С лунной атмосферой связаны загадочные сумеречные лучи, которые наблюдали еще астронавты с борта "Аполлона-17". Незадолго перед восходом Солнца над горизонтом Луны возникало яркое зарево, из которого исходили лучи. Эту картину зарисовал в своем блокноте командир "Аполлона" Юджин Сернан, и тогда это явление поставило ученых в тупик.

Как считают ученые, в лучах восходящего Солнца могла сиять лунная пыль, которая выбрасывается над поверхностью и левитирует над ней, за счет электростатического заряда. "Заряжает" частицы пыли ультрафиолетовая радиация.

С помощью масс-спектрометра NMS, ультрафиолетового спектрометра UVS и прибора для изучения пыли LDEX зонд определит состав и плотность лунной атмосферы, измерит, как эти параметры меняются со временем (плотность лунной атмосферы падает примерно в 100 раз после начала лунной ночи). Ученые рассчитывают точно определить, как падения метеоритов влияют на газопылевую оболочку, а также выяснить, как ведет себя "электрифицированная" пыль. Результаты исследования помогут понять, имеет ли смысл открывать на Луне обсерватории, а также узнать, какое влияние может оказать лунная атмосфера на будущих колонистов.

Лазерное шоу

С помощью LADEE ученые впервые попытаются установить лазерную линию связи между Луной и Землей. В течение первых 30 дней после старта прибор LLCD отправит на Землю мощный лазерный луч и попытается принять ответный луч с Земли. НАСА нуждается в более быстром канале связи, чем радиосвязь. Лазерная связь обеспечивает скорость передачи данных в шесть раз выше, чем радиоканал — до 600 мегабит в секунду. Кроме того, она требует значительно меньшей мощности, чем радиосвязь.

Ученые рассчитывают в случае успеха эксперимента снабжать высокоскоростными лазерными передатчиками другие автоматические станции.

В этой миссии помимо первой попытки создать оптический канал передачи данных на таком большом расстоянии есть еще много слов "первый". Это, в частности, первый запуск аппарата за пределы околоземной орбиты с космодрома на острове Уоллопс — эта стартовая площадка находится в штате Виргиния, и взлет ракет там виден даже в Вашингтоне. Кроме того, это первый запуск новой пятиступенчатой ракеты "Минотавр-5" (Minotaur V), созданной корпорацией Orbital.

ЦитироватьWEDNESDAY, SEPTEMBER 4, 2013
 Mission managers today gave approval to continue launch preparations for Friday's flight of a Minotaur 5 rocket from Virginia with NASA's moon-bound LADEE spacecraft. The $280 million mission is scheduled to blast off at 11:27 p.m. EDT Friday (0327 GMT Saturday) from launch pad 0B at the Mid-Atlantic Regional Spaceport at NASA's Wallops Flight Facility on Virginia's Eastern Shore.
Officials met today for the launch readiness review to discuss the status of the launch vehicle, the LADEE spacecraft, ground systems and the weather outlook for Friday night's four-minute launch window.
No problems were reported, according to George Diller, a NASA spokesperson.
The weather forecast calls for favorable conditions Friday night, with temperatures in the 60s Fahrenheit. There is just a 5 percent chance of weather violating launch criteria due to cloudiness moving in from offshore, Diller said.
Officials completed a mission dress rehearsal this afternoon to practice countdown procedures ahead of Friday's activities.
The 80-foot-tall, five-stage Minotaur 5 rocket is making its first flight. The launch of LADEE also marks the first lunar mission to launch from Wallops.
The Lunar Atmosphere and Dust Environment Explorer is beginning a 160-day mission to study the composition and dynamics of the moon's tenuous atmosphere.
The late-night launch will be visible along the U.S. East Coast, with viewing opportunities available from South Carolina to New York and inland to the Appalachians.
If you're in the area and want to see the launch, check out this map (http://spaceflightnow.com/minotaur/ladee/visibility.html) showing its visibility, weather permitting.
 
THURSDAY, SEPTEMBER 5, 2013
 Officials report no issues are being worked with the Minotaur 5 rocket, the LADEE spacecraft or ground systems, and everything is on track for launch Friday night at 11:27 p.m. EDT (0327 GMT). The launch from pad 0B at the Mid-Atlantic Regional Spaceport, a facility owned and operated by the Virginia Commercial Space Flight Authority, should be visible along the U.S. East Coast from South Carolina to New England.
If you're in the area and want to see the launch, check out this map (http://spaceflightnow.com/minotaur/ladee/visibility.html) showing its visibility, weather permitting.
Technicians are today arming the Minotaur rocket's five solid-fueled stages and conducting final checks and closeouts.
The launch countdown will begin at T-minus 5 hours at 6:27 p.m. EDT (2237 GMT). The launch team will activate the Minotaur booster, check its communications links with the Wallops range systems, and put the launch vehicle through testing to verify its readiness for liftoff.
The launch window Friday night extends for 5 minutes.
The weather forecast calls for mostly clear skies and favorable conditions, with just a 5 percent chance of bad weather preventing launch.

ЦитироватьMinotaur 5 launch ground track

(https://img.novosti-kosmonavtiki.ru/28319.png)
This map illustrates the ground track that the Minotaur 5 rocket will follow during launch. Credit: Orbital Sciences Corp.

ЦитироватьMinotaur 5 launch timeline
SPACEFLIGHT NOW
Posted: August 26, 2013

T-00:00    Liftoff
The first stage's decommissioned Peacekeeper SR118 solid rocket motor ignites to begin the Minotaur 5 rocket's mission. Pitch and roll commands two seconds later will put the rocket on the proper trajectory.

T+00:38.5    Max-Q
Aerodynamic pressure on the vehicle reaches its peak as the Minotaur 5 accelerates through the lower atmosphere.

T+00:56.9    Stage 1 Sep./Stage 2 Ignition
At an altitude of 14 miles, the rocket's ATK-built solid-fueled first stage exhausts its supply of propellant and is jettisoned. The second stage's SR119 motor ignites to continue the flight toward space.

T+02:15.4    Stage 2 Sep./Stage 3 Ignition
The second stage SR119 motor, built by Aerojet Rocketdyne, burns out at an altitude of 61 miles. The Hercules SR120 third stage motor fires for a 72-second burn.

T+02:43.0    Fairing Jettison
The 92-inch graphite-epoxy aluminum honeycomb payload fairing that protected the satellites during the ride through the lower atmosphere is jettisoned as the rocket ascends into space at an altitude of 77 miles.

T+03:27.6    Stage 3 Burnout
The Hercules SR120 motor completes its burn and the Minotaur 4 enters a coast period lasting almost 4 minutes, during which the vehicle's altitude will soar to more than 160 miles in altitude.

T+07:11.6    Stage 3 Separation
The Minotaur's third stage is released to re-enter Earth's atmosphere.

T+07:22.8    Stage 4 Ignition
The Star 48BV solid rocket motor is ignited for an 85-second burn to place the Minotaur 5 rocket into a low-altitude parking orbit.

T+08:47.6    Stage 4 Burnout
The Minotaur's fourth stage motor, built by ATK, exhausts its solid propellant after reaching orbit. The launcher begins a coast phase lasting more than 8 minutes before ignition of the fifth stage motor.

T+14:26.9    Stage 4 Separation
The Star 48BV fourth stage motor is jettisoned.

T+15:41.9    Stage 5 Spin-up
The Minotaur's Star 37FM fifth stage will spin up for stabilization before ignition. The spin also provides better orbital injection accuracy.

T+16:56.9    Stage 5 Ignition
The fifth stage motor ignites for a 63-second burn.

T+18:00.4    Stage 5 Burnout
The fifth stage burns out after reaching a planned orbit with a low point of 124 miles, a high point of 172,741 miles and an inclination of 37.65 degrees.

T+21:56.9    Stage 5 De-spin
Two small yo-yo-like structures are extended and released from the Star 37FM motor to reduce the spinning motion the Minotaur rocket and LADEE are experiencing in preparation for satellite separation.

T+23:26.9    LADEE Separation
NASA's LADEE spacecraft deploys from the Minotaur fifth stage to begin its journey to the moon.

ЦитироватьMinotaur V
 
Launch Date: September 6, 2013
Launch Location: Wallops Flight Facility (WFF), Virginia
Mission Customer: U.S. Air Force Space and Missile Systems Center (SMC)

(https://img.novosti-kosmonavtiki.ru/88576.jpg)
(https://img.novosti-kosmonavtiki.ru/88577.jpg)

The inaugural mission of a Minotaur V rocket is scheduled to occur on September 6, 2013 to launch NASA's Lunar Atmosphere and Dust Environment (LADEE) into a lunar transfer orbit. The LADEE mission will be the 24th overall launch of the Minotaur family of vehicles, the fifth Minotaur launch from Wallops Flight Facility, and LADEE will be the 45th satellite launched by a Minotaur rocket.
 
 The mission also represents a number of firsts, including:
 

[/li]
• First launch of the Minotaur V configuration
  
• First five-stage vehicle flown by Orbital
  
• First Peacekeeper-based vehicle launched from Wallops Flight Facility
  
• First Lunar mission flown by Orbital
  
• First Lunar mission flown from Wallops
  

Minotaur will boost the LADEE Spacecraft into a highly elliptical orbit of 200 km x 278,000 km around the Earth. Over the next 23 days, as LADEE orbits Earth 3.5 times, the Moon's gravitational field will increase the perigee of its orbit. The spacecraft will fire its on-board thrusters to alter its trajectory to allow it to enter orbit around the Moon. The spacecraft is designed to conduct a 100 day mission to measure lunar dust and examine the lunar atmosphere from an orbit of 50 km above the surface of the Moon. The LADEE program is managed by NASA/Ames Research Center.
 Orbital conducts Minotaur launches under the U.S. Air Force's Orbital/Suborbital-3 contract, which is managed by the Space and Missile Systems Center (SMC), located at Los Angeles Air Force Base, CA. The Space Development and Test Wing, based at Kirtland Air Force Base in Albuquerque, NM, oversees Minotaur launches for SMC.
 
Mission Overview
 
(https://img.novosti-kosmonavtiki.ru/88578.jpg) (http://www.orbital.com/NewsInfo/MissionUpdates/MinotaurV/files/LADEE-Mission-Overview.pdf)
Click to download PDF (http://www.orbital.com/NewsInfo/MissionUpdates/MinotaurV/files/LADEE-Mission-Overview.pdf)
 
 About Minotaur V

 Minotaur V is a five-stage space launch vehicle based on the flight-proven Minotaur IV vehicle and adds a solid motor fifth stage to propel LADEE into its lunar transfer orbit. It leverages the experience of the Air Force's Peacekeeper program, along with the extensive flight heritage of Orbital's Minotaur I, Minotaur IV, Pegasus and Taurus space launch vehicles to produce a highly reliable launcher for U.S. government space programs. The standard space launch configuration of Minotaur V is made up of three decommissioned Peacekeeper solid fuel rocket motors that Orbital has upgraded and integrated with modern avionics and other subsystems, and solid fuel commercially-supplied STAR 48BV fourth and STAR 37FM fifth stages. The Minotaur V rocket is capable of launching payloads up to 342 kg (754 lbs) to trans-lunar injection orbit.

ЦитироватьLL пишет:
21:05:00 мск.

ЦитироватьVirginia launch site ready to host historic moon shot
BY STEPHEN CLARK
SPACEFLIGHT NOW
Posted: September 5, 2013

A diminutive NASA satellite is wrapped inside the nose cone of a five-stage Minotaur 5 rocket on an austere launch pad on the rural Virginia coastline, ready to begin a circuitous journey to the moon on a $280 million mission to answer enduring questions about the tenuous lunar atmosphere.

(https://img.novosti-kosmonavtiki.ru/88602.jpg)
The Minotaur 5 rocket on the launch pad. Credit: Patrick Black/NASA
 
 Scientists hope the Lunar Atmosphere and Dust Environment Explorer, or LADEE, will also solve a 45-year-old mystery - a predawn glow over the lunar limb first spotted by NASA's early moon missions, then recounted in journals recorded by Apollo astronauts. And if that's not enough technology packed into the 7.7-foot-tall LADEE spacecraft, the mission will take a key step toward overhauling the way NASA communicates with its deep space missions, potentially leading to a type of interplanetary fiber optic network allowing high-definition video and mounds of data to stream back to Earth fr om rovers on Mars, manned missions visiting asteroids, and probes to other far-flung destinations.
"The LADEE mission is going to give us whole new vistas on our nearest neighbor, and I'm very excited about that," said John Grunsfeld, associate administrator for NASA's science mission directorate.
Scheduled to blast off at 11:27 p.m. EDT Friday (0327 GMT Saturday), the bullet-shaped LADEE spacecraft will soar to space at the tip of a Minotaur 5 rocket. The 80-foot-tall rocket is sitting on launch pad 0B at the Mid-Atlantic Regional Spaceport, a complex leased and operated by the Virginia Commercial Space Flight Authority at NASA's Wallops Flight Facility.

Спойлер

The Minotaur 5 is an extended version of the smaller Minotaur 4 booster, and while all the components of the five-stage rocket have been tested in flight, they have never flown together in this configuration.
Powered by decommissioned motors fr om the U.S. Air Force's Peacekeeper ballistic missile program, the Minotaur 5 will rapidly depart the Virginia launch site, illuminating surrounding marshlands as it races east over the Atlantic Ocean.
The fiery nighttime launch should be visible along the U.S. East Coast from New England to South Carolina, and to observers as far inland as Pittsburgh.

(https://img.novosti-kosmonavtiki.ru/88603.jpg)
The Minotaur 5 rocket on the launch pad. Credit: Patrick Black/NASA
 
 Climbing and accelerating over the Atlantic, the Minotaur will fire each of its five solid-fueled motors before releasing the 844-pound LADEE spacecraft over Africa about 23 minutes after liftoff. The Minotaur 5 will deploy LADEE in a lofty elliptical orbit carrying the small satellite as far as 172,000 miles from Earth. After controllers activate LADEE and check its health, LADEE's liquid-fueled propulsion system, procured commercially from Space Systems/Loral, will fire up to three times to raise the craft's orbit high enough to be grasped by the moon's gravity.
"[The moon] swings by, whips us around behind it, and then once we come out from behind the moon, we do a big braking burn with our main engine," said Butler Hine, LADEE project manager at NASA's Ames Research Center in California, which led the mission's design and development.
If LADEE launches on time, the craft should enter lunar orbit in the first week of October. The exact timing of LADEE's maneuvers to reach the moon will hinge on the performance of the Minotaur 5 rocket. Slight deviations in the orbit achieved by the Minotaur rocket could slide LADEE's lunar arrival earlier or later, Hine said.

Communications by laser beam
LADEE will initially slip into a unique equatorial orbit about 156 miles above the moon, wh ere the satellite will switch on its laser communications package to begin a 30-day test campaign with a network of ground terminals in New Mexico, California and the Canary Islands.
The laser communications demonstration is a secondary objective for the LADEE mission, but its importance is not lost on top NASA officials.
"I'm a huge fan of laser communications and one of the reasons is that as you go farther out into the solar system, it's a much more efficient way to get high bandwidth communications at low power," Grunsfeld said.
The Lunar Laser Communications Demonstration will try to transmit data through a four-inch laser beam fired from terminal mounted on the body of the LADEE spacecraft. When the beam reaches Earth, it will paint an area more than 3 miles across.

(https://img.novosti-kosmonavtiki.ru/88604.jpg)
The LADEE spacecraft before enclosure inside the Minotaur 5's 12.8-foot diameter payload fairing. Credit: NASA Wallops/Terry Zaperach

 Laser communications have tighter pointing requirements than traditional radio systems, but a futuristic laser linkup needs less power and less mass than conventional radios, according to Don Cornwell, manager of LADEE's laser payload at Goddard. And the laser communications system on LADEE should transfer at a rate six times higher than radios, Cornwell said.
Officials project the laser system will beam 622 megabits per second of data from LADEE to Earth, and the uplink to LADEE will facilitate a bandwidth 20 megabits per second.
LADEE will not actually transmit any valuable science data during the 30-day test, but future missions could rely on similar technology to broadcast high-definition video, 3D imagery and other data-intensive products.
"Laser communications get more attractive compared to radio as you go farther in the solar system," Cornwell said. "We hope to use these systems from Mars one day."

On the trail of lunar dust
At the same time as the laser communications demonstration, LADEE's control team will commission the craft's science payload. Three science instruments are aboard LADEE:

[/li]
• The ultraviolet and visible light spectrometer, led by NASA's Ames Research Center, will remotely sense any dust, including hydrated material like water and the compound hydroxyl, lofted above the moon's surface and determine the composition of the lunar atmosphere.
  
• The neutral mass spectrometer will measure chemical abundances in the lunar atmosphere and allow scientists to study the processes driving the tenuous atmosphere. The neutral mass spectrometer is led by NASA's Goddard Space Flight Center in Maryland.
  
• The lunar dust experiment will collect impacts of dust particles to analyze their size and composition. The payload is led by the University of Colorado at Boulder.
  

Then comes LADEE's 100-day science mission, in which the small orbiter's instruments will scoop up dust particles, identify the chemical make-up of the moon's atmosphere, and look for signs of hydrated compounds, such as water and hydroxyl (OH), migrating from the moon's middle latitudes toward polar cold traps in permanent shadow, wh ere scientists say ice can sit undisturbed for billions of years.
"LADEE has two main science goals: To understand the lunar atmosphere as well as the dust environment around the moon," said Sarah Noble, LADEE's program scientist.

(https://img.novosti-kosmonavtiki.ru/88605.jpg)
Artist's concept of the LADEE spacecraft at the moon. Credit: NASA
 
 After lowering its orbit for the science phase of its mission, LADEE will dip as close as 12 miles to the moon, skimming mountaintops and sampling material just above the lunar surface. The moon's atmosphere is not what you may envision, Noble said. Its atoms never collide, technically making the lunar atmosphere an exosphere.
To get even more specific, the moon has what is called a surface boundary exosphere, a type of nearly airless atmosphere in which the exosphere extends to a body's surface and interacts directly with soil and dust. The moon, Mercury, the moons of other planets, and even large asteroids harbor surface boundary exospheres, making it the most common type of atmosphere in the solar system, Noble said.
Previous research shows an isotope of argon called argon-40 is pushed high above the moon's surface when excited by the heat of a lunar sunrise. Scientists also think the solar wind and impacts by asteroids and comets drive material off the surface to form part of the atmosphere.
"The lunar atmosphere has hundreds of different components and very unique dynamics," said Greg Delroy, LADEE's deputy project scientist at Ames.
Then there is the question of the dust believed to be responsible for the horizon flow witnessed by the Apollo astronauts.
Is levitating dust really the cause of the glow, and how does it get suspended tens of miles above the moon? LADEE will try to find out.
Delroy said meteor bombardment may be responsible for the presence of dust so far above the surface. The LADEE science team has asked amateur astronomers to monitor the moon for impacts, which could help researchers determine whether a strike causes any change in LADEE's dust readings.
Some type of so-far undetected static charge on the moon could also be the culprit in the mystery of the moon dust.
"There might be a static charge on the moon, and that area could change as different regions of the moon rotate in and out of sunlight," Delroy said. "That could cause an electrostatic force to act on dust."
Noble said now is a good time to launch LADEE because the lunar atmosphere is so delicate it could be disturbed or altered, at least temporarily, by the spacecraft landings kicking up dust. It has been 40 years since the last Apollo landing, and several companies and countries are planning unmanned moon landings in the coming years.
Scientists hope LADEE's results will shed light on mysterious atmospheres around other worlds in the solar system, such as Mercury. The advantage of studying the moon is scientists already have lunar samples and know the moon's composition.
"The moon is an excellent place to start," Delroy said.

[свернуть]

ЦитироватьМОСКВА, 7 сен — РИА Новости. Ракета "Минотавр-5", стартовавшая в субботу с космодрома на острове Уоллопс, на восточном побережье США, успешно вывела лунный зонд LADEE на околоземную орбиту. Трансляция запуска идет на сайте НАСА.

Через 23 минуты после запуска, который произошел, как планировалось в 07.27 мск, аппарат отделился от пятой ступени ракеты и отправился в самостоятельный полет.

Это был первый полет новой ракеты "Минотавр-5" (Minotaur V), созданной корпорацией Orbital, а также первый запуск аппарата за пределы околоземной орбиты с космодрома на острове Уоллопс.
Аппарат будет оставаться на высокоэллиптической околоземной орбите около 23 дней, чтобы выйти к Луне в нужное время и в нужном положении. В этот период ученые проведут первые проверки бортового оборудования и научных приборов.

Затем в течение недели специалисты переведут зонд на высокую окололунную орбиту, которая затем будет постепенно понижаться до рабочей орбиты высотой около 50 километров.

Главная задача аппарата LADEE (Lunar Atmosphere and Dust Environment Explorer) — исследование крайне разреженной лунной атмосферы (экзосферы) и пылевых частиц у ее поверхности. Собранные данные помогут ученым судить о экзосфере Меркурия и других тел Солнечной системы.

С помощью этого аппарата будет также проведен эксперимент по лазерной связи между Луной и Землей.

Цитировать@RT_russian
Запуск космического аппарата NASA - LADEE - был виден невооружённым глазом в небе над Нью-Йорком (ФОТО) pic.twitter.com/BLCLIbgCtT

ЦитироватьNASA's LADEE spacecraft remained in safe mode following its flawless launch on Saturday when it encountered a minor problem with its reaction wheels that are used to control the vehicle's orientation in space.

LADEE was launched atop a Minotaur V rocket that blasted off fr om Pad 0B at Wallops Flight Facility at 3:27 UTC on Saturday, 11:26 p.m. local time on Friday. Ascent and orbital insertion was completely successful and LADEE was delivered to its expected Lunar Transfer Orbit by the Minotaur rocket that performed a 24-minute ascent mission. LADEE's Countdown and Launch is detailed in the mission update below.

Following separation from the launch vehicle, the LADEE spacecraft established communications with the Hartebeesthoek ground station, South Africa that relayed telemetry to the LADEE Mission Operations Center at NASA's Ames Research Center, California. Telemetry indicated that there were no problems with the spacecraft as it went through its initial steps in orbit. LADEE entered an automatic safe mode after orbital insertion and was expected to transition to nominal operations within 24 hours after launch.

One of the next steps was the acquisition of three-axis control. For that, LADEE had two options – using its four Attitude Control Thrusters or using the Reaction Wheels of the vehicle. In the event of larger rates on the vehicle as a result of spacecraft separation, the thrusters were to be used, but LADEE only showed small rates so that the reaction wheels were activated to correct the small attitude bias.

Shortly after activation, the reaction wheels were disabled again after a current lim it was exceeded by the wheels that drew more current than expected for some reason. The flight computer automatically turned the system off to wait for input from Earth while keeping the spacecraft in safe mode. Data of the anomaly is already being studied by Mission Controllers.

The Reaction Wheels are the primary attitude control system for the LADEE mission. The four Reaction Wheels are arranged in a pyramidal fashion to provide three-axis stabilization. They are used for precise vehicle pointing as well as slew maneuvers. During Reaction Wheel momentum dumps, the RCS thrusters are used to counteract forces and so keep the vehicle stable.

The issue that occurred is not expected to be of a serious nature and teams expect that it will be resolved for the mission to continue without being impacted by the anomaly. Acquiring three-axis control is not a critical requirement for LADEE, because it features body-mounted solar panels that can generate power in virtually any spacecraft orientation. Spacecraft with fixed solar panels have to be in a sun-pointing attitude to produce power.

Additionally, LADEE could use its Attitude Control Thrusters to maintain its attitude should the Reaction Wheels not be available any time soon. Using the thrusters would consume valuable propellant that is needed for orbit maintenance once reaching the Moon. Good attitude control will be required during the first Trajectory Maneuver planned at L+6 Days.

Mission Controllers will continue to troubleshoot the anomaly and send commands to the spacecraft once a solution is found.

ЦитироватьBut there's no reason to panic, NASA officials said.

"This is not an unusual event in spacecraft," Pete Worden, director of NASA's Ames Research Center in Moffett Field, Calif., which is leading the LADEE mission, said during a press conference in the wee hours of Saturday morning (Sept. 7). LADEE was developed and built at the Ames center.

"I've been involved with a lot of missions, particularly missions with small spacecraft," Worden said. "[They] quite often have things that don't come on the way you want. The really important thing is that we have full communications. Everything is healthy onboard the spacecraft. Everything is working, and the computer did what it was supposed to do."

Цитироватьche wi пишет:
з.ы. поправьте, если ошибаюсь: reaction wheels (которые отключил бортовой компьютер LADEE) – это подобного рода  двигатели-маховики (http://www.vniiem.ru/ru/index.php?view=article&id=288:2010-02-17-21-42-21)  для ориентации КА?

Цитироватьinstml пишет:
 LADEE Status

Sept. 7, 1:40 p.m. EDT Update

NASA has confirmed that the reaction wheels of its Lunar Atmosphere and Dust Environment Explorer (LADEE) were successfully brought back on-line and the spacecraft has acquired its safe-mode attitude profile.
...

 http://www.nasa.gov/mission_pages/ladee/main/index.html

ЦитироватьМОСКВА, 12 сен — РИА Новости. Любители космонавтики заметили на одной из фотографий запуска американского лунного зонда LADEE утром 7 сентября маленькую лягушку, которая при старте ракеты тоже взлетела в воздух, фотография опубликована американским космическим агентством НАСА.

Ракета "Минотавр-5" (Minotaur V) с лунным зондом успешно стартовала в 07.27 мск субботы со Среднеатлантического регионального космопорта (MARS) на острове Уоллопс, штат Виргиния. Это был первый полет новой ракеты, созданной корпорацией Orbital, а также первый запуск аппарата за пределы околоземной орбиты с космодрома на острове Уоллопс.

На одном из снимков старта рядом с ракетой, которая уже оторвалась от земли, на фоне дыма от двигателей видна маленькая лягушка, которая тоже как бы "взлетает". Официальный представитель космодрома Джереми Эггерс подтвердил интернет-изданию Universe Today, что фотография подлинная и не подвергалась какой-либо обработке.

Как отмечает Universe Today, "дальнейшая судьба лягушки неизвестна".

Другая знаменитая "встреча" животного и космического корабля произошла в 2005 году, когда гриф-индейка, распространенная в штате Флорида птица, врезалась в топливный бак шаттла "Дискавери". Кроме того, совсем недавно в ходе тестовых испытаний инновационная ракета Grasshopper, которую разрабатывает компания SpaceX, сильно напугала стадо коров, которое в полном составе пробежало перед одной из камер, снимавших испытания.

ЦитироватьСтарый пишет:
Ради справедливости и приоритета надо отметить что первую в мире фотографию лягушки пострадавшей при космическом запуске опубликовал на этом форуме Вован. Лягушка зажарилась при пуске Зенита.

ЦитироватьЛуноход пишет:

ЦитироватьСтарый пишет:
Ради справедливости и приоритета надо отметить что первую в мире фотографию лягушки пострадавшей при космическом запуске опубликовал на этом форуме Вован. Лягушка зажарилась при пуске Зенита.

А где можно глянуть?

ЦитироватьЛуноход пишет:
Помнится, у них ещё летучая мышь на Шаттле улетела.

ЦитироватьAfter overcoming initial trouble early in its Mission, NASA's LADEE spacecraft has completed its first major Perigee Maneuver on Friday - climbing up in its Lunar Transfer Orbit around Earth, on track for its arrival at the Moon on October 6.

Спойлер

Following its spectacular launch last Saturday (UTC), LADEE was delivered to its planned orbit with an apogee of about 260,000 Kilometers and a period of 6.4 days. After starting initial orbital operations, LADEE ran into trouble with its reaction wheels that drew more power than expected, resulting in an unplanned safe mode which was successfully resolved shortly thereafter. The reaction wheels were in proper condition and the fault protection limit that caused the system to be disabled was inhibited for the re-start.

The initial checkout of the vehicle was successfully completed by September 10 and showed that LADEE was in good condition as it passed apogee and began its trip down to perigee.

On the 11th, LADEE entered safe mode again due to an alignment error between the two star tracker camera heads, affecting the rate estimator when the sun occludes one of the cameras. Mission Controllers at NASA's Ames Research Center studied the situation and corrected the error later that day to resume nominal mission operations.

Later on Wednesday, the spacecraft performed its AM-1b maneuver – a short test of its Orbital Control System (OCS) thruster. The burn took place at 23:00 UTC and provided a change in velocity of 9.34 meters per second. The engine was burned 90 degrees out of plane to adjust the right ascension of the ascending node and move the Lunar Orbit Insertion Maneuver back by 30 minutes to avoid a gap in Deep Space Network Coverage on October 6.

With the engine checked out, LADEE was ready for its next maneuver – the first major engine burn of the mission taking place at perigee, the low point of its elliptical orbit around Earth. The OCS thruster was ignited at 16:38 UTC on a 17m/s burn to boost the apogee of the orbit.

Initial indications are that the burn was performed successfully, placing LADEE in a 7.6-day orbit ahead of the next Perigee Maneuver, planned for September 21 to increase the orbital period to 10 days for the final orbit around Earth that will set the vehicle up for a small Trajectory Correction Maneuver when passing perigee on October 1.

At that point, LADEE enters a Lunar-Transfer Trajectory that will take it to the moon in 5.3 days, setting the stage for the first of three Lunar Orbit Insertion Maneuvers.

While LADEE completes its second orbit around Earth, in-depth spacecraft testing is underway.

[свернуть]

Цитироватьpkl пишет:
Живодёры

Цитироватьche wi пишет:
 НАСА: лунный зонд LADEE случайно "забрал" с собой в космос лягушку
 http://ria.ru/science/20130912/962736146.html

ЦитироватьНа одном из снимков старта рядом с ракетой, которая уже оторвалась от земли, на фоне дыма от двигателей видна маленькая лягушка, которая тоже как бы "взлетает". Официальный представитель космодрома Джереми Эггерс подтвердил интернет-изданию Universe Today, что фотография подлинная и не подвергалась какой-либо обработке.

Как отмечает Universe Today, "дальнейшая судьба лягушки неизвестна".

:)  фото здесь (http://www.universetoday.com/104679/absolutely-incredible-photo-frog-launches-with-ladee/)

ЦитироватьNASA's LADEE Spacecraft has completed its second Perigee Maneuver on Saturday as it made its second close approach to Earth. This second Perigee Maneuver marked the final major engine burn ahead of the first Lunar Orbit Insertion Maneuver planned for October 6, 2013.

Спойлер

The first Perigee Maneuver performed on September 13 after one orbit around Earth put LADEE into an orbit with a duration of 7.6 days. Over the course of its second orbit, LADEE underwent electrical checkouts of its instrument payload. While making its Phasing Loops and during Orbit Insertion, the instrument covers remain in place to avoid contamination as a result of the large engine burns.

LADEE's Neutral Mass Spectrometer (NMS) completed its aliveness and electrical check and the Ultraviolet-Visible Spectrometer (UVS) dark calibration test was also completed. Both instruments were awarded a clean bill of health after their first checks.

On September 17, the Lasercom Spacecraft Terminal (LLST) underwent electrical checkouts to make sure it was ready for operation. These initial tests did not yet involve optical transmission to or from Earth.

On September 18, the Neutral Mass Spectrometer completed its cap ejection preparation, as well as peak spectra calibration. The Ultraviolet-Visible Spectrometer performed more dark calibrations before instrument heaters were adjusted to higher temperatures to complete the instrument bake-out. NMS Argon and Helium Baseline calibration was completed on the 19th to fully prepare the instrument for cap ejection later in the mission.

[свернуть]

On Friday, the Perigee Maneuver 2 sequence was uplinked to the spacecraft  and verified to ensure the maneuver is performed as planned. The PM2 main engine burn took place at 11:53 UTC on Saturday and provided a change in velocity of 10 meters per second to increase the apogee of LADEE's Orbit to match the orbital altitude of the Moon. The orbital period was increased to roughly ten days.

Now in its third orbit, LADEE will swing around Earth one last time to pass perigee on October 1. The third perigee passage does not feature a major engine burn - an optional Trajectory Correction Maneuver may be performed at Perigee #3 should it be necessary. After passing its final perigee, LADEE will set sail for the Moon, entering a hyperbolic Trans-Lunar Trajectory as the Moon's gravity pulls the vehicle in. Another Trajectory Correction is performed 36 hours after Perigee #3.

On October 6, LADEE will conduct its first Lunar Orbit Insertion maneuver to enter an elliptical orbit around the Moon that is circularized at a lower altitude by two additional burns that take place over a period of about a week to set the stage for initial commissioning activities in Lunar Orbit.

ЦитироватьNASA's LADEE Spacecraft has bid farewell to Earth and has set sail for the Moon after making its final Perigee pass on Tuesday. LADEE is set to arrive at the Moon on October 6 and begin a series of Lunar Orbit Insertion Maneuvers ahead of Commissioning and Science Operations.

After passing perigee on September 21 and performing the second large Perigee Maneuver, LADEE was in a 10-day orbit for one last lap around the Earth before heading to the Moon. That last orbit was used for more spacecraft testing and commissioning operations.

The final instrument to be tested was the Lunar Dust Experiment that was awarded a clean bill of health after it had completed aliveness and electrical checks.

Also, the Lunar LaserCom Terminal on the vehicle completed more testing activities in preparation for its mission that will be performed during the LADEE Commissioning Phase in lunar orbit.

Tracking the LADEE spacecraft, Flight Dynamics specialists determined that the maneuver performed on the second perigee was executed very accurately - enabling the team to scrub the optional Trajectory Correction on the third perigee pass.

After passing apogee last week, LADEE was inbound again, set to coast through its third and final perigee. The spacecraft passed perigee at 11:00 UTC on Tuesday, swinging by Earth on last time. Now, the spacecraft is on a direct transfer trajectory that takes it to the Moon.

One final Trajectory Correction Maneuver is planned on Tuesday at 22:00 UTC to fine-tune the vehicle's path to the LOI-1 point. The TCM is a small 0.9-meter per second burn and targets the proper conditions for Lunar Orbit Insertion on October 6.

Спойлер

LADEE will use a total of three Lunar Orbit Insertion Burns to enter its Commissioning Orbit. The first LOI Burn is set for October 6 at 10:57:00 UTC and is a critical maneuver that will be observed live by NASA's Deep Space Network to provide mission controllers with vehicle telemetry. The burn is planned to change LADEE's velocity by 329.86 meters per second, making this the largest burn executed on this mission.

LOI-1 places LADEE in a lunar orbit with a duration of 24 hours and a periselene of 750 Kilometers. On October 7 at 22:51:32 UTC, LADEE is planned to perform a correction maneuver to adjust its orbit in case of LOI-1 insertion errors.

After three orbits of the moon in that orbit, gravitational perturbations will have lowered the periselene to about 250 Kilometers which is accounted for in LADEE's mission design. On October 9 at 10:37:55 UTC, the LOI-2 burn comes up to significantly lower the aposelene and put LADEE in a 4-hour orbit around the Moon. LOI-2 has a planned delta-v of 295.99 meters per second.

LOI-3 is set for October 12 at 10:37:35 UTC and will change the vehicle's velocity by 238.56 meters per second, putting it in its circular 250-Kilometer orbit around the Moon where it will begin in-orbit commissioning and perform the Lunar LaserCom demonstration.

Following its insertion into Lunar Orbit, LADEE starts 40 days of commissioning with 20 days reserved for contingencies. The first three days of commissioning are dedicated to spacecraft checkouts in lunar orbit followed by two days of instrument aliveness and electrical testing. Also, the deployment of covers on the LDEX, UVS and NMS instruments is performed – all three are considered mission critical requiring live telemetry downlink.

The next 25 days of commissioning are divided into 3-day intervals for High-Altitude Science Checkouts and 4-day periods of Lunar Laser Communications Demonstrations – totaling 9 days of instrument checkouts and 16 days of LLCD.

[свернуть]

———
October 1, 2013

ЦитироватьNASA's LADEE spacecraft has successfully ins erted itself into its preliminary orbit around the Moon on Sunday after completing a one-month journey - being launched atop a Minotaur V rocket on September 7 (UTC) and completing three phasing loops around Earth, LADEE entered its final trans-lunar trajectory earlier this week to set the stage for LOI-1, as the first insertion burn is known.

The maneuver was executed flawlessly on Sunday starting at 10:57 UTC by a small crew of spacecraft engineers & trajectory specialists at NASA Ames, and experts at NASA's Deep Space Network as the rest of the NASA mission team was sidelined because of the US Federal Government Shutdown.

LADEE's critical insertion burn also occurred in a complete news blackout as NASA's office of communications is also closed.

Thanks to spacecraft navigators Mike Loucks and John Carrico, Jr. over at the The Astrogator's Guild, we have been informed on the outcome of Sunday's critical maneuver.

LADEE had entered its trans-lunar trajectory on Tuesday after passing perigee the last time, flying past Earth for the final time and heading out to the Moon. On Saturday at 19:03 UTC, LADEE entered the Moon's Sphere meaning that the Moon was the primary gravitational body acting on the vehicle, starting to pull the spacecraft in.

But to ins ert itself into a lunar orbit, LADEE had to perform a critical engine burn to allow the spacecraft to be captured in a retrograde orbit around the Moon.

(https://forum.novosti-kosmonavtiki.ru/forum/file/23548) (http://www.spaceflight101.com/uploads/6/4/0/6/6406961/6613829_orig.jpg)

LADEE's trajectory was designed to have the vehicle pass its first periselene before the burn and become visible to Deep Space Network ground stations in order to provide live telemetry data.

About five minutes after making its close flyby of the Moon, LADEE ignited its main engine, a BT-4 derivative, at 10:57 UTC on Sunday on a four-minute burn. LOI-1 was one of the most critical events of the mission - without it, the spacecraft would have passed the Moon with no hope of returning.

LADEE's propulsion system showed good performance during its burn that was much longer than any previous burn executed in the mission. The LOI-1 burn had a planned change in velocity of 329.8 meters per second to place the vehicle in an elliptical lunar orbit with a duration of 24 hours.

This 24-hour orbit has a periselene (low point) of 590 Kilometers. Tracking LADEE, the mission team will determine the exact orbital parameters to begin planning subsequent maneuvers that will be taking place over the course of the next week.

LADEE will spend three days in its initial orbit, making its first three laps around the Moon. Over the course of these three days, LADEE's orbit will be lowered to a new periselene of 250 Kilometers as a result of gravitational perturbations in the Earth-Moon System. This effect is being used in LADEE's mission design.

Спойлер

Coming up on Monday at 22:51 UTC is an optional trajectory maneuver to correct any errors that have occurred on insertion. This maneuver will be planned once LADEE's initial orbital parameters are known.

The next major maneuver will be the LOI-2 burn that is planned to begin at 10:37 UTC on Wednesday. This is another major engine burn with a planned delta-v of 295.99 meters per second to place the vehicle in a four-hour orbit around the Moon. LADEE will spend three days in that orbit to allow sufficient tracking to plan the LOI-3 engine burn.

LOI-3 is se t for October 12 at 10:37 UTC and will change the vehicle's velocity by 238.56 meters per second, putting it in its circular 250-Kilometer orbit around the Moon where it will begin in-orbit commissioning and perform the Lunar LaserCom demonstration.

LADEE's science orbit has been carefully designed, taking into account the mission's scientific requirements and the Moon's uneven gravitational field that makes orbit maintenance at low altitudes very difficult, requiring a large amount of propellant for maintenance maneuvers.

That is why trajectory designers chose an elliptical science orbit with a periselene of 50 Kilometers, a variable aposelene no higher than 150 Kilometers, and an inclination of 157 degrees. Science requirements dictate that the terminator crossing (border between day and night) occurs near perigee at an altitude of less than 50 Kilometers for proper exospheric measurements.

This is required for sun occultation observations to detect atmospheric dust.

On-orbit commissioning is planned to take 30 days in the 250-Kilometer orbit, plus 10 days of checkouts in the lower science orbit of 50 Kilometers. 20 extra days can be added to the commissioning sequence should teams run into problems of any kind.

The first three days of commissioning are dedicated to spacecraft checkouts in lunar orbit followed by two days of instrument aliveness and electrical testing. Also, the deployment of covers on the LDEX, UVS and NMS instruments is performed.

The next 25 days of commissioning are divided in to 3-day intervals for High-Altitude Science Checkouts and 4-day periods of Lunar Laser Communications Demonstrations – totaling 9 days of instrument checkouts and 16 days of LLCD.

[свернуть]

http://www.youtube.com/watch?v=VPyrjwEURhw (http://www.youtube.com/watch?v=VPyrjwEURhw)

———
October 6, 2013

ЦитироватьМОСКВА, 7 окт — РИА Новости. Американская автоматическая станция LADEE успешно вышла на орбиту Луны, теперь аппарат постепенно начнет снижать высоту орбиты до высоты около 50 километров, где начнется его основная научная программа, сообщает сайт Spaceflight101.

Зонд LADEE был успешно запущен в начале сентября с космодрома на острове Уоллопс. Около трех недель он оставался на высокоэллиптической околоземной орбите, чтобы выйти к Луне в нужное время и в нужном положении. За это время ученые провели первые проверки бортового оборудования и научных приборов.

Накануне во время подлета к Луне LADEE провел торможение двигателем, был "подхвачен" гравитацией спутника Земли и вышел на окололунную орбиту с максимальной высотой 750 километров. В субботу, 12 октября, аппарат перейдет на круговую лунную орбиту высотой 250 километров. На этой орбите зонд начнет подготовку к исследовательской программе, а также проведет сеанс лазерной связи с Землей. Затем орбиту будут постепенно понижать до высоты около 50 километров.

В то же время официальной информации о ходе миссии нет, поскольку ее сайт и аккаунты в социальных сетях закрыты из-за бюджетного кризиса в США.

Проект LADEE (Lunar Atmosphere and Dust Environment Explorer) общей стоимостью 280 миллионов долларов предназначен для исследования крайне разреженной лунной атмосферы (экзосферы) и пылевых частиц у ее поверхности. Собранные данные помогут ученым судить об экзосфере Меркурия и других тел Солнечной системы. С помощью аппарата LADEE будет также проведен эксперимент по лазерной связи между Луной и Землей. Разработчики заявили, что скорость передачи данных на спутник составит до 20 мегабит в секунду, а от спутника — 622 мегабит.

ЦитироватьThe LADEE spacecraft in orbit around the Moon has executed its LOI-2 maneuver on Wednesday to lower its initial lunar orbit as part of a three-step process that started with Lunar Orbit Insertion last Sunday.

After arriving in its highly elliptical orbit around the Moon of about 590 by 15,700 Kilometers, LADEE was closely tracked by ground stations to determine its precise orbit in order to plan the LOI-2 burn to lower the aposelene. Tracking revealed that LADEE performed an accurate insertion and was in the expected orbit that it would spend three days in.

Gravitational perturbations in the Earth-Moon system acting on the small LADEE spacecraft caused its periselene to decrease in altitude which was planned in the mission's trajectory profile. After three orbits in the highly elliptical orbit, the LOI-2 burn occurred at 10:38 UTC on Wednesday, October 9.

This maneuver was a 220.8-second burn of the High Performance Apogee Thruster - a variant of the BT-4 engine that is used on a variety of spacecraft. The burn had a planned change in velocity of 293 meters per second to reduce the aposelene to 2,220 Kilometers, placing LADEE in a four-hour orbit.

(https://forum.novosti-kosmonavtiki.ru/forum/file/23658)

LADEE will again spend three days in this orbit before making its LOI-3 burn to allow tracking of the spacecraft and sufficient time to plan the next maneuver. LOI-3 will put LADEE into a circular orbit of 250 Kilometers where the spacecraft will begin its commissioning operation and start the Lunar LaserCom demonstration. The LOI-3 burn is planned to occur at 10:37 on Saturday.

———
October 9, 2013

ЦитироватьLL пишет:
Что-то ничего не слышно о LADEE, что с ней (с ним-аппаратом)?

ЦитироватьThe LADEE Spacecraft has reached its Commissioning Orbit around the Moon after successfully completing Lunar Orbit Insertion Maneuver 3 on Sunday. LADEE fired its main engine at 3:33 UTC on Sunday to lower its orbit around the Moon to start spacecraft commissioning.

Spacecraft navigators Mike Loucks and John Carrico, Jr earlier explained that perturbations in the Earth-Moon System caused the periselene of the orbit to get lower than expected. The cause of this was a very slight (1%) underperformance on LOI-1 that ins erted LADEE into an orbit with a slightly higher aposelene, causing the spacecraft to encounter more Earth perturbations than expected.

LADEE periselene ended up at 235 Kilometers instead of the planned 250 Kilometers which did not present a problem since LADEE is targeting a lower science orbit. The orbit prior to LOI-3 was about 235 by 2,213 Kilometers and the LOI-3 burn was planned to put LADEE into a 235 by 250-Kilometer orbit.

LADEE's propulsion system performed nominally – marking the successful conclusion of the Lunar Orbit Insertion Phase. Tracking will confirm the exact orbital parameters.

LADEE is now in its Commissioning Orbit where it will spend 30 days. Over the first three days of commissioning, LADEE performs spacecraft checkouts in lunar orbit followed by two days of instrument aliveness and electrical testing. Also, the deployment of covers on the LDEX, UVS and NMS instruments is performed – all three are considered mission critical requiring live telemetry downlink.

The next 25 days of commissioning are dedicated to 3-day intervals of High-Altitude Science Checkouts and 4-day periods of Lunar Laser Communications Demonstrations – totaling 9 days of instrument checkouts and 16 days of LLCD. During commissioning, LADEE can use LLCD for about 13 to 15 minutes per orbit when a ground station is in view. During LLCD ops, LADEE has to point at Earth with an error of less than one degree to enable the fine-pointing to be accomplished by the payload itself.

After 30 days of LADEE commissioning, its orbit will have drifted to a more elliptical trajectory as the Moon's lumpy gravitational field causes the periselene to drop and aposelene to increase.

At that point, the aposelene is lowered to match the periselene altitude, placing LADEE in a circular orbit and set up the proper location of the periselene passage near the terminator.

Shortly after the circularization maneuver, the periselene is reduced to target the terminator. The orbit is se t up in a way so that the periselene drops to 50 Kilometers after ten days to enable the start of science operations. Over the course of these ten days, LADEE low-altitude instrument checkouts are performed around periselene which also provides initial science data. 40 days after the start of commissioning, LADEE conducts another engine burn to reduce the aposelene altitude from 260 Kilometers to 50 Kilometers to mark the beginning of science operations.

———
October 13, 2013

ЦитироватьLunar orbiter set for long-distance laser data linkup
BY STEPHEN CLARK
SPACEFLIGHT NOW
Posted: October 13, 2013
 
 NASA's LADEE spacecraft finished a week-long series of maneuvers to reach an initial operating orbit around the moon Saturday, kicking off a month of commissioning and calibrations while demonstrating a laser communications system that could lead to breakthroughs for future expeditions into deep space.

 (https://img.novosti-kosmonavtiki.ru/89482.jpg)
Artist's concept of LADEE orbiting the moon at sunrise. Credit: NASA
 
 Three burns of the probe's main engine over the last week first allowed the moon's gravity to capture LADEE in a high-altitude parking orbit, then lowered the craft's altitude into the first of two operational orbits.
Since LADEE entered lunar orbit Oct. 6, ground controllers at NASA's Ames Research Center in California lowered the spacecraft's altitude in two successive rocket firings. A burn late Saturday put LADEE into a near-circular orbit over the moon's equator at an altitude of approximately 250 kilometers, or 155 miles, mission officials said.
The Lunar Atmosphere and Dust Experiment Explorer will stay in its current orbit for 30 days, allowing engineers to check out the spacecraft's systems, perform an aliveness test on its three science instruments, deploy sensor aperture covers, and begin commissioning activities for the mission's science phase.
The $280 million mission's main purpose is to study the moon's tenuous exosphere, a type of atmosphere so thin that its atoms never collide with each other. Scientists say atmospheres like the moon's are common throughout the solar system on planets like Mercury and among the largest asteroids.
Launched from Wallops Island, Va., on Sept. 6 aboard a Minotaur 5 rocket, LADEE also carries a technology payload to test out a next-generation communications device using laser light to transmit data over long distances at higher speeds than possible with conventional radio systems.
Around Nov. 11, controllers will lower LADEE's altitude to less than 30 miles above the lunar surface to begin a 100-day science mission before the orbiter runs out of propellant and crashes into the moon in early 2014.
The Lunar Laser Communications Demonstration aboard LADEE will begin its experiments Oct. 17, linking up with ground stations in New Mexico, California and the Canary Islands and exchanging data packets at speeds unattainable with radio communications systems.

 (https://img.novosti-kosmonavtiki.ru/89483.jpg)
File photo of an optical laser experiment aimed at the moon. Credit: ESA
 
 An infrared laser beam emitted from one of the ground stations will scan the sky around the moon until it intercepts the receiver on LADEE, which will return the signal and acquire a lock. Optical communications systems like LADEE's laser instrument require more precise pointing to obtain a lock than radio transmitters.
"Once the two systems are locked and acquired, then we can send tens of megabits of data per second from the Earth up to the moon, and similarly we can send hundreds of megabits per second from the moon on LADEE down to the Earth," said Don Cornwell, the laser communication demonstration mission manager from NASA's Goddard Space Flight Center in Greenbelt, Md.
NASA says LADEE's laser demo will achieve a downlink speed from the moon to Earth of 622 megabits per second and an uplink speed of about 20 megabits per second.
Built by MIT Lincoln Laboratory, the communications payload will help build confidence for future missions to use laser data links from deep space, including NASA's manned asteroid mission and future rovers on the surface of Mars.
"NASA has a need for faster download speeds for data from space," Cornwell said. "We'd like to be able to send high-resolution images, movies in 3D even, from satellites that not only orbit the Earth but also from probes that will go to the moon and beyond."
"If you're beaming data back over a standard radio link and compare that to what we can do with a laser system, it's about like comparing a modem to fiber optics in terms of your Internet speed," said Greg Delory, LADEE's deputy project scientist at NASA's Ames Research Center. "With a typical radio link, you're talking about tens of kilobits per second on average. With the laser communications system [on LADEE], we're going to get 600 megabits per second equivalent data speed, which is just blindingly fast."

(https://img.novosti-kosmonavtiki.ru/89484.jpg)
Artist's concept of the Lunar Laser Communications Demonstration mission on LADEE. Credit: NASA
 
 Another benefit of laser communications is it requires fewer components and smaller terminals, both on the ground and in space.
"Light waves are shorter in wavelength than radio waves, so we can use smaller transmitters and receivers," Cornwell said.
NASA is also developing a laser terminal to fly as a hosted payload on a commercial communications satellite in geostationary orbit in 2017. The geostationary demonstration mission will test the laser system's ability to relay data from orbiting satellites, such as the International Space Station, to the ground at faster speeds.
"I'm a huge fan of laser communications, and one of the reasons is that as you go farther out into the solar system, it's a much more efficient way to get high bandwidth at low power," said John Grunsfeld, associate administrator of NASA's science mission directorate.
NASA is considering placing a laser communications system on its next Mars rover set for launch in 2020.
"It could be as soon as our Mars 2020 mission," Grunsfeld said. "We've already been having discussions about could you do laser communications on a rover on the surface of Mars."

ЦитироватьНынешний НАСА-эксперимент — первая двусторонняя система космической связи. А это значит, что она явно не самая совершенная — по сути, делает первые шаги. И всё же ведомство сообщает, что ей удалось безошибочно передать с Земли на лунную орбиту, где находится аппарат, данные со скоростью 20 Мбит/с. И хотя это может показаться вам слезами, в действительности потребность в передаче информации с наземных станций на КА редко бывает слишком уж большой, благо всё же основная задача таких устройств — отправка данных на Землю.

 А вот спутник с окололунной орбиты смог отправить информацию наземным наблюдателям со скоростью 622 Мбит/с (рискнём предположить, что это лучше, чем «домашний Интернет» многих из вас). Для аппарата с мощностью бортового питания 295 Вт, да ещё и передающего на 382 тыс. км, это Результат. Словом, и по скорости отправки, и по получению информации перед нами рекорд скорости связи на такое расстояние.

Цитировать"We acquired the first signals from LADEE on 26 October, and since then, we've had a series of optical uplinks and downlinks providing extremely fast laser communications," says Zoran Sodnik, ESA's project manager for the laser effort.
"We've already received data at up to 40 Mbit/s – several times faster than a typical home broadband connection."

ЦитироватьТайна лунной пыли
 ("New Yorker (http://inosmi.ru/newyorker_com/)", США (http://inosmi.ru/magazines/country_usa/))
Кейт Грин (KATE GREENE)  (http://inosmi.ru/authors//)

08/11/2013
Когда Нил Армстронг (Neil Armstrong) и Базз Олдрин (Buzz Aldrin) вернулись с Луны, в багаже у них было более 20 килограммов лунной почвы и камней, которые были упакованы в алюминиевый контейнер с уплотнителями. Благодаря им внутри поддерживалось низкое давление — как на лунной поверхности. Но когда контейнер попал к ученым в космический центр Хьюстона, они обнаружили, что эти уплотнения разрушила лунная пыль.

Лунная пыль — мелкая, как порошок, но она режет не хуже стекла. Пыль эта образуется при падении метеоритов на лунную поверхность. Они раскаляют и размельчают скальные породы и почву, которые содержат кварц и железо. А поскольку на Луне нет ветра и воды, чтобы закруглить режущие края, крошечные крупинки очень острые и имеют зазубрины. И они прилипают почти ко всему.

«Агрессивная природа лунной пыли представляет собой более серьезную проблему для инженеров и для здоровья поселенцев, чем радиация», — написал в 2006 году в своей книге «Возвращение на Луну» (Return to the Moon) астронавт из экипажа «Аполлона-17» Гаррисон «Джек» Шмитт (Harrison (Jack) Schmitt). Эта пыль пачкала скафандры и слоями снимала подошвы лунных ботинок. За шесть полетов «Аполлонов» низкое давление не удалось сохранить ни в одном контейнере с лунной породой. Пыль проникала вслед за астронавтами и внутрь космических кораблей. По словам Шмитта, она пахла порохом, и из-за нее было трудно дышать. Никто точно не знает, какое воздействие эти микроскопические частицы оказывают на легкие человека.

Пыль не просто покрывает поверхность Луны, она поднимается почти на стокилометровую высоту над ней, составляя часть ее экзосферы, где частицы привязаны к Луне силой притяжения, но расположены настолько редко, что почти никогда не сталкиваются. В 1960-е годы зонды Surveyor сняли сверкающее облако, которое во время восхода солнца плыло прямо над лунной поверхностью. Позднее астронавт «Аполлона-17» Джин Сернан (Gene Cernan), облетая Луну, зафиксировал аналогичное явление в области резкой линии, где лунный день встречается с ночью, назвав его «Терминатор». Сернан сделал несколько зарисовок, показав, как меняется пылевой ландшафт. Сначала потоки пыли поднимались с поверхности и зависали, а потом образовавшееся облако стало видно отчетливее, когда космический корабль приблизился к зоне дневного света. А поскольку ветра для формирования облака не было, его происхождение осталось загадкой. Есть предположение, что такие облака состоят из пыли, но никто не понимает, как они формируются и почему.

Возможно, на линии дня и ночи образуется электрическое поле, когда солнечный свет встречается с тенью. Оно вполне может поднять частицы пыли вверх. Физик из Колорадского университета в Боулдере Михали Хораньи (Mihály Horányi) продемонстрировал, что лунная пыль действительно может реагировать на такие электрические поля. Однако у него есть подозрения, что этот механизм недостаточно мощен, чтобы удерживать таинственные сверкающие облака в пространстве.

Данные новой космической миссии способны помочь ученым в поиске более достоверного объяснения. Прошли десятилетия с тех пор, как американские астронавты и луноходы исследовали Луну, но лунная пыль сегодня снова вызывает интерес, поскольку уже объявлено о подготовке к пилотируемым и беспилотным полетам на Луну в рамках сразу нескольких международных и коммерческих космических программ. В сентябре НАСА запустила маленький зонд LADEE (исследовательский корабль лунной атмосферы и пылевой среды), который на протяжении нескольких месяцев будет анализировать пыль и молекулы, окружающие единственный естественный спутник Земли.

Этот зонд размером с небольшой автомобиль, и он заключен в оболочку из солнечных панелей. В носовой части корабля имеется четыре квадратных прибора. Это пылемер, частично сконструированный Хораньи, и два химических анализатора для идентификации молекул таких веществ, как гелий и натрий. На боку зонда установлено коммуникационное устройство, передающее на Землю при помощи лазерного пучка данные, например, о количестве больших и малых частиц, об их местоположении и так далее. Недавно это устройство установило рекорд по скорости связи между НАСА и Луной, передав данные на расстояние почти 400 тысяч километров со скоростью 622 мегабита в секунду. Это примерно в 70 раз превышает скорость среднего широкополосного соединения в США.

Время для этого полета стоимостью 280 миллионов долларов выбрано весьма удачно, потому что приборы LADEE получают почти ничем не искаженную картину плотности пыли и химического состава Луны, опережая всех остальных. Китай, Индия, Япония и Россия объявили, что планируют отправить свои зонды и луноходы в предстоящие годы. Премия Google Lunar X PRIZE дает инженерам неплохой стимул для создания автоматического лунохода с камерами, который должен прилуниться и начать передавать картинку с лунной поверхности на Землю к 2015 году. Начинающая космическая компания Golden Spikе намерена в следующем десятилетии приступить к пилотируемым полетам.

Когда миссия LADEE через несколько месяцев будет завершена, зонд станет составной частью того объема космического материала в 15 тонн, который ежедневно падает на Луну. Он создаст свое собственное облако лунной пыли, передавая на Землю последние данные.

Оригинал публикации: THE MYSTERY OF MOON DUST (http://www.newyorker.com/online/blogs/elements/2013/11/the-mystery-of-moon-dust.html)
Опубликовано: 06/11/2013 12:52

ЦитироватьSalo пишет:
зафиксировал аналогичное явление в области резкой линии, где лунный день встречается с ночью, назвав его «Терминатор». и т.д.

ЦитироватьNASA's LADEE Spacecraft has begun its science mission in Lunar Orbit, exploring the Moon's thin exosphere and dust environment to answer long standing questions on the formation and evolution of exospheres which will also help understand other, more distant planetary bodies with exospheres.

Using a suite of three instruments, LADEE studies the density, composition and spatial as well as temporal variability of the lunar exosphere to probe its origin and study its response to phenomena like solar wind.

The mission also attempts to examine the abundance and variability of dust particles that may be present in the exosphere. Scientists want to study the lunar atmosphere in an undisturbed condition before any significant human or robotic activity disturbs the fragile exosphere.

"A thorough understanding of the characteristics of our lunar neighbor will help researchers understand other small bodies in the solar system, such as asteroids, Mercury, and the moons of outer planets," said Sarah Noble, LADEE program scientist at NASA Headquarters.

On November 20, LADEE adjusted its orbit in order to achieve the low science orbit of the mission with a periselene at less than 50 Kilometers and the aposelene being managed at 50 to 100 Kilometers. The LADEE mission requires the spacecraft to be in an equatorial orbit with the periselene carefully positioned near the terminator crossing (border between day and night) for sun occultation observations to detect atmospheric dust.

With LADEE now ins erted in to its target orbit, trajectory planners start a constant fight against the Moon's lumpy gravitational field that causes an unsteady drift of the entire orbit as the periselene altitude drops and the aposelene altitude increases. This requires LADEE to perform orbit maintenance maneuvers every couple of days in order to keep its periselene attitude stable and constantly re-target the terminator crossing to ensure good positioning for science data acquisition.

"LADEE will perform regular orbital maintenance maneuvers to keep the spacecraft's altitude within a safe range above the surface that maximizes the science return," said Butler Hine, LADEE project manager.

Orbit maintenance maneuvers occur every three two five days, but can also be as infrequent as once every two weeks depending on lunar cycle and gravitational properties. This can not be predicted long-term and requires trajectory planners to adjust maneuver plans constantly and on short notice.

LADEE's primary science mission is 100 days in duration. Extensions are possible depending on the fuel consumption during these 100 days as LADEE's propellant supply is by far the limiting factor of the mission. The spacecraft will be kept in orbit as long as the propellant will last. As a possible extended mission, scientists desire to allow LADEE to drop into a lower orbit to capture the most valuable data – studying exosphere properties at low altitude levels.

LADEE science operations are planned in a per-orbit fashion. With LADEE in an orbit with a period of 113 minutes, mission planners will be planning 12 orbits per day and a single day with an additional 'leap orbit' every few days. A variety of orbit types has been specified characterized by major vehicle operations or attitude activities.

Orbits can include two types of NMS orbits during which the Neutral Mass Spectrometer is operated in continuous mode while the LADEE vehicle makes a 360-degree rotation per orbit to keep the instrument pointed at its target (ram side or 30° down). The second NMS mode is rotisserie mode during which LADEE rotates at 1RPM. The first NMS mode is compatible with LDEX, Dust Detector Operations.

Two additional orbit types operate the Ultraviolet-Visible Spectrometer. In its first mode, UVS is operated continuously, making limb observations in stare and nod modes. (See instrument page for details) In the second mode, the solar viewer is operated for occultation measurements. LDEX, the dust-measuring instrument, is compatible with both UVS orbit types.

The remaining two orbit types are housekeeping orbits – one being a power orbit during which no instruments are active to allow LADEE to recharge its battery. The other type is a communications orbit during which the vehicle is pointed to Earth and downlinks science data via its Medium Gain Antenna. At least two Comm Orbits are performed per day. Command uplink can take place outside of the regular communication slots, but mission operations aim to perform the daily uplink during these sessions.

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Spaceflight101 | November 22, 2013

ЦитироватьNow in orbit around the moon, NASA's newest lunar mission has completed the commissioning phase, and its science instruments have passed their preliminary checks.

The Lunar Atmosphere and Dust Environment Explorer (LADEE), launched Sept. 6, 2013, carries three science instruments designed to gather detailed information about the structure and composition of the thin lunar atmosphere and determine whether dust is being lofted into the lunar sky.

A thorough understanding of these characteristics of our nearest celestial neighbor will help researchers understand other bodies in the solar system, such as large asteroids, Mercury, and the moons of outer planets.

"This is very promising for LADEE's science phase - we are already seeing the shape of things to come," said Rick Elphic, LADEE project scientist at NASA's Ames Research Center in Moffett Field, Calif., the center that is managing the mission.

The mission's commissioning phase lasted roughly one month, a period in which the spacecraft remained in a high-altitude preliminary orbit and the instruments were turned on, checked and calibrated.

All three science instruments are in good health, according to the mission's payloads manager, Robert Caffrey at NASA's Goddard Space Flight Center in Greenbelt, Md. "The sensitivity of the instruments is very high, and we are looking forward to an exciting science phase!"

Спойлер

The Lunar Dust Experiment (LDEX), built to collect and analyze lunar dust particles in the moon's thin atmosphere, is fully operational. The instrument recorded its first dust hit within minutes after its cover was deployed on Oct. 16. In subsequent orbits, LDEX observed dozens of dust particles, indicating an impact rate on the order of one hit per minute. Preliminary analysis suggests the particle sizes are much smaller than one micrometer in radius.

The Ultraviolet and Visible Light Spectrometer (UVS), designed to probe the composition of the lunar atmosphere, made its first measurements shortly after the telescope door opened on Oct. 16. The instrument has been performing as expected and has conducted a series of pointing and instrument-performance calibrations, including looking at the limb of the moon and performing solar crossings by aiming the solar viewer at the sun and panning back and forth.

The Neutral Mass Spectrometer (NMS), which will measure variations in the lunar atmosphere over multiple lunar orbits, is operating normally. One of the first steps in getting the NMS ready for science measurements was to remove the cover of the instrument and expose the mass spectrometer to the lunar atmosphere.

To do this, a pyrotechnic device was commanded to fire, breaking a ceramic to metal to ceramic seal, and the cover flew away from the spacecraft. Sensors on the spacecraft detected a small amount of motion caused by this event, and measurements made before and after the cover deployment showed that trapped calibration gases had indeed been released to space.

In addition to the three science instruments, LADEE includes a Lunar Laser Communication Demonstration (LLCD) payload. LLCD has made history using a pulsed laser beam to transmit data over the 239,000 miles between the moon and Earth at a record-breaking download rate of 622 megabits per second (Mbps).

LLCD is NASA's first system for two-way communication using a laser instead of radio waves. It also has demonstrated an error-free data upload rate of 20 Mbps transmitted from the primary ground station in New Mexico to the spacecraft currently orbiting the moon.

"LLCD's goal is to validate and build confidence in the technology, so that future missions will consider using it," said Don Cornwell, LLCD manager at NASA's Goddard Space Flight Center in Greenbelt, Md. "The unique ability developed by the Massachusetts Institute of Technology's Lincoln Laboratory has incredible possibilities."

In addition to LLCD, LADEE marks several other firsts. The mission is the first flight of a spacecraft developed at Ames, the first spacecraft launched on a U.S. Air Force Minotaur V rocket integrated by Orbital Sciences Corp., and the first deep-space mission to launch from NASA's Wallops Flight Facility in Virginia.

[свернуть]

Now that the commissioning phase has ended, LADEE has lowered its orbit to get closer to the lunar surface and begin its 100-day science mission.

———
Dec 05, 2013

ЦитироватьМОСКВА, 3 фев — РИА Новости. НАСА продлило работу зонда LADEE на лунной орбите на 28 дней, это позволит снизить орбиту зонда до нескольких километров над лунной поверхностью и собрать еще больше научных данных, сообщает сайт SpaceRef.

"Запуск аппарата и выход на орбиту с использованием двигателей на борту LADEE были исключительно точны, поэтому у него осталось значительное количество топлива, что позволяет провести дополнительные исследования. Продление работы намного увеличит количество научных данных, которые даст этот проект", — пояснил менеджер проекта Батлер Хайн (Butler Hine) из Исследовательского центра Эймса в Майнтин-Вью, чьи слова приводятся на сайте.

Аппарат LADEE был запущен в космос в сентябре 2013 года. В октябре он прибыл к Луне, а 20 ноября вышел на низкую окололунную орбиту — от 12 до 60 километров над поверхностью спутника — и начал выполнять основную научную программу по изучению разреженной атмосферы Луны. Предполагалось, что этой работой он будет заниматься 100 дней. Теперь НАСА продлило работу зонда на орбите еще на 28 дней. LADEE совершит посадку приблизительно 21 апреля. Точная дата будет зависеть от финальной траектории зонда.

"Научная команда уже получила базовые данные о слабой лунной атмосфере, или экзосфере, и пылевых частицах. Один из плюсов продления (работы зонда), в том, что мы намереваемся снизить орбиту зонда до нескольких километров над лунной поверхностью. Это намного ниже, чем до сих пор", — отметил сотрудник проекта Рик Эльфик (Rick Elphic) из центра Эймса, чьи слова также приводит SpaceRef.

Проект LADEE (Lunar Atmosphere and Dust Environment Explorer) общей стоимостью 280 миллионов долларов предназначен для исследования крайне разреженной лунной атмосферы (экзосферы) и пылевых частиц у ее поверхности. Собранные данные помогут ученым судить об экзосфере Меркурия и других тел Солнечной системы. С помощью аппарата LADEE проводятся также эксперименты по лазерной связи между Луной и Землей.

Цитироватьsol пишет:
А интересно - до какой рекордно низкой высоты опустят орбиту.. вот бы до метров 500... (ну под конец, когда не жалко...)

ЦитироватьAlthough it is not equipped with photographic cameras, NASA's LADEE spacecraft has returned its first photos of the Moon from its vantage in low Lunar Orbit. Using its Star Trackers, LADEE snapped these images of the lunar surface on February 8, 2014 around 23:45 UTC.

The Star Trackers are specialized wide angle cameras that are used to identify stars – star tracker imagery is compared with star patterns through an onboard algorithm to precisely determine the spacecraft's three-axis attitude in space several times per minute. Not being able to produce the great photos that dedicated instruments can take of the Moon or other bodies, the star trackers can still provide exciting glimpses and give spacecraft a pair of eyes even through they are not carrying dedicated imagers.

Taken one minute apart, LADEE has traveled about 100 Kilometers in between the individual frames.

 (https://forum.novosti-kosmonavtiki.ru/forum/file/30966)
———
Spaceflight101 | February 15, 2014

ЦитироватьКосмический аппарат LADEE (Lunar Atmosphere and Dust Environment Explorer) постепенно снижает свою орбитальную высоту для того, чтобы продолжить проведение научных наблюдений перед запланированной на 21 апреля «встречей» с поверхностью Луны.

Руководители миссии на Земле, в Исследовательском Центре Эймса, управляют маневрами космического аппарата для того, чтобы он мог находиться над поверхностью Луны на расстоянии от 2 до 3 километров, собирая данные на максимально низкой высоте. Последний маневр будет проведен для того, чтобы траектория падения LADEE «привела» аппарат на дальнюю сторону Луны, которая находится вне зоны видимости землян.

Руководители миссии говорят, что маневры должны быть очень точно просчитаны, и даже в этом случае нельзя исключить возможность того, что LADEE опустится на поверхность Луны до 21 апреля, когда аппарат, по расчетам, должен исчерпать свой запас топлива.

До середины апреля двигатели LADEE будут включаться раз в неделю для того, чтобы обсерватория могла держаться на своей целевой орбите. 11 апреля аппарат выполнит свой последний маневр перед полным лунным затмением 15 апреля.

После затмения будет проведена диагностика работы аппарата. В том случае, если все будет хорошо, LADEE продолжит сбор и передачу научных данных.

ЦитироватьLADEE ‏@NASALADEE  (https://twitter.com/NASALADEE) 2 ч. (https://twitter.com/NASALADEE/status/457038146728099841)
Ground controllers @NASAAmes (https://twitter.com/NASAAmes) confirmed LADEE impacted the surface of the moon, as planned. Stay tuned for details! http://www.nasa.gov/ladee (http://t.co/4lc5OqSJkn)

Цитировать...in the coming months @LRO_NASA will to try & capture an image of the impact site

ЦитироватьАппарат LADEE (Lunar Atmosphere and Dust Environment Explorer /Исследователь лунной атмосферы и пылевого окружения) действительно «увидел свет» всего за несколько дней до того, как упасть на поверхность темной стороны Луны 17 апреля, в прошлый четверг. Специалисты миссии сделали все возможное, чтобы получить максимальное количество данных в то время, как аппарат летал на высоте всего несколько километров над поверхностью, и использовать по максимуму его уникальное положение для того, чтобы «посмотреть» в сторону горизонта, - так же, как это более 40 лет назад сделали астронавты миссии Apollo с лунной орбиты.

Ученые надеялись увидеть мягкое свечение зодиакального света - слабое свечение неба, простирающееся вдоль эклиптики, то есть в области Зодиака, с чем и связано название этого явления. На Земле зодиакальный свет выглядит, как конус, сужающийся с удалением от горизонта, постепенно теряющий яркость и переходящий в зодиакальную полосу – слабо светящийся пояс шириной около 10°, едва различимый на фоне ночного неба и тянущийся вдоль всей эклиптики, соединяя собой обе ветви зодиакального света – западную и восточную. Его можно наблюдать в течение пары часов после заката Солнца весной и перед восходом Солнца – осенью.

Так что же увидел LADEE? Желтый туман над горизонтом, который, расширяясь и рассеиваясь, превращается в свечение, которое слегка уклоняется в правую сторону. Это – зодиакальный свет и небольшое количество света, которое идет от внешней атмосферы Солнца – короны. Такое свечение называется «коронарный и зодиакальный свет». В самом конце над горизонтом взошло Солнце.

Однако, учение не увидели на снимках таинственных лучей, о которых упоминали некоторые астронавты Apollo. Эти лучи, зарисовку которых сделал астронавт Apollo 17 Юджин Цернан (Eugene Cernan) выглядят, как лучи света и тени, которые пробиваются через облака и называются сумеречными лучами.

Дело в том, что атмосфера Земли достаточно плотная, чтобы лучи могли пробиваться сквозь облака. А пыль в лунной атмосфере кажется слишком разреженной, чтобы то же самое могло бы произойти на Луне.

Считается, что пыль поднимается в атмосферу Луны благодаря воздействию электричества. Ультрафиолетовый свет Солнца выбивает электроны из атомов лунной пыли, придавая им положительный заряд. Так как одноименные заряды отталкиваются, частицы пыли отталкиваются друг от друга и двигаются в направлении наименьшего сопротивления: вверх. Чем меньше частица пыли, тем выше она поднимется перед тем, как упасть на поверхность. Возможно, именно эти «фонтаны» лунной пыли, подсвеченной Солнцем, и видели астронавты. В результате, LADEE увидел только тот самый коронарный и зодиакальный свет, и никаких лучей. Ученые планируют более внимательно последовательно изучить все снимки, сделанные аппаратом.

ЦитироватьWater Released from Moon During Meteor Showers

NASA Goddard (https://www.youtube.com/channel/UCAY-SMFNfynqz1bdoaV8BeQ)

Опубликовано: 15 апр. 2019 г.

Scientists have discovered that water is being released from the Moon during meteor showers. When a speck of comet debris strikes the Moon it vaporizes on impact, creating a shock wave in the lunar soil. For a sufficiently large impactor, this shock wave can breach the soil's dry upper layer and release water molecules from a hydrated layer below. The LADEE spacecraft detects these water molecules as they enter the tenuous lunar atmosphere, with peaks in the water signal correlating to known meteor showers on Earth. The discovery of water just beneath the Moon's surface provides a potential resource for future exploration, and it improves our understanding of the moon's geologic past and its continued evolution.

ЦитироватьАстрономы выяснили, как на Луне появляются "водяные облака"
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МОСКВА, 16 апр – РИА Новости. Появление паров воды над поверхностью Луны оказалось связано с ударами метеоритов, чьи падения растапливают и поднимают в безвоздушное пространство около 100-250 тонн влаги каждый год. К такому выводу пришли планетологи, опубликовавшие статью в журнале Nature Geoscience. (https://www.nature.com/articles/s41561-019-0345-3)

Цитировать"Вода и ее соединения практически полностью отсутствуют в экзосфере Луны. Мы, однако, смогли зафиксировать их появление в тот момент, когда ее поверхность бомбардировал один из метеорных потоков. Когда этот космическое шоу кончилось, вода тоже исчезла", — рассказывает Ричард Эльпик (Richard Elphic) из Исследовательского центра НАСА имени Эймса (США).

Как сегодня предполагают планетологи, Луна родилась в результате столкновения Тейи, протопланетного тела, с "зародышем" Земли. Столкновение привело к выбросу их совместных обломков в космос, из которой и была "слеплена" спутница нашей планеты.

Этот катаклизм считался причиной того, почему ее недра и поверхность практически лишены воды. Эта гипотеза была поставлена под сомнение в феврале 2012 года, когда ученые обнаружили неожиданно высокую концентрацию воды в лунных магматических породах.

Большие споры вызывают два ключевых вопроса - откуда взялась эта вода и где она прячется. Часть астрономов предполагает, что основным источником лунной влаги выступили кометы, тогда как другие приписывают эту роль астероидам, причем в пользу той и другой теории есть свои наборы доказательств.

Вдобавок, недавно ученые нашли большие залежи воды почти на всей поверхности Луны, что сделало эти споры еще более жаркими, а причину появления воды – еще более загадочной. Недавно планетологи нашли ответ на этот вопрос, обнаружив намеки на то, что почти все запасы воды у поверхности Луны попали туда в первые мгновения после ее формирования.

Открытия следов воды на Луне и подобные теоретические расчеты, как отмечает Эльпик, заставили его команду повторно проанализировать данные, которые собирал созданный ими зонд LADEE, отправленный пять лет назад на орбиту спутницы Земли для изучения ее атмосферы и пыли.

Благодаря крайне низкой орбите – он пролетал на расстоянии всего в 12 километров от Луны – LADEE изучал тайны ее "воздушной оболочки" чуть больше четырех месяцев. За это время он открыл сразу несколько странностей, в том числе необычно большое число частиц пыли на небольшой высоте от поверхности, а также своеобразные "облачка" из водяного пара.

Спойлер

Это открытие сразу заставило ученых спорить о происхождении данной воды и о том, существовала ли она в реальности, так как ее следы то появлялись, то исчезали из данных бортовых спектрометров LADEE.

Эльпик и его коллеги доказали, что эти облака не были своеобразным "космическим миражом" и выяснили, откуда взялась вода, проанализировав обстановку на Луне в те моменты, когда их следы возникали в данных зонда.

В общей сложности, зонд зафиксировал около семи сотен подобных "выбросов", каждый из которых ученые изучили, используя данные, которые собирали в то же время наземные телескопы и другие лунные зонды.

Анализируя эти события, ученые НАСА обратили внимание на странное стечение обстоятельств. Почти три дюжины самых крупных выбросов воды произошли в тот же самый момент, когда Луна пересекала орбиту одного из многочисленных метеорных потоков, периодически подсвечивающих атмосферу нашей планеты.

Сопоставив количество воды в экзосфере Луны с тем, как сильно бомбардировалась ее поверхность в момент появления подобных "облаков", ученые обнаружили, что сразу 29 самых крупных событий такого рода были связаны с метеорными потоками. Открытие этой связи, в свою очередь, помогло ученым раскрыть некоторые особенности лунных запасов влаги.

К примеру, учитывая типичные размеры метеоров, большие запасы воды должны встречаться в лунном грунте на глубинах, не превышающих примерно трех метров. Выше этой отметки находится относительно "сухой" слой, откуда вода исчезает под действием космических лучей и солнечного ветра. Это объясняет то, почему падения микрометеоритов не приводят к рождению аналогичных водяных облаков.

Заметно ниже нее, как предполагают геологи, находятся древние запасы лунного льда, постоянно подпитывающие эту водную прослойку, теряющую около 100-250 тонн воды каждый год. В пользу ее существования говорит то, что почва Луны не смогла бы накопить такие количества влаги, если бы ее единственным источником была материя солнечного ветра.

Это, как считают исследователи, говорит в пользу древнего происхождения запасов воды на Луне, чьи запасы постепенно истощаются с течением времени. Их открытие не только поможет оценить скорость этого процесса в прошлом, но и понять, смогут ли ими воспользоваться первые лунные колонисты, заключают ученые.

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ЦитироватьApril 15, 2019
RELEASE 19-03 (Goddard)

Meteoroid Strikes Eject Precious Water Fr om Moon

Researchers fr om NASA and the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, report that streams of meteoroids striking the Moon infuse the thin lunar atmosphere with a short-lived water vapor.

The findings will help scientists understand the history of lunar water — a potential resource for sustaining long term operations on the Moon and human exploration of deep space. Models had predicted that meteoroid impacts could release water fr om the Moon as a vapor, but scientists hadn't yet observed the phenomenon. 

Now, the team has found dozens of these events in data collected by NASA's Lunar Atmosphere and Dust Environment Explorer. LADEE (https://www.nasa.gov/ames/ladee/) was a robotic mission that orbited the Moon to gather detailed information about the structure and composition of the thin lunar atmosphere, and determine whether dust is lofted into the lunar sky.

Спойлер

https://www.youtube.com/watch?v=wZxUyH7vuRk (https://www.youtube.com/watch?v=wZxUyH7vuRk)
Scientists have discovered that water is being released from the moon during meteor showers. When a speck of comet debris strikes the moon it vaporizes on impact, creating a shock wave in the lunar soil. For a sufficiently large impactor, this shock wave can breach the soil's dry upper layer and release water molecules from the hydrated layer below. The LADEE spacecraft detects these water molecules as they enter the tenuous lunar atmosphere. This discovery provides a potential resource for future exploration, and it improves our understanding the moon's geologic past and its continued evolution.
Credits: NASA/Goddard/Dan Gallagher
Download video and images (https://svs.gsfc.nasa.gov/13078)

"We traced most of these events to known meteoroid streams, but the really surprising part is that we also found evidence of four meteoroid streams that were previously undiscovered," said Mehdi Benna of NASA's Goddard Space Flight Center in Greenbelt, Maryland, and the University of Maryland Baltimore County. Benna is the lead author of the study, published in Nature Geosciences (https://www.nature.com/articles/s41561-019-0345-3).

The newly identified meteoroid streams, observed by LADEE, occurred on Jan. 9, April 2, April 5 and April 9, 2014.

(https://img.novosti-kosmonavtiki.ru/207832.jpg) (https://www.nasa.gov/sites/default/files/thumbnails/image/ladee_web.jpg)
Artist's concept of the LADEE spacecraft (left) detecting water vapor from meteoroid impacts on the Moon (right).
Credits: NASA/Goddard/Conceptual Image Lab

There's evidence that the Moon has water (H2O) and hydroxyl (OH), a more reactive relative of H2O. But debates continue about the origins of the water, whether it is widely distributed and how much might be present.

"The Moon doesn't have significant amounts of H2O or OH in its atmosphere most of the time," said Richard Elphic, the LADEE project scientist at NASA's Ames Research Center in California's Silicon Valley. "But when the Moon passed through one of these meteoroid streams, enough vapor was ejected for us to detect it. And then, when the event was over, the H2O or OH went away."

Lunar scientists often use the term "water" to refer to both H2O and OH. Figuring out how much H2O and how much OH are present is something future Moon missions might address.

LADEE, which was built and managed by NASA's Ames Research Center in California's Silicon Valley, detected the vapor using its Neutral Mass Spectrometer, an instrument built by Goddard. The mission orbited the Moon from October 2013 to April 2014 and gathered detailed information about the structure and composition of the lunar atmosphere, or more correctly, the "exosphere" – a faint envelope of gases around the Moon.

To release water, the meteoroids had to penetrate at least 3 inches (8 centimeters) below the surface. Underneath this bone-dry top layer lies a thin transition layer, then a hydrated layer, wh ere water molecules likely stick to bits of soil and rock, called regolith.

From the measurements of water in the exosphere, the researchers calculated that the hydrated layer has a water concentration of about 200 to 500 parts per million, or about 0.02 to 0.05 percent by weight. This concentration is much drier than the driest terrestrial soil, and is consistent with earlier studies. It is so dry that one would need to process more than a metric ton of regolith in order to collect 16 ounces of water.

Because the material on the lunar surface is fluffy, even a meteoroid that's a fraction of an inch (5 millimeters) across can penetrate far enough to release a puff of vapor. With each impact, a small shock wave fans out and ejects water from the surrounding area.

When a stream of meteoroids rains down on the lunar surface, the liberated water will enter the exosphere and spread through it. About two-thirds of that vapor escapes into space, but about one-third lands back on the surface of the Moon.

(https://img.novosti-kosmonavtiki.ru/207733.jpg) (https://www.nasa.gov/sites/default/files/thumbnails/image/figure_3-infographic.jpg)
This infographic shows the lunar water cycle based on the new observations from the Neutral Mass Spectrometer on board the LADEE spacecraft. At the lunar surface, a dry layer overlays a hydrated layer. Water is liberated by shock waves from meteoroid impacts. The liberated water either escapes to space or is redeposited elsewh ere on the Moon. Some water is created by chemical reactions between the solar wind and the surface or delivered to the Moon by the meteoroids themselves. However, in order to sustain the water loss from meteoroid impacts, the hydrated layer requires replenishment from a deeper ancient water reservoir.
Credits: NASA Goddard/Mehdi Benna/Jay Friedlander

These findings could help explain the deposits of ice in cold traps in the dark reaches of craters near the poles. Most of the known water on the Moon is located in cold traps, wh ere temperatures are so low that water vapor and other volatiles that encounter the surface will remain stable for a very long time, perhaps up to several billion years. Meteoroid strikes can transport water both into and out of cold traps.

The team ruled out the possibility that all of the water detected came from the meteoroids themselves.

"We know that some of the water must be coming from the Moon, because the mass of water being released is greater than the water mass within the meteoroids coming in," said the second author of the paper, Dana Hurley of the Johns Hopkins University Applied Physics Laboratory.

The analysis indicates that meteoroid impacts release water faster than it can be produced from reactions that occur when the solar wind hits the lunar surface.

"The water being lost is likely ancient, either dating back to the formation of the Moon or deposited early in its history," said Benna.

NASA is leading a sustainable return to the Moon with commercial and international partners to expand human presence in space and bring back new knowledge and opportunities.

By Elizabeth Zubritsky

Bill Steigerwald / Nancy Jones
NASA's Goddard Space Flight Center (http://www.nasa.gov/goddard), Greenbelt, Md.
301-286-8955 / 301-286-0039
william.a.steigerwald@nasa.gov (mailto:william.a.steigerwald@nasa.gov) / nancy.n.jones@nasa.gov (mailto:nancy.n.jones@nasa.gov)

Alison Hawkes
NASA's Ames Research Center (https://www.nasa.gov/ames), Moffett Field, Calif.
650-499-9892
Alison.hawkes@nasa.gov (mailto:Alison.hawkes@nasa.gov)

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Last Updated: April 15, 2019
Editor: Bill Steigerwald