ICESat-II, ELaNa-XVIII: ELFIN, IT-SPINS, CHEFsat - Delta II 7420-10C - Vandenberg SLC-2W -15.09.2018

[tnt22]

[tnt22]

https://blogs.nasa.gov/icesat2/2018/09/13/icesat-2-proceeds-toward-launch-sept-15/

ICESat-2 Proceeds Toward Launch Sept. 15

Anna Heiney
Posted Sep 13, 2018 at 2:13 pm



NASA's Ice, Cloud and land Elevation Satellite-2, or ICESat-2, mission and launch teams today concluded a successful Launch Readiness Review. There are no technical issues being worked at this time. Teams are proceeding toward liftoff from California's Vandenberg Air Force Base on Saturday, Sept. 15, at 5:46 a.m. PDT (8:46 a.m. EDT) on a United Launch Alliance Delta II, the rocket's final mission.

ICESat-2 will measure the height of our changing Earth, one laser pulse at a time, 10,000 laser pulses per second. The satellite will carry a single instrument, the Advanced Topographic Laser Altimeter System (ATLAS), which measures the travel times of laser pulses to calculate the distance between the spacecraft and Earth's surface. ICESat-2 will provide scientists with height measurements that create a global portrait of Earth's third dimension, gathering data that can precisely track changes of terrain, including glaciers, sea ice and forests.

The U.S. Air Force 30th Space Wing weather officer indicated that they are predicting a 100 percent chance of favorable weather on launch day.

[tnt22]

Michael Baylor‏ @nextspaceflight 29 мин. назад

Weather is 100% go for the ICESat-2 launch on Saturday morning. In the event of a scrub, weather remains 100% go for Sunday. However, "patchy fog" will reduce visibility for spectators.

[tnt22]

https://www.teslarati.com/spacex-competitor-ula-final-launch-30-year-old-rocket/

SpaceX competitor ULA readies for final launch of 30-year-old Delta II rocket

By Eric Ralph
Posted on September 13, 2018

Long-time SpaceX competitor United Launch Alliance (ULA) is nearly ready for the final launch of its Boeing subsidiary's Delta II family of rockets, culminating a nearly 30-year history mostly dominated by routine success.

If completed without failure, the launch of NASA's ICESat-2 satellite – built to track global ice-sheet variation with a huge space-based laser – will mark Delta II's 100th consecutive success and the rocket's 153rd fully successful launch overall, an immensely impressive and laudable achievement regardless of the vehicle's lack of competitive advantage in the modern launch industry.

Спойлер

Chris B - NSF‏ @NASASpaceflight

A teary farewell to Delta II this weekend, so in the run up we're going to give her a send off with a trip down memory lane per the vehicle's evolution from Thor.

Standby for a 7,000 word (yep!) feature article from William Graham on Thursday, with a ton of cool info/old photos.



19:43 - 12 сент. 2018 г.

Shockingly tiny when compared with modern launch vehicles like Delta IV, Atlas V, and Falcon 9, Delta II measures roughly 39 meters (~128 ft) tall, 2.4 meters (8 ft) in diameter, and weighs 160 metric tons (~350,000 lb) when fully fueled, just over half as tall and significantly less than 30% as heavy as SpaceX's Falcon 9.

[свернуть]

Contracted by NASA in 2013, Delta II's ICESat-2 launch cost the agency roughly $97 million (2013 USD), although the cost of launch has shrunk in relation to the satellite, which suffered at least $200 million of overruns and 12+ months of delays due to difficulties developing the spacecraft's impressive space-based LIDAR system. For comparison, NASA contracted a Falcon 9 launch (for the TESS exoplanet observatory, launched in April 2018 ) from SpaceX for $87 million in 2016, while the USAF has secured several launch contracts with SpaceX for far more complex GPS satellite launches at a cost of almost exactly $97 million apiece.

Спойлер

The final Delta II rocket is awaiting its last launch from Vandenberg Air Force Base this Saturday. (NASA/Randy Beaudoin)


A Delta II Heavy rocket seen launching NASA's THEMIS satellite in 2007. (NASA)


Falcon 9 Block 5 booster B1049 returned to Port Canaveral today, ~60 hours after launch. Falcon 9 is dramatically cheaper than the aging Delta II. (Tom Cross)

AGING ROCKETS, CHANGING MARKETS

Put simply, the contrast in capabilities offered for equivalent prices soundly demonstrates exactly why Delta II is being phased out. Although capable of better performance with a third upper stage and nine much larger solid rocket boosters (SRBs), that 'Heavy' variant of Delta II cost NASA an incredible $150 million per launch in 2009. For the versions of Delta II closer to $100 million per launch, the rocket is able to place 2500-3200 kg (5500-7000 lb) in low Earth orbit and not much at all to any higher energy destinations, which demand a third stage or a heavier rocket. At a comparable price (or much lower in SpaceX's case), Atlas V and Falcon 9 are able to launch far larger payloads to far higher orbits.

This was by no means the case when Delta II debuted in 1989, and the McDonnell Douglas-built rocket readily earned its impressive reputation as a relatively reliable, capable, and (more or less) affordable launch vehicle compared alongside other rockets available in the '90s. Delta II wound up as a ULA rocket (sort of) thanks to Boeing and McDonnell Douglas' 1997 corporate merger, followed in 2006 by Lockheed Martin and Boeing's cooperative formation of the United Launch Alliance. ULA thus operates Delta II, Delta IV, and Atlas V, all featuring multiple variants and very few distinguishing capabilities when compared amongst themselves.


Delta II is trucked to the launch pad ahead prior to launch. (NASA)


The business end of Delta II. (ULA)


ULA technicians install one of four solid rocket boosters on ICESat-2's Delta II launch vehicle. (NASA)


ULA technicians install one of four solid rocket boosters on ICESat-2's Delta II launch vehicle. (NASA)
 
The cost of maintaining all those highly duplicative rockets and unique factories and engineering expertise is fundamentally unnatural and reliant upon some sort of noncompetitive market forces (i.e. launch monopolies assured through "block buys" of multiple rockets from NASA and the US military), forces that have been mortally challenged by SpaceX's reintroduction of competition to the American launch industry.

[свернуть]

ICESat-2 is scheduled to launch on Delta II on Saturday, September 15th at 5:46 AM PDT/12:46 UTC. Stay tuned for more information on ICESat-2's giant space LIDAR payload and mission goals, as well as Teslarati photographer Pauline Acalin's photos of the fairly historic rocket launch.

[tnt22]

Delta II ICESat-2 Mission Profile

United Launch Alliance

Опубликовано: 13 сент. 2018 г.

A United Launch Alliance Delta II Heavy rocket will launch NASA's Ice, Cloud and land Elevation-2 (ICESat-2) mission from Vandenberg Air Force Base, California. The ICESat-2 mission will be the final for the workhorse Delta II rocket, which has launched 154 times, including missions for the U.S. Air Force, NASA, the National Reconnaissance Office and commercial customers. Go Delta! Go ICESat-2!

(2:23)

[tnt22]

ULA‏Подлинная учетная запись @ulalaunch 17 ч. назад

NASA's #ICESat2 mission will launch to space aboard a ULA #DeltaII 7420-10 rocket. This 2-stage rocket has 4 solid rocket motors and a 10-foot-diameter composite fairing.

[tnt22]

D. Stamos/Helodriver‏ @SpacecoastPix 3 ч. назад

В ответ @NASASpaceflight @ulalaunch

A shot that closes the entire Thor Delta circle.

[tnt22]

https://blogs.nasa.gov/icesat2/2018/09/14/tower-rollback-friday-live-launch-coverage-saturday/

Tower Rollback Friday, Live Launch Coverage Saturday

Anna Heiney
Posted Sep 14, 2018 at 9:04 am



NASA's Ice, Cloud and land Elevation Satellite-2, or ICESat-2, a mission to measure the changing height of Earth's ice, is scheduled to launch Saturday, Sept. 15, with a 40-minute window opening at 5:46 a.m. PDT (8:46 a.m. EDT). The spacecraft will lift off from Space Launch Complex 2 (SLC-2) at Vandenberg Air Force Base in California on the final launch of a United Launch Alliance Delta II rocket. The U.S. Air Force 30th Space Wing weather officer reported they are predicting a 100 percent chance of favorable weather on launch day.

Be sure to follow along during the live coverage events below.

NASA EDGE Tower Rollback Show, Friday, Sept. 14, at 6 p.m. PDT (9 p.m. EDT)
Watch live at:
NASA TV: www.nasa.gov/nasalive
NASA EDGE Facebook: www.facebook.com/nasaedgefan
NASA LSP Facebook: www.facebook.com/NASALSP
NASA EDGE YouTube: www.youtube.com/NASAedge
NASA EDGE Ustream: www.usream.tv/nasaedge

Guests:
Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate in Washington
Doug McLennan, ICESat-2 project manager, NASA Goddard Space Flight Center
Kelly Brunt, ICESat-2 science team member, NASA Goddard Space Flight Center
Rex Engelhardt, mission manager, NASA's Launch Services Program
Mic Woltman, chief, Fleet Systems Integration Branch, NASA's Launch Services Program
Tim Dunn, launch director, NASA Kennedy Space Center
Tom Neumann, ICESat-2 deputy project scientist, NASA Goddard Space Flight Center
Donya Douglas-Bradshaw, ATLAS instrument project manager, NASA Goddard Space Flight Center
Dana VanDersaral, mission assurance team, United Launch Alliance

Live Launch Coverage, Saturday, Sept. 15, 5:10 a.m. PDT (8:10 a.m. EDT)
Join us for updates from the countdown, here on the blog and on NASA TV.

[tnt22]

https://spaceflightnow.com/2018/09/14/scientists-eager-to-renew-global-ice-measurements-with-nasas-icesat-2-mission/

Scientists eager to renew global ice measurements with ICESat 2 mission
September 14, 2018 | Stephen Clark


Artist's illustration of the ICESat 2 satellite and its six green laser beams designed to measure the height of ice sheets. Credit: NASA

The satellite awaiting launch early Saturday from California aboard the final flight of the venerable Delta 2 rocket should allow scientists to more precisely track changes in our planet's ice sheets, using six green laser beams to chart the height and slope of polar ice and glaciers, providing a key input into climate change research.

Researchers who plan to analyze data from the new satellite say a better understanding of Earth's ice will help them learn about our planet's changing climate, and help predict how melting ice will contribute to rising sea levels.

NASA's $1 billion ICESat 2 mission is set for liftoff at 5:46 a.m. EDT (8:46 a.m. EDT; 1246 GMT) from Vandenberg Air Force Base, a military-run spaceport on California's Central Coast between Los Angeles and San Francisco.

The satellite will ride into an orbit that flies pole-to-pole aboard the final flight of United Launch Alliance's Delta 2 rocket, a workhorse launcher with 154 missions in its pedigree that is now on the verge of retirement.

ICESat 2 stands for Ice, Cloud and land Elevation Satellite 2, a follow-on to NASA's ICESat mission which measured global ice sheets from 2003 until 2009. Equipped with a laser split into six beams, ICESat 2 will fly around 300 miles (500 kilometers) above the planet in an orbit tilted at a 92-degree angle to the equator, giving the mission coverage up to 88 degrees north and south latitude.

Featuring an improved laser instrument designed to provide more precise measurements than its predecessor, ICESat 2 will extend a data series which has shown ice is melting around the edges of Greenland and Antarctica, and is thinning in the oceans.

Спойлер

Technicians open and inspect the flight door to ICESat 2's laser instrument shortly after the spacecraft arrived at Vandenberg Air Force Base, California, in June. Credit: USAF 30th Space Wing/Timothy Trenkle

NASA in recent years has continued surveying ice heights with an airborne campaign called Operation Ice Bridge, showing some trends of melting ice detected by the ICESat satellite continued after that mission ended in 2009. But satellites like ICESat provide more uniform coverage.

"What we learned from ICESat about the ice sheets of Greenland and Antarctica is that they are particularly losing ice around coastal areas, which means, one, that they were losing ice, and also two, it was probably tied to changes occuring in the ocean," said Tom Wagner, NASA's cryosphere program scientist.

"With an aircraft, you can't make the same amount of measurements that you can by satellite," Wagner said. "What we found with Ice Bridge is that the changes observed by ICESat are not only continuing, but they appear to be accelerating in some cases."

That's important because ice conditions are linked to other factors that drive Earth's climate, such as currents and temperatures in the oceans. And rising sea levels could threaten cities along coastlines.

"In Antarctica and Greenland, we have about two-thirds of the Earth's fresh water," said Helen Fricker, a member of ICESat's science definition team at the Scripps Institution of Oceanography. "If all of that ice melted, we would raise global sea level on average by about 180 feet (54 feet), which is very significant."

Altimetry data collected by by the U.S.-French TOPEX/Poseidon and Jason series of satellites show the average global sea level rose by 77 millimeters (3 inches) from 1993 through 2017.


Artist's illustration of the ICESat 2 satellite. Credit: NASA

"ICESat 2 really is a revolutionary new tool for both land ice and sea ice research," said Tom Neumann, ICESat 2's deputy project scientist at NASA's Goddard Space Flight Center.

NASA has used satellites to look at ice for decades, but tracking ice coverage is easier than measuring the height, and estimating the thickness, of floating sea ice and ice caps covering land masses like Antarctica and Greenland.

Rather than relying on a single laser beam, as ICESat did, the new mission will fire six laser beams down to Earth and measure the time it takes for the light to bounce off the surface and back to a telescope on-board the spacecraft.

"To measure, or to estimate, the thickness of sea ice, ICESat 2 measures the height of the sea ice floating in the ocean and compares it with the height of the ocean water in cracks in the sea ice," Neumann said. "By comparing these two elevations, we can calculate the height of the sea ice sticking up out of the ocean water."

Only about a tenth of total sea ice sticks out above the ocean water line, so scientists can use ICESat 2's raw measurements to get a handle on the total thickness of the ice floating in the seas. Then scientists will use the ice height information in concert with gravity measurements from space using the GRACE Follow-On mission, which launched in May and helps scientists estimate the mass of the ice.

The ICESat 2 satellite was built by Northrop Grumman Innovation Systems, and its single instrument — the Advanced Topographic Laser Altimeter System, or ATLAS — was developed at NASA's Goddard Space Flight Center.

"ATLAS essentially acts like a stop watch," said Donya Douglas-Bradshaw, ATLAS instrument manager at Goddard. "The ATLAS laser fires 10,000 pulses per second with a trillion photons in each shot. Each time the laser fires, it starts the stop watch. It takes about 3.3 milliseconds for the beam to exit the instrument, reach the surface and return back to the telescope."

Only about a dozen or so photons will make it back to ICESat 2's receiving telescope, with the rest of the light scattering in the atmosphere or back into space.

The laser package "has the ability to time tag a single photon to billionth of a second accuracy," Douglas-Bradshaw said in a briefing with reporters. "This precision allows the instrument to detect annual changes in ice elevation on the order of half of a centimeter (0.2 inches)."

The photon-counting method is new, and development the ATLAS laser proved to be a challenge, delaying ICESat 2's launch more than two years, and adding several hundred million dollars to the mission's cost.

"The original ICESat mission went up, and the scientists looked at the data. They were very excited about that, and they came forward, and they said this mission has to do a lot of better things," said Doug McLennan, ICESat 2's project manager at Goddard. "This put the challenge to the engineering team to design a mission that could accmoplish those things. It was a very challenging mission to come up with the ATLAS instrument. It took longer than we thought, but now everything is buttoned up and sitting on top of that rocket and ready to go."

ICESat 2's ATLAS instrument actually includes two lasers, with a primary and a redundant emitter, and the pulses go through a diffractive optics element that splits the light into six green beams — each at a wavelength of 532 nanometers — spread across a swath of about 4 miles (6 kilometers) along the satellite's ground track.

The lasers will travel from the spacecraft down to Earth in pairs, each separated by about 300 feet (90 meters) to provide measurements of the average slope of ice. With 10,000 pulses per second — up from the 40 laser shots per second on the original ICESat mission, the ATLAS instrument will take a height measurement along its track at intervals of every 2.3 feet (70 centimeters) as the satellite travels at approximately 17,000 mph (27,000 kilometers per hour).

As ICESat 2 flies around the planet every hour-and-a-half, the Earth will rotate underneath the satellite's orbit, allowing the mission to measure global ice heights.

"We have an orbit that is an exact repeat of itself every 91 days," McLennan said. "That means we see the same piece of ice every three months. Every season, we get to measure what's happening on that piece of ice, and that allows us to accumulate a dataset year-over-year, from each season to the next."

The ICESat 2 satellite weighs around 3,340 pounds (1,515 kilograms) at launch, according to McLennan.

McLennan said the spacecraft has enough fuel to operate more than 10 years. ICESat 2's primary mission is scheduled for three years, but could be extended.

Scientists working in other Earth science disciplines will also get results from ICESat 2.

"ICESat 2 never turns off," said Lori Magruder from University of Texas at Austin, who led the mission's science definition team. "It operates all the time, so you get measurements over every single surface.

"We get measurements over the open ocean, and we also get measurements over inland water bodies," she said. "This is important because we don't have global measurements that can tell us about our Earth's reservoirs, so that informs certainly our knowledge of our planet's water storage."

The laser ranging instrument on ICESat 2 will also reveal new information about cloud structure as laser photons reflect back to the satellite, and the mission should also provide estimates of the heights of forests.

"From the vantage point of space, we'll get a global tree height measurement," Magruder said. "That allows us to create a global biomass estimate. Biomass is important becaause that informs our knowledge of the carbon cycle, and how that contributes to our environment and the climate."

[свернуть]

[tnt22]

NASA EDGE Live Stream

NASA EDGE

Трансляция началась 16 минут назад

[tnt22]

[tnt22]

[tnt22]

[tnt22]

https://spaceflightnow.com/2018/09/14/delta-2-icesat-2-mission-status-center/

Live coverage: Final Delta 2 rocket set for launch from California
September 14, 2018 / Stephen Clark

Updated: 09/15/2018 01:07 Stephen Clark

Launch preparations this week have gone like clockwork, according to NASA and United Launch Alliance Officials preparing for the Delta 2's final flight.

Last Friday, officials convened for a flight readiness review and agreed to proceed with the mission as scheduled. On Monday and Tuesday, ground crews working at Space Launch Complex 2-West, the Delta 2's launch pad at Vandenberg Air Force Base, loaded the rocket's second stage with its propellant supply of Aerozone 50 fuel, made by mixing hydrazine and unsymmetrical dimethyl-hydrazine, and nitrogen tetroxide oxidizer.

The toxic propellants will feed the second stage's Aerojet Rocketdyne AJ10 engine during four burns planned on Saturday's mission to carry NASA's ICESat 2 satellite and four tiny CubeSats into orbit.

The launch team also conducted a mission dress rehearsal Tuesday to practice countdown procedures, followed by final closeouts of the Delta 2 rocket, final conditioning of the ICESat 2 satellite's battery, and preparations for rollback of the launch pad's mobile gantry this evening.

Officials met again Thursday for a launch readiness review and determined all systems are "go" to begin the final countdown.

The mobile gantry at the SLC-2W launch pad overlooking the Pacific Ocean is scheduled around 6:45 p.m. PDT (9:45 p.m. EDT).

[tnt22]

09/15/2018 01:20 Stephen Clark

Weather forecasters don't expect conditions along California's Central Coast will stand in the way of the Delta 2 rocket's climb into orbit early Saturday, but spectators in the area hoping to glimpse the launch might be thwarted by clouds and fog.

The marine layer that typically blankets the coastline at Vandenberg Air Force Base is forecast to be in the area during Saturday's launch window, which opens at 5:46 a.m. PDT (8:46 a.m. EDT; 1246 GMT) and extends until 8:20 a.m. PDT (11:20 a.m. EDT; 1320 GMT).

Forecasters predict overcast clouds at about 1,000 feet, patchy fog with visibility around 2 or 3 miles, northerly winds of 10 to 15 knots, and a temperature between 52 and 57 degrees Fahrenheit.

There is a 0 percent chance weather will violate any the Delta 2's launch criteria, according to the official Air Force launch weather forecast.

[tnt22]

Tory Bruno‏Подлинная учетная запись @torybruno 3 ч. назад

Weather still looks good. Let's go to space.
#ICESat2

[tnt22]

[tnt22]

[tnt22]

[tnt22]