RBSP (x2) - Atlas V 401 - Canaveral SLC-41 - 30.08.2012 08:05 UTC

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30.08.2012 12:05:27.029 ЛМВ - RBSP (x2) - Atlas V 401 - Canaveral SLC-41

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Radiation Belt Storm Probes (RBSP)

http://rbsp.jhuapl.edu/
http://www.nasa.gov/mission_pages/rbsp/news/index.html
http://www.nasa.gov/mission_pages/rbsp/multimedia/img_gallery.html
http://www.nasa.gov/offices/ipce/ipao/home/rbsp_highlight.html

The Radiation Belt Storm Probes mission is part of NASA's Living With a Star Geospace program to explore fundamental processes that operate throughout the solar system, in particular those that generate hazardous space weather effects near the Earth and phenomena that could affect solar system exploration.

RBSP is being designed to help us understand the sun's influence on the Earth and near-Earth space by studying the planet's radiation belts on various scales of space and time.

Understanding the radiation belt environment and its variability has extremely important practical applications in the areas of spacecraft operations, spacecraft and spacecraft system design, mission planning, and astronaut safety.

The mission's science objectives are to:

# Discover which processes, singly or in combination, accelerate and transport radiation belt electrons and ions and under what conditions.
# Understand and quantify the loss of radiation belt electrons and determine the balance between competing acceleration and loss processes.
# Understand how the radiation belts change in the context of geomagnetic storms.

The instruments on the two RBSP spacecraft will provide the measurements needed to characterize and quantify the processes that produce relativistic ions and electrons. They will measure the properties of charged particles that comprise the Earth's radiation belts and the plasma waves that interact with them, the large-scale electric fields that transport them, and the magnetic field that guides them.

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http://www.nasa.gov/mission_pages/sunearth/news/RBSP-status.html

T-minus One Year
August 15, 2011

http://rbsp.jhuapl.edu/newscenter/intheloop/2011_08.php

August has been a busy month for the Radiation Belt Storm Probes and the scientists and engineers preparing the twin RBSP spacecraft (A and B) for their 2012 launch. On August 3, NASA approved a new launch readiness date of August 15, 2012 – exactly one year from today. With that new target date now officially on the calendar, the RBSP team at the Johns Hopkins Applied Physics Laboratory (APL) has recently achieved several major milestones with the integration and testing of the spacecraft.

 "We are nearly there with A, and B is only a few weeks behind," says Jim Stratton, systems engineer for RBSP at the Applied Physics Lab. "We're very close to having one complete spacecraft."

What were once bare black octagonal boxes are now recognizable as full-fledged spacecraft, each laden with propulsion systems, power and avionics systems. They're also (nearly) fully equipped with identical suites of five instruments – designed to survey the harsh environment of the radiation belts that surround Earth – from teams at the University of New Hampshire, University of Iowa, University of Minnesota, New Jersey Institute of Technology and the National Reconnaissance Office. The accompanying photos (right) show some of those instruments and sensors being attached to both spacecraft. While the final stages of spacecraft assembly occur in one cleanroom, A's and B's solar panels and boom assemblies await installation in a neighboring area.

After spacecraft A is completed this month, it's scheduled to undergo a September 12 balance test on the Lab's spin table; this will verify that the spacecraft is balanced correctly and will spin as designed while in orbit. At the end of September, A will begin its first comprehensive performance test (CPT), the spacecraft's first full-scale run-through of its operation. The CPT will simulate the entire range of operations that A and its instruments are designed to perform. November and December will bring more rigorous acoustic and thermal-vacuum testing schedules for both A and B. The spacecraft are set to be shipped from APL's Laurel, Md. facility to Cape Canaveral, Fla. on May 1, 2012.

Though building two identical spacecraft simultaneously has its challenges, it also has some benefits. "Spacecraft A hasn't always been first [for integration and testing]," Stratton explains. "We have a lot of overlap, and we're able to generate significant efficiencies and apply a lot of lessons learned."

Two mission simulations – run in May and July 2011– mimicked the period "from launch to early operation of the spacecraft," says Stratton. "Here at APL, we're using a new mission operations center, while the instrument teams are participating remotely from around the country, talking to their instruments aboard the spacecraft."

These instrument teams "collect data from their instruments just like they will in flight," he continues. "It's a great opportunity to check ground systems, hardware, and operations teams working together, and we've been very successful."

APL manages the RBSP mission for NASA and will operate the spacecraft; check back for more photos and updates as the mission moves toward launch in 2012.

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NASA's Radiation Belt Storm Probes Ready for Space Environment Tests
Twin spacecraft will explore sun's influence on Earth

December 5, 2011

NASA's Radiation Belt Storm Probes (RBSP), twin spacecraft being built and tested at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., are about to enter a challenging series of tests designed to certify that they are ready for their August 2012 launch and two-year mission in Earth's orbit. The coordinated measurements of the two RBSP spacecraft will advance our understanding of space weather and the sun's influence on the Earth and near-Earth space by probing the planet's radiation belts, which affect space weather and spacecraft operations.

Beginning the first week of December, RBSP will embark on a space environment test campaign that will last into March 2012. The RBSP team will subject the spacecraft to physical simulations of the stresses of launch and harshness of space operations, but in a controlled test facility where engineers can monitor the spacecrafts' condition.

"These are complex spacecraft, each with five very sensitive scientific instruments on board," says Jim Stratton, mission systems engineer for RBSP at the Applied Physics Lab. "The environmental tests are designed to really subject the spacecraft and systems to realistic, challenging conditions and make sure they are ready to fly."

The first test will simulate the incredibly loud noises generated during launch and the beginning of supersonic travel, when the launch vehicle passes through the sound barrier (approximately 770 miles per hour). These sounds, which can reach a maximum of 134 decibels (nearly as loud as a jet engine from 100 feet away), will be duplicated by a specialized speaker system that is controlled via computer to match the sonic profiles of launch and supersonic barrier breakthrough. The RBSP satellites will be mated together and placed at the center of a circular wall of powerful loudspeakers for this test. One of the substantial challenges for the probes is that they must survive launch as a single unit; later, above Earth, they will be separated and guided to their individual orbits.

RBSP will next undergo a vibration test. The spacecraft are mated together again and placed on a special table that will shake them to simulate the intense physical effects of launch, and make sure the probes' systems and electronics are secure and will operate post-launch.

In January 2012, the spacecraft will undergo an electromagnetic compatibility and interference test. This involves turning on all of the spacecrafts' internal systems without any external power or grounding to verify there are no electronic issues, and that RBSP can successfully perform its science-gathering mission.

RBSP will enter thermal vacuum testing in APL's test chambers in February. For five weeks, the craft will endure heating and cooling cycles in a vacuum environment; during the lengthy testing, RBSP will also undergo a 10 day-long mission simulation. After that, in May 2012, the completed RBSP spacecraft are scheduled to leave APL and travel south. "The next six months are all about continuing the tremendous efforts of the outstanding team we have assembled for this mission," says Rick Fitzgerald, program manager for RBSP at APL, "and getting ready to ship the spacecraft to Florida."

RBSP is scheduled for launch no earlier than Aug. 15, 2012, from the Kennedy Space Center, Fla. APL built the RBSP spacecraft for NASA and manages the mission. The RBSP mission is part of NASA's Living With a Star program, guided by the Heliophysics Division of the NASA Headquarters Science Mission Directorate in Washington. The program explores fundamental processes that operate throughout the solar system, in particular those that generate hazardous space weather effects near Earth and phenomena that could affect solar system exploration. Living With a Star is managed by NASA's Goddard Space Flight Center in Greenbelt, Md.

Learn more about the Radiation Belt Storm Probes, and see photos and videos of space environment testing, at http://rbsp.jhuapl.edu .

http://rbsp.jhuapl.edu/newscenter/newsArticles/20111205.php

NASA's Radiation Belt Storm Probes Ready for Space Environment Tests
12.14.11

NASA's Radiation Belt Storm Probes (RBSP) will soon enter a challenging series of tests to certify they are ready for their August 2012 launch and two-year mission in Earth's orbit. The two RBSP spacecraft will probe Earth's radiation belts, two bands of charged particles encircling our planet that can respond dramatically to increased radiation and energy from the sun causing space weather that can affect spacecraft and other man-made technologies.

During the space environment test campaign, the RBSP team at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. will subject the spacecraft to physical simulations of the stresses of launch and harshness of space operations, but in a controlled test facility where engineers can monitor the spacecrafts' conditions. The tests will begin the first week in December and will last into March 2012.

"These are complex spacecraft, each with five very sensitive scientific instruments on board," says Jim Stratton, mission systems engineer for RBSP at the Applied Physics Lab. "The environmental tests are designed to really subject the spacecraft and systems to realistic, challenging conditions and make sure they are ready to fly."

The first test will simulate the incredibly loud noises generated during launch and the beginning of supersonic travel, when the launch vehicle passes through the sound barrier (approximately 770 miles per hour). These sounds, which can reach a maximum of 134 decibels (nearly as loud as a jet engine from 100 feet away), will be duplicated by a specialized speaker system that is controlled via computer to match the sonic profiles of launch and supersonic barrier breakthrough. The RBSP satellites will be mated together and placed at the center of a circular wall of powerful loudspeakers for this test. One of the substantial challenges for the probes is that they must survive launch as a single unit; later, above Earth, they will be separated and guided to their individual orbits.

RBSP will next undergo a vibration test. The spacecraft are mated together again and placed on a special table that will shake them to simulate the intense physical effects of launch, and make sure the probes' systems and electronics are secure and will operate post-launch.

In January 2012, the spacecraft will undergo an electromagnetic compatibility and interference test. This involves turning on all of the spacecrafts' internal systems without any external power or grounding to verify there are no electronic issues, and that RBSP can successfully perform its science-gathering mission.

RBSP will enter thermal vacuum testing in APL's test chambers in February. For five weeks, the craft will endure heating and cooling cycles in a vacuum environment; during the lengthy testing, RBSP will also undergo a 10 day-long mission simulation. After that, in May 2012, the completed RBSP spacecraft are scheduled to leave APL and travel south.

"This is an exciting time for the RBSP program," says David Sibeck the project scientist for RBSP at NASA's Goddard Space Flight Center in Greenbelt, Md. "APL is making sure the spacecraft are ready for flight and we're looking forward to the launch next year. RBSP will provide the first multi-point measurements of this little-explored region — a region that responds to energy from the sun in often dramatic ways that we don't yet understand."

RBSP is scheduled for launch no earlier than Aug. 15, 2012, from the Kennedy Space Center, Fla. APL is building the RBSP spacecraft for NASA and will manage the mission. The RBSP mission is part of NASA's Living With a Star program, guided by the Heliophysics Division of the NASA Headquarters Science Mission Directorate in Washington. The program explores fundamental processes that operate throughout the solar system, in particular those that generate hazardous space weather effects near Earth and phenomena that could affect solar system exploration. Living With a Star is managed by NASA's Goddard Space Flight Center in Greenbelt, Md.

http://www.nasa.gov/mission_pages/rbsp/news/ready-SET.html

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Spacecraft Instruments

The Applied Physics Laboratory will build and operate the twin RBSP spacecraft for NASA's Living With a Star program.

The RBSP spacecraft will operate entirely within the radiation belts throughout their mission. When intense space weather occurs and the density and energy of particles within the belts increases, the probes will not have the luxury of going into a safe mode, as many other spacecraft must do during storms. The spacecraft engineers must therefore design probes and instruments that are "hardened" to continue working even in the harshest conditions.

The probes will carry a number of instruments and instrument suites to support five experiments that will address the mission's science objectives. Because it is vital that the two craft make identical measurements to observe changes in the radiation belts through both space and time, each probe will carry the following:

    * Energetic Particle, Composition, and Thermal Plasma Suite (ECT)
      Principal Investigator: H. Spence, University of New Hampshire

    * Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS)
      Principal Investigator: C. Kletzing, University of Iowa, Iowa City

    * Electric Field and Waves Suite (EFW)
      Principal Investigator: J. Wygant, University of Minnesota, Minneapolis

    * Radiation Belt Storm Probes Ion Composition Experiment (RBSPICE)
      Principal Investigator: L. Lanzerotti, New Jersey Institute of Technology

    * Relativistic Proton Spectrometer (RPS)
      Principal Investigator: National Reconnaissance Office

http://rbsp.jhuapl.edu/spacecraft/instruments/index.php

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NASA's THEMIS Satellite Sees a Great Electron Escape
01.30.12

When scientists discovered two great swaths of radiation encircling Earth in the 1950s, it spawned over-the-top fears about "killer electrons" and space radiation effects on Earthlings. The fears were soon quieted: the radiation doesn't reach Earth, though it can affect satellites and humans moving through the belts. Nevertheless, many mysteries about the belts – now known as the Van Allen Radiation belts – remain to this day.

Filled with electrons and energetic charged particles, the radiation belts swell and shrink in response to incoming solar energy, but no one is quite sure how. Indeed, what appears to be the same type of incoming energy has been known to cause entirely different responses on different occasions, causing increased particles in one case and particle loss in another. Theories on just what causes the belts to swell or shrink abound, with little hard evidence to distinguish between them. One big question has simply been to determine if, when the belts shrink, particles escape up and out into interplanetary space or down toward Earth. Now, a new study using multiple spacecraft simultaneously has tracked the particles and determined the escape direction for at least one event: up.

"For a long time, it was thought particles would precipitate downward out of the belts," says Drew Turner, a scientist at the University of California, Los Angeles, and first author on a paper on these results appearing onine in Nature Physics on January 29, 2012 date. "But more recently, researchers theorized that maybe particles could sweep outward. Our results for this event are clear: we saw no increase in downward precipitation."

While it may sound like a simple detail, such knowledge is not just esoteric. Indeed, the study of particle losses in the belts has so far provided more mystery and potential theories than concrete information. But understanding the radiation belts – and how they change as particles and energy come in or go out -- is a crucial part of protecting satellites that fly through the region.

The Van Allen belts fit into a larger system that stretches from the sun to Earth. The sun sends out a constant stream of solar wind, not to mention occasional much larger bursts – such as explosions from the sun's atmosphere called coronal mass ejections (CMEs) or shock fronts caused by fast solar winds overtaking slower winds called corotating interaction regions (CIRs).

When these bursts of energy move toward Earth, they can disturb Earth's own magnetic environment, known as the magnetosphere, and create a geomagnetic storm. Sometimes these storms can cause a sudden drop in the radiation belt particles, seemingly emptying the belt in only a few hours. This "drop out" can last for days. What causes the drop out, why it lasts so long, and just how the particles even leave remain unanswered questions.



http://www.nasa.gov/images/content/512181main_rbsp-orig_full.jpg

Artist concept of the twin Radiation Belt Storm Probes spacecraft, scheduled for launch in August 2012. Credit: NASA

Solving such a mystery requires numerous spacecraft measuring changes at several points in space to determine whether an event in one place affects an event elsewhere. The Radiation Belt Storm Probes (RBSP), scheduled to launch in August 2012, are specifically geared for such observations, but in the meantime, a team of scientists have brought together two disparate sets of a spacecraft to get an early multipoint view of the radiation belts during an event when the belts experienced a sudden loss of particles.

"We are entering an era where multi-spacecraft are key," says Vassilis Angelopoulos, a space scientist at UCLA, and the principal investigator for THEMIS and a coauthor on the paper. "Being able to unite a fleet of available resources into one study is becoming more of a necessity to turn a corner in our understanding of Earth's environment."



In this case, the team observed a small geomagnetic storm on January 6, 2011 using the three NASA THEMIS (Time History of Events and Macroscale Interactions during Substorms) spacecraft, two GOES (Geostationary Operational Environment Satellite), operated by the National Oceanic and Atmospheric Administration (NOAA), and six POES (Polar Operational Environmental Satellite), run jointly by NOAA, and the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT) spacecraft.

The THEMIS and GOES spacecraft orbit around Earth's equatorial region, while the POES spacecraft orbit at lower altitude near the poles and travel through the radiation belts several times per day. All are equipped to study the energetic particles in the region. The observations provided an unprecedented view of a geomagnetic storm from numerous viewpoints simultaneously – and the team found unequivocally that particles escaped the radiation belts by streaming out into space, not by raining down toward Earth.

During this storm, electrons moving near the speed of light dropped out for over six hours. In that time period POES saw no increase in electrons escaping downward from the belts. On the other hand, the spacecraft did monitor a low-density patch of the belt that first appeared at the outer edges of the belts and then moved inward. This sequence is consistent with the notion that particles were streaming outward, just as the low density region of cars leaving from the front of a traffic jam moves backward over time as more and more cars are able to move forward and escape.

"This was a very simple storm," says Turner. "It's not an extreme case, so we think it's probably pretty typical of what happens in general and ongoing results from concurrent statistical studies support this."

If, indeed, electrons usually escape the radiation belts by streaming outward, it seems likely that some kind of waves aid and abet their outward motion, enabling them to reach the outer escape boundary. Hammering out this escape mechanism will be one of the jobs for RBSP, says David Sibeck at NASA's Goddard Space Flight Center in Greenbelt, Md., who is NASA's mission scientist for RBSP and project scientist for THEMIS.

"This kind of research is a key to understanding, and eventually predicting, hazardous events in the Earth's radiation belts," says Sibeck. "It's a great comprehensive example of what we can expect to see throughout the forthcoming RBSP mission."

For more information about the associated missions, visit:

http://www.nasa.gov/themis
http://goespoes.gsfc.nasa.gov/
http://www.nasa.gov/rbsp

http://www.nasa.gov/mission_pages/themis/news/electron-escape.html

На русском:

Солнце сдувает околоземные электроны-"убийцы" во время магнитных бурь

МОСКВА, 29 янв - РИА Новости. Солнечный ветер оказался виновником таинственного исчезновения электронов-"убийц" из радиационных поясов ван Аллена - двух областей околоземного пространства, в которых содержится большое количество заряженных частиц высоких энергий, во время геомагнитных бурь, заявляют американские астрономы в статье, опубликованной в журнале Nature Physics.

Пояса высокоэнергетических частиц были открыты американским астрофизиком Джеймсом ван Алленом в 1958 году при помощи приборов первого в истории исследовательского спутника "Эксплорер-1" (Explorer-1). Электроны и другие частицы высокой энергии в этих областях околоземного пространства смертельно опасны для спутников и представляют серьезную угрозу для автоматических и пилотируемых космических аппаратов.

"Во время начала геомагнитного шторма, практически все электроны, пойманные силой пояса ван Аллена, исчезают из него и возвращаются обратно через несколько часов. Такое поведение всегда приводило нас в замешательство - представьте, что океаны Земли осушаются за одну секунду и через час они восстанавливают свои запасы воды", - пояснил один из участников исследовательской группы Вассилис Ангелопулос (Vassilis Angelopoulos) из университета штата Калифорния в Лос-Анджелесе (США).

Группа астрофизиков под руководством Дрю Тернера (Drew Turner) из университета штата Калифорния в Лос-Анджелесе попыталась найти причину побега электронов-"убийц" из радиационных поясов, изучив данные, собранные спутниками THEMIS, GOES и NOAA-POES во время геомагнитных бурь.

Тернер и его коллеги изучили последствия одной из недавних магнитных бурь, которая произошла 6 января 2011 года. В этот день сразу несколько спутников зафиксировало сокращение числа высокоэнергетических частиц в поясах ван Аллена. "Очистка" радиационных поясов шла сверху вниз - первым исчезло "население" высоких этажей облака частиц, тогда как нижняя часть поясов исчезла только к пику геомагнитной бури.

Как считают физики, полное отсутствие самых быстрых электронов даже через несколько часов после завершения бури указывает на то, что в исчезновении электронов-"убийц" виновато взаимодействие Солнца и магнитосферы Земли.

По словам физиков, столкновение магнитосферы Земли и области сжатия - пограничного слоя между "быстрым" и "медленным" участками солнечного ветра - приводит к резкому сокращению границы поясов. Благодаря этому самые быстрые электроны "выпадают" из зоны влияния магнитного поля Земли и теряют скорость, сталкиваясь с потоком солнечного ветра. Это приводит к очистке поясов от львиной доли частиц высокой энергии, захваченных магнитным полем планеты.

Астрофизики полагают, что выводы их работы помогут улучшить точность предсказаний космической погоды. Кроме того, авторы статьи планируют продолжить исследования поясов ван Аллена совместно с коллегами из Московского государственного университета при помощи исследовательского спутника "Ломоносов", запуск которого намечен на весну 2012 года.

http://ria.ru/science/20120129/551934306.html

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ВИДЕО: http://rbsp.jhuapl.edu/newscenter/newsArticles/20120207.php

It's All in the Swing: RBSP Undergoes Magnetic Swing Test
February 7, 2012

With NASA's Radiation Belt Storm Probes scheduled to launch in fewer than 200 days, the pace of spacecraft testing has continued to ramp up. In mid-January, RBSP – built for NASA by the Johns Hopkins University Applied Physics Lab (APL) in Laurel, Md. – was subjected to a science test that ensures the spacecraft is magnetically clean when it begins its mission. This is done so that one of RBSP's five instruments, the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS), can properly gather data. EMFISIS will help scientists understand the important role played by magnetic fields and plasma waves in the processes of radiation belt particle acceleration and loss.

EMFISIS uses two types of magnetometers; each is fixed to the end of a three meter long boom that deploys from two of the RBSP's solar panels. One type of magnetometer is used by RBSP's science team to study distortions in Earth's magnetic field that affect the Van Allen radiation belts. It also uses the planet's magnetic field to estimate the spacecrafts' attitude (the orientation in space of the probe); it's therefore very important that the magnetic field generated by spacecraft is so small that it will not affect these crucial measurements.

"EMFISIS has very sensitive magnetometers," explains APL's Nelli Mosavi, the lead engineer for the RBSP magnetic swing test. "We need to make sure that RBSP is very magnetically clean. In order to meet the tight magnetic requirement for RBSP, from the start of the project, we had a very strict commitment to the material and component selection. All components, subsystems and instruments were magnetically 'sniffed' [evaluated] prior to spacecraft integration." RBSP must have a static magnetic field of less than five nanotesla (a nanotesla is a billionth of a tesla, the measurement of magnetic field strength) at the end of the three-meter-long boom where EMFISIS will be mounted; for comparison, a typical refrigerator magnet generates about 5,000,000 nanotesla at the point it adheres to your refrigerator.

Mosavi explains the January 23 swing test of spacecraft A, shown in the video at top:

"The one tripod to the left of the spacecraft has two APL magnetometers, which use a laser pointer as a range finder," Mosavi says. "On the right are two tripods, each with two magnetometers from NASA's Goddard Space Flight Center. Those use ultrasonic range finders that communicate with the magnetometers via Bluetooth. Prior to starting the spacecraft swinging, it is necessary to create a timing synchronization for all the magnetometers. In order to do that, a circular coil of wound wire is placed underneath the spacecraft. A current is briefly sent through the windings, which generates a magnetic field pulse that is recorded by all the magnetometers, providing the necessary timing synchronization for the analysis."

Mosavi explains why rangefinders are needed, and why it was good to have different magnetometers in the setups: "It's important to have the real time distance measurements on the motion of the spacecraft with respect to the test magnetometers," she says, "and having test magnetometers in different orientations and positions ensures complete coverage of the spacecraft magnetic field."

To accurately characterize the magnetic field of the RBSP spacecraft, it must be in motion. That's why the probes were carefully rigged and suspended from a crane hook, and manually coaxed into a pendular motion with a push from an RBSP engineer. "A total of 12 pendulum oscillation sets of measurements were taken. For each set, the first four or five swings are the most important, because the spacecraft gets closest to the test magnetometers," says Mosavi. Each swing is about one-half inch lower than the last, and data is taken until the spacecraft comes to a nearly complete stop.

Magnetometer swing testing on both spacecraft was completed in late January, and "initial measurements indicated that the spacecraft are indeed below the threshold," Mosavi says.

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THEMIS Celebrates Five Years of Watching Aurora and Space Weather

People still talk about the launch. It was the first – and so far, only – time NASA has launched five satellites at one time. Carefully balanced inside a Delta II rocket, the five THEMIS (short for Timed History of Events and Macroscale Interactions during Substorms) spacecraft were launched into space from Cape Canaveral at 6:01 p.m. ET on February 17, 2007. The spacecraft were nestled in a ring shape, four around the outside and one on a middle pedestal. A critical sequencing guided how each spacecraft launched into space, first the top one, then the ones on the outside, so the platform would remain balanced and stable.

"The launch of THEMIS was one of the first Explorer missions I oversaw from concept through launch and on-orbit checkout and it still stands out in my mind," says Willis Jenkins, the Program Executive for NASA's Explorers Program, a program that supports less expensive and highly focused missions. "Trying to get five spacecraft together on one rocket was a challenge, but our team came up with unique ways to build and launch them."

Those five satellites working in tandem was crucial for THEMIS' job of tracking energy as it moves through space. Energy and radiation from the sun impacts and changes Earth's magnetic environment, the magnetosphere, and such impacts cause "space weather" that can harm satellites in space. As they orbit around Earth, the THEMIS satellites work together to gather data on how any given space weather event travels through space – something impossible to understand with a single spacecraft, which cannot differentiate between an occurrence that happens throughout space, rather than in a single location. Since 2007, the THEMIS satellites have reinvigorated studies of the magnetosphere, mapping the details of how explosive auroras occur, how the solar wind transfers energy to Earth's space environment, and how chirping waves in space relate to blinking auroras on Earth.

During its prime, two-year mission, THEMIS' main objective was to pinpoint where a space weather phenomenon known as substorms originate. Substorms generate aurora, but before THEMIS launched no one knew exactly what created the onset of a substorm.

"Five years ago, the state of the field could be described in one word: confusion," says Vassilis Angelopoulos, a space scientist at the University of California, Los Angeles, and the principal investigator for THEMIS. "We didn't understand the chain that linked energy from the sun to the aurora. We didn't know what mechanism caused substorms. We didn't know where, in the vast area of space, the process happened."

THEMIS answered those questions early on. Using its five satellites, as well as an array of some 25 ground based instruments, the THEMIS team could watch how the substorms formed and how they correlated to events in the night sky.

Together, the instruments painted a complete picture of aurora formation. A diffuse, weak aurora is always present near the poles, but can't always be seen with the naked eye. Brighter ones require an influx of energy from the sun that starts when the solar wind's magnetic field swings around, in the opposite direction of Earth's own magnetic field. Under such conditions, the solar wind rips off Earth's magnetic field lines from the day side, pulling them around to the night side, where they pile up, storing vast amounts of energy until they release in explosive bursts of magnetic reconnection. The surge of radiation and magnetism that rebounds toward Earth in this case is a substorm, complete with its attendant aurora.

After the first two years, NASA extended the THEMIS mission, which went on to track other space weather processes as they travel near Earth. THEMIS discovered the critical importance of something called "dipolarization fronts," bursts of material and energy that collapse Earth's magnetic field at the beginning of a substorm. These fronts are blobs of magnetized material, or plasma, with temperatures of one million degrees and speeds of one million miles per hour that race toward Earth. THEMIS satellites have observed them ramming into the near-Earth region, injecting hyper fast electrons -- which can damage computer systems -- into the region of space where geosynchronous satellites reside with their sensitive electronics.

Scientists have also compared THEMIS space and ground-based data to solve a long standing space mystery of what caused "pulsating" aurora, beautiful emission patterns in which the aurora appear to blink. The aurora's pulses corresponded perfectly to something much higher in space called "chorus waves," so-called because in ground radio receivers they sound like a chorus of chirping bird-songs.



http://www.nasa.gov/images/content/623736main_ari_still_noAurora.jpg

In additional to the five THEMIS spacecraft launched into space, 20 THEMIS ground stations can observe aurora from the ground. Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio

"With five satellites we've been able to pin down the topology and structure of the magnetosphere," says David Sibeck, the project scientist for THEMIS at NASA's Goddard Space Flight Center in Greenbelt, Md. "THEMIS truly mapped out how the magnetic fields outside the magnetosphere append to Earth's magnetic boundaries, transferring energy and material into our system."

With five years under its belt, two new opportunities have opened up THEMIS' research potential beyond the original substorm question. First, two of the original THEMIS satellites have been moved into a new orbit around the moon and have been renamed the ARTEMIS mission. The technical details of moving those two satellites with minimal fuel and numerous gravity assists made orbital flight history as much as the original launch of five spacecraft did. And, as NASA's Jenkins points out, using one Explorer project for two separate missions translates to a great savings in cost.

"Re-purposing this Explorer stands as a prime example of a cost effective mission with a large return on the investment," says Jenkins. "It is a win-win adventure for everyone."

The three THEMIS satellites around Earth are gearing up to add another focus to its mission as well: helping to track energy swells from out in space all the way into the two great belts of radiation – known as the Van Allen Radiation Belts – that surround Earth.

In the second half of 2012, NASA will launch two new spacecraft, the Radiation Belt Storm Probes (RBSP) that will specifically be studying this region and how the belts swell and shrink in response to outside effects. In 2014, NASA will launch four spacecraft called the Magnetospheric Multiscale mission (MMS) that will study the physics of magnetic reconnection at the boundaries of the magnetosphere. The orbit for THEMIS lies in between the orbits for RBSP and MMS. THEMIS has the potential to unify observations from these missions into a nine-satellite global constellation to observe the entire course of energy release – from the entire length of its travels from the edges of the magnetosphere to impact with the near-Earth space that is crowded with satellites vulnerable to incoming space weather.

"This kind of operation heralds a new way of conducting space observations by combining the scientific benefits of new hardware with older, but powerful and well-tested satellites," says Angelopoulos. "We have the promise of a qualitative change in our understanding of space weather phenomena, today more than ever before."

For more information about the associated missions, visit:

http://www.nasa.gov/themis
http://www.nasa.gov/artemis
http://www.nasa.gov/rbsp
http://rbsp.jhuapl.edu/

http://www.nasa.gov/mission_pages/themis/news/five-years.html

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RBSP Enters Thermal Vacuum Testing
February 23, 2012

On Feb. 21, NASA's twin Radiation Belt Storm Probe satellites began what will be a six-week test of their ability to perform in the harsh conditions of space. The fully-assembled spacecraft (minus their solar panel arrays and instrument booms) were carefully raised and sealed into two identical thermal vacuum testing chambers at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md.

These chambers duplicate the airless vacuum of space and the temperature extremes in which RBSP will perform after launch in August 2012. The spacecraft will operate under power while inside the test chambers to ensure that the electronics and mechanical systems are performing as designed. In the coming weeks, a mission simulation will be conducted that will put the spacecraft through a 10-day work cycle set in "Feb. 2013;" this lengthy test will provide engineers and scientists with more information about RBSP's capabilities while operating in conditions nearly identical to those above the Earth.

Look for more stories and details about this crucial phase of RBSP testing in the coming weeks.

During RBSP's two year primary mission, the probes will help scientists study the Van Allen radiation belts which surround our planet, and learn more about the processes that create them and cause them to vary in size and intensity.

RBSP is scheduled for launch no earlier than Aug. 15, 2012, from the Kennedy Space Center, Fla. APL built the RBSP spacecraft for NASA and manages the mission. The RBSP mission is part of NASA's Living With a Star program, guided by the Heliophysics Division of the NASA Headquarters Science Mission Directorate in Washington.

http://rbsp.jhuapl.edu/newscenter/intheloop/2012_0223.php

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Кликабельно



NASA's RBSP spacecraft A is ready to be raised into the thermal vacuum test chamber at the Johns Hopkins University Applied Physics Lab for what will be six weeks of testing. CREDIT: NASA/JHUAPL



At the chamber to the left of spacecraft A, spacecraft B is also ready to begin testing that will simulate the harsh temperature swings and airless vacuum of space. CREDIT: NASA/JHUAPL



APL's RBSP team carefully raise spacecraft A upward and into the thermal vacuum test chamber. CREDIT: NASA/JHUAPL



Nearly there: RBSP spacecraft A has almost completed its ascent into the test chamber. CREDIT: NASA/JHUAPL



Both RBSP spacecraft are now successfully sealed into their thermal vacuum test chambers. CREDIT: NASA/JHUAPL

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ВИДЕО: http://rbsp.jhuapl.edu/newscenter/intheloop/2012_0301.php

Loading RBSP Into Thermal Vacuum Testing: The One-Minute Video Version
March 1, 2012

This one-minute video, taken on Feb. 21, is a compressed version of the loading of NASA's twin Radiation Belt Storm Probe satellites into two identical thermal vacuum testing chambers. The process of actually lifting the spacecraft into the chambers took less than half an hour, and followed many days of preparation by the RBSP team at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md.

The video first shows RBSP spacecraft A being wheeled into position below the right thermal vacuum chamber, then slowly raised by a hydraulic lift into the chamber. The RBSP team raises the spacecraft slowly and steadily in part because the clearance between RBSP and the sides of the chamber is small (around one inch). The many foil-wrapped cables visible in these shots carry power to and data from the spacecraft, and connect to the spacecraft via cylindrical chamber feed-throughs (easily seen by their red connector covers). Finally, the chambers themselves are shown (spacecraft B is in the left chamber, A in the right); these will be RBSP's homes for the next six weeks while the spacecraft perform rigorous performance tests and simulate normal science operations – all while being subjected to extreme temperature variations in an airless environment to make sure the probes are ready to handle the harsh conditions of space.

During RBSP's two year primary mission, the probes will help scientists study the Van Allen radiation belts which surround our planet, and learn more about the processes that create them and cause them to vary in size and intensity.

RBSP is scheduled for launch no earlier than Aug. 15, 2012, from the Kennedy Space Center, Fla. APL built the RBSP spacecraft for NASA and manages the mission. The RBSP mission is part of NASA's Living With a Star program, guided by the Heliophysics Division of the NASA Headquarters Science Mission Directorate in Washington.

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Time Traveling: Simulation Creates '10 Days in the Life' of RBSP, circa 2013

In APL's newest mission operations center (MOC) – specifically designed to operate two spacecraft at one time – RBSP project engineers monitor data during a simulation of normal science operations for the twin spacecraft, which are sealed in thermal vacuum testing chambers that simulate the extremes of the space environment. During a 10-day, 24-hour-a-day mission simulation designed to take place from Feb. 13-23, 2013, the team will also simulate two spacecraft maneuvers: one to best align RBSP's solar panels to the sun, and the other to avoid a potential collision with another object in orbit.

With the integration and testing of NASA's Radiation Belt Storm Probes complete, and the twin spacecraft sealed within thermal vacuum testing chambers for six weeks of rigorous space environment simulation, another part of the RBSP team is busy ensuring that the spacecraft will successfully perform their science gathering mission after launch in August 2012.

On March 13, the RBSP team at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., began a 10-day-long mission simulation designed to end March 22, 2012. It is the third such simulation to date, but the first full systems test, and it will put the instruments and RBSP control systems through every phase of operation during the period designated as February 13-23, 2013. "This test puts both spacecraft, as a system, through the paces they will go through during the mission," says Ray Harvey, RBSP mission operations manager, and lead ground segment system engineer.

"It's a 24-hour-a-day simulation of both spacecraft in their routine science operations phase, about six months after launch," Harvey explains. "We're operating both spacecraft from the newest mission operations center [MOC] here at APL, using the same hardware and software, and same processes and procedures, that we'll use after the actual launch." Operating the instruments while they are in thermal vacuum testing is a key verification of the systems' capabilities (an RBSP team stationed by the thermal vacuum chambers monitors the spacecraft at all times, including during the simulation).

Proving Processes
The mission simulation, run entirely from the MOC, recreates almost every detail of the day-to-day science operation of RBSP so that engineers and scientists can make sure their plans and equipment will function once the spacecraft are in orbit, which will vary from approximately 600 kilometers (about 311 miles) to 30,600 kilometers (about 19,014 miles) above the Earth. "We're working to validate our concepts for operations," says Harvey. "We're sending commands to the spacecraft, then bringing science data down to the ground. This 10-day test will really prove out our process. There are more than 400 requirements we'll be verifying during the test."

The science instrument teams – located at the University of New Hampshire, University of Iowa, University of Minnesota, New Jersey Institute of Technology and the National Reconnaissance Office in Virginia – will be sending commands to the MOC at APL. When the simulation calculates the spacecraft are in contact with a satellite station (located across the globe, including APL's 60-foot dish antenna), the MOC sends those commands to RBSP. The instruments then send simulated data back to the MOC during later contacts, and the APL team makes the data available to the science instrument teams for their continued processing. "We have two people working each spacecraft during every contact," Harvey says. "We need to get 5.9 gigabytes (GB) of data down from each spacecraft each day" – during an RBSP-to-Earth contact period of about 3.5 hours – "but we're trying to get 6.3 GB for additional housekeeping data and to account for possible ground station outages." For comparison, most common DVDs hold about 4.7 GB.

A design concept known as "decoupling" helps both the mission operations team and the science instrument teams do their jobs at the same time without interfering with one another. The science instrument systems are designed to run independently (decoupled) from basic spacecraft systems such as communications and propulsion. The science instrument teams can run all of their simulation tests on their own without worries of conflicting needs for spacecraft resources with the mission simulation team.

Tough Tests
The spacecraft themselves are undergoing significant simulated tests during this 10-day stretch. "We picked this period in 2013 to test, in part, because it's a difficult period for spacecraft operation," Harvey says. "They're at maximum eclipse, meaning they won't see a lot of sunlight to power the spacecraft; they'll be lapping one another; and then we're going to do a precession maneuver to re-orient the spacecraft at the sun to maximize the power gathered by the solar panels. We're also going to perform a collision avoidance [COLA] maneuver. We'll be performing that with a team from NASA's Goddard Space Flight Center; they're the folks who keep track of our orbit and let us know about any possible encounter with another object up there."

The team will also perform a test that will verify that the spacecraft's Hardware Command Loss Timer (HWCLT) works; this device is a safety valve that shuts down critical spacecraft systems if it doesn't receive a specific command from the RBSP ground team after a certain period of time. Once the spacecraft shuts down the majority of its systems, the RBSP team will then attempt to recover it from the shutdown. "We just finished a 10-day simulation on our RBSP simulator," Harvey says, "and we learned a lot about the recovery that we'll be using in this real mission simulation. Models are good, but we really like to test the flight units. That's where we learn the most."

Creating and revealing challenges and issues – and overcoming them – is the real goal of these simulations. "We thought we'd do the simulation at the hardest point in the mission to prove out as much as possible," says Harvey. "We'll judge our success by how much we learn, and we learn much more from identifying problems and fixing them than if everything runs perfectly smooth. With this 10-day test, if something goes wrong on day two, we want to have it fixed for day three to see if it works."



While the RBSP 10-day mission simulation is being run from APL's mission operations center (MOC), engineers located near the thermal vacuum testing chambers monitor data and the twin spacecraft themselves, making sure that the testing is proceeding as designed and that RBSP is safe and secure.

http://rbsp.jhuapl.edu/newscenter/newsArticles/20120319.php

[instml]

Похожая миссия Demonstration and Science Experiments (DSX)

Space Environment Testbeds Overview

The Space Environment Testbeds (SET) Project performs flight and data investigations to address the Living With a Star (LWS) Program goal of understanding how the Sun/Earth interactions affect humanity. It is the part of the LWS program of Science Missions and Targeted Research and Technology (TR&T) ground-based investigations that respond to the following questions:

    * How and why does the Sun vary?
    * How do the Earth and planets respond?
    * What are the affects on humanity?

SET uses existing data and new data from the low-cost SET mission to achieve the following:

    * Define the mechanisms for space environment effects
    * Reduce uncertainties in the environment and its effects on spacecraft and their payloads
    * Improve design and operations guidelines and test protocols so that spacecraft anomalies and failures due to environmental effects during operations are reduced.

Mission Status

Launch Date : October 2012
Mission Phase D: Design & Development



The SET payload, consisting of 4 board experiments and a space weather monitor, is now integrated with the payload module at
Kirtland Air Force Base, NM.



Depiction of the SET payload on the AFRL Demonstration and Science Experiments (DSX) spacecraft

http://lws-set.gsfc.nasa.gov/

Joint Air Force-NASA Mission To Study High-radiation Orbits
18 April, 2011

WASHINGTON — The U.S. Air Force and NASA are on track to launch a joint satellite mission next year to study how radiation affects space hardware in some of the most rarely used and unpredictable Earth orbits.

    The results of the Demonstration and Science Experiments (DSX) mission could open up potentially valuable medium Earth orbits for communications and surveillance satellites and enable the development of satellite components that are less prone to damage from radiation, program officials said.

    The $155 million DSX mission, like NASA's pioneering Lunar Crater Observation and Sensing Satellite mission that deliberately slammed into the Moon in 2009, will use a standardized Atlas 5 payload adapter ring as a free-flying spacecraft.

    The DSX spacecraft, outfitted with three main scientific payloads, will be placed into a highly elliptical retrograde orbit that takes it 12,000 kilometers from Earth at apogee and 6,000 kilometers at perigee.

    The DSX satellite was at one time planned for launch in 2008, but it has had a hard time finding a ride to space because of its relatively low priority as a research and development mission and the fact that it is headed for an uncommon orbit, said Mark Scherbarth, program manager at the Space Vehicles Directorate at Kirtland Air Force Base, N.M. The satellite finally found a launch opportunity as a secondary payload on the Air Force's Defense Meteorological Satellite Program-19 mission scheduled for launch in October 2012. An Atlas 5 rocket will lift off from Vandenberg Air Force Base, Calif., and drop off the operational weather satellite in low Earth orbit before carrying DSX to a higher altitude.

    The launch should have DSX on orbit just in time to study the space environment during solar maximum, when the sun is most active and spacecraft are most vulnerable, Scherbarth said in a March 14 interview. The sun's current 11-year cycle is predicted to peak between November 2012 and May 2013.

    The satellite's unique orbit is designed to allow it to study the inner and outer Van Allen radiation belts, which can wreak havoc on spacecraft, Scherbarth said. The Van Allen belts are areas where high concentrations of ionized particles exist due to the Earth's magnetic field. The inner belt extends from roughly 6,700 kilometers to 9,600 kilometers above the equator, and the outer belt is roughly 19,100 kilometers to 63,700 kilometers above the equator; both belts curve closer to the Earth at the poles.

    "It's a very high-radiation environment, and radiation has a lot of detrimental effects not only on structural materials and thermal materials, but probably most importantly on the electronics in spacecraft, which have only increased over time," Scherbarth said.

    The two Air Force payloads, the Wave Particle Interaction Experiment and Space Weather Experiment, will collect data on the electron and proton populations in the regions. This information will be used to create better analytical models for designing spacecraft to operate in medium Earth orbits, Scherbarth said.

    "The analytical models that we have don't predict it very well," he said. "So you don't know what to expect up there. If you design your spacecraft a certain way and you guess wrong, you have either under-shielded and you die very quickly, or you've put way too much shielding, which is very expensive."

    Of the nearly 1,000 operating satellites currently orbiting the planet, 90 percent are either in low Earth orbits or 36,000 kilometers above the equator in the geosynchronous orbits favored by commercial communications satellites, according to the Union of Concerned Scientists' satellite database. Medium Earth orbit — the sparsely populated region above 2,000 kilometers but below 36,000 — is home to only about 6 percent of operating satellites, including the U.S. GPS and Russian Glonass navigation satellites (20,200 and 19,100 kilometers, respectively).

    The Air Force believes the region between the inner and outer Van Allen belts at around 10,000 kilometers has great promise. Satellites orbiting in the so-called slot region could enable communications about eight times faster than geosynchronous satellites and view the entire Earth with fewer satellites than needed in low Earth orbits, according to an Air Force fact sheet.

    NASA's contribution to the DSX mission is the Space Environment Testbeds (SET) payload designed to study space weather effects on spacecraft.

    Satellites rely on microelectronics that have become smaller and smaller over the years. While this has enabled them to be faster and more efficient and to process more data, it also has made them more vulnerable to radiation effects, said Dana Brewer, program executive for NASA's Living With a Star program.

    "The microelectronics change every two years," Brewer said in a March 16 interview. "As we go to smaller feature size, which is the gap between two junctions in a device, the smaller we go, the more damage we can produce from either an electron or a heavy ion in space."

    This problem is compounded by the fact that U.S. spacecraft are increasingly reliant on components derived from commercial hardware, Brewer said.

    "The government used to drive the electronics market, and now it's driven by commercial requirements," she said. "So we used to have radiation-hardened manufacturing sites, and with the big gaps in the devices, we didn't have as much of a problem.

    "We used to keep track of exactly how things were manufactured every step of the way, and a manufacturer couldn't change anything unless we knew about it. Now because we're doing more commercial, changes can occur in the manufacturing ... and that can affect their performance in space."

    The SET payload will use multiple dosimeters to detect radiation at different parts of the spacecraft. It also features experiments that will study the physics of how certain types of components degrade due to different types of radiation.

http://spacenews.com/military/110418-af-nasa-study-high-radiation-orbits.html

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RBSP Completes Thermal Vacuum Testing
April 3, 2012

The two thermal vacuum chambers at APL where the RBSP spacecraft have spent the past six weeks undergoing extreme heat and cold tests. These tests, performed in vacuum, mimic the harsh space environment above Earth in which RBSP will operate, following their scheduled launch in August 2012. Credit: JHU/APL

NASA's Radiation Belt Storm Probes have completed their thermal vacuum testing today, Tuesday April 3, one day earlier than planned. Thermal vacuum testing, which includes the cycling of temperatures between extremes of hot and cold, represents the culmination of the several severe tests that the spacecraft engineers use to assure that the spacecraft can survive the rigors of outer space. The early conclusion comes thanks to the efficient testing procedures and adroit time management of the RBSP team at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., where the twin spacecraft are being built and from where they will be operated following launch in August 2012.

"The thermal cycling testing proceeded nominally with very few issues encountered," says Bruce Williams, thermal lead engineer for the RBSP mission. "All spacecraft system and instruments, and test support hardware and software, performed as expected throughout the 30 day long test. The RBSP team should be very proud of this significant accomplishment."

The spacecraft are scheduled to be lowered from their test chambers today, and will then undergo several days of inspection and preparation for further testing prior to being shipped to the Kennedy Space Center in Florida on May 1.  

http://rbsp.jhuapl.edu/newscenter/newsArticles/20120403.php

[instml]

Похожая миссия Demonstration and Science Experiments (DSX)

Space Environment Testbeds Overview

The Space Environment Testbeds (SET) Project performs flight and data investigations to address the Living With a Star (LWS) Program goal of understanding how the Sun/Earth interactions affect humanity. It is the part of the LWS program of Science Missions and Targeted Research and Technology (TR&T) ground-based investigations that respond to the following questions:

    * How and why does the Sun vary?
    * How do the Earth and planets respond?
    * What are the affects on humanity?

SET uses existing data and new data from the low-cost SET mission to achieve the following:

    * Define the mechanisms for space environment effects
    * Reduce uncertainties in the environment and its effects on spacecraft and their payloads
    * Improve design and operations guidelines and test protocols so that spacecraft anomalies and failures due to environmental effects during operations are reduced.

Mission Status

Launch Date : October 2012
Mission Phase D: Design & Development

Запуск перенесен минимум на год из-за модернизации основного спутника DMSP F19.

[Salo]

http://www.spaceflightnow.com/tracking/index.html

Aug. 23     Atlas 5  •  RBSP
Launch window: 0807-0827 GMT (4:07-4:27 a.m. EDT)[/size]

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April 25, 2012

New launch date for RBSP

In this photo from mid-April following the completion of thermal vacuum testing, RBSP spacecraft B is lowered onto a stand, where it was prepared for shipment to the Kennedy Space Center, scheduled for May 1. Spacecraft A, already in its stand, is visible to the left of and behind spacecraft B. Credit: JHU/APL.

As NASA's twin Radiation Belt Storm Probe spacecraft prepare to leave the Johns Hopkins University Applied Physics Laboratory in Laurel, Md. and journey approximately 750 miles south to the Kennedy Space Center in Florida, a new launch date has been announced.

Launch is now scheduled for no earlier than Thursday, August 23, 2012, at approximately 4:00 a.m. EDT. The two RBSP spacecraft will be mated and placed aboard a ULA Atlas V 401 rocket and launched from Cape Canaveral Air Force Station into their orbits around Earth, where they will begin observations following a 60-day commissioning period.

During RBSP's two year primary mission, the spacecraft will allow scientists to study the Van Allen radiation belts which surround our planet, and learn more about the processes that create them and cause them to vary in size and intensity.

http://rbsp.jhuapl.edu/newscenter/intheloop/2012_0425.php

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April 26, 2012

In The Loop: Getting Ready For Kennedy

NASA's twin RBSP spacecraft are getting ready for the voyage from the Johns Hopkins Applied Physics Laboratory to the Kennedy Space Center, scheduled for May 1.



Both spacecraft are shown in the bases of their individual custom-built shipping containers; spacecraft B has been sealed in protective bagging. Credit: JHU/APL







RBSP team members are shown carefully guiding the top of spacecraft B's container onto the base using three guidance poles, which also help ensure the container is properly sealed for transport. After arrival in Florida, the spacecrafts' systems and instruments will be re-integrated and re-tested before a scheduled launch on August 23, 2012. Credit: JHU/APL

http://rbsp.jhuapl.edu/newscenter/intheloop/2012_0426.php

[Salo]

http://www.spaceflightnow.com/atlas/av032/120501rbsparrival/

Radiation Belt Storm Probes arrive at Florida launch site[/size]
BY STEPHEN CLARK
SPACEFLIGHT NOW
Posted: May 1, 2012

Twin NASA satellites designed to probe and predict changes in Earth's radiation belts arrived at the Kennedy Space Center on Tuesday, ready to begin several months of testing and assembly before lifting off on an Atlas 5 rocket in August.


Artist's concept of the Radiation Belt Storm Probes in orbit. Credit: NASA/JHUAPL
 
Riding inside a U.S. military cargo plane from Maryland, the twin spacecraft touched down at the spaceport's runway at 7:54 a.m. EDT (1154 GMT) Tuesday, according to George Diller, a NASA spokesperson.

Built at Johns Hopkins University's Applied Physics Laboratory in Laurel, Md., the satellites will investigate what causes the donut-shaped radiation belts surrounding Earth to expand and contract as solar storms erupt and propagate through space.

The Radiation Belt Storm Probes are due for launch Aug. 23 aboard a United Launch Alliance Atlas 5 rocket. The $530 million mission is scheduled to last at least two years.

Between now and launch, engineers will install solar panels on each satellite, test each spacecraft's systems, fill their tanks with propellant and encapsule the eight-sided vehicles inside the Atlas payload fairing. The satellites will be prepared for launch at the commercial Astrotech processing facility near KSC.

The spacecraft will fly through the inner and outer Van Allen radiation belts, named for their discoverer, James Van Allen, who was lead scientist for the first U.S. satellite to reach orbit - Explorer 1.

"It's important to us here on Earth because the radiation belts are home to a whole host of satellites that we rely upon," said Nicky Fox, RBSP's deputy project scientist at APL. "Geosynchronous orbit, for example, lies within the radiation belts. You actually have these space weather events that do cause the radiation belts to get bigger and hotter, and it can cause anomalies on spacecraft. The same processes at work in the radiation belts are also causing related space weather phenomena like the auroras, which is going to cause currents to flow down to the ground. That can cause problems for power grids, and it can affect the ionosphere's ability to reflect radio signals."

Despite their discovery in the 1950s, the radiation belts are not well understood by scientists. Physicists learned in the 1990s the belts are not as stable as once thought. Instead, they expand, heat up, and contract when charged particles from solar eruptions reach Earth.

"You can have three large coronal mass ejections from the sun looking like they're identical," Fox said. "One can cause the radiation belts to pump up, get very hot and very big. Another can actually have no real effect on them at all. And another can make them get smaller and less energetic, and yet if you were looking at just the solar signatures, you could think the three phenomena were the same."


Artist's concept of the Radiation Belt Storm Probes with a visualization of the radiation belts. Credit: NASA/JHUAPL
 

Not only will RBSP try to uncover why the belts respond differently to each solar storm, but data collected by the satellites could lead to predictions of when radiation fluxes will grow around Earth, giving satellite operators and astronauts warning before potential danger arrives.

The Atlas 5 rocket will inject the satellites into a highly elliptical equatorial orbit. The craft will later adjust their trajectories to enter slightly different orbits stretching from 375 miles high to an altitude of nearly 19,000 miles.

"We have two spacecraft heading up to the radiation belts," Fox said. "They are going to cut through both the inner belt and outer belt, so they will be looking at all the particle populations trapped there. The inner belt is primarily high-energy protons, [and it's] considered to be relatively stable. The outer belt is extremely dynamic, mostly made of electrons, and it changes dramatically in response to the weather coming toward us from the sun."

Full science operations will begin about two months after launch.

Two satellite are necessary to sample the radiation belts simultaneously from different locations. The tandem mission also allows the satellites to pass through stormy regions of space weather more often.

"If you only have one spacecraft, it would pass through a feature, and you would have to wait nine hours to come through it again, and you wouldn't really know if it had changed in time or if it changed in space," Fox said. "By having the two spacecraft come through relatively close together, you can actually start to distinguish those two phenomena."

Each satellite carries an identical suite of magnetometers, plasma and particle detectors, and electric field sensors.[/size]

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NASA's Radiation Belt Storm Probes Arrive at Kennedy Space Center

Twin RBSP Spacecraft Will Begin Exploration of Space Weather this Summer

NASA's twin Radiation Belt Storm Probe spacecraft are shown here in their protective shipping containers as they are unloaded from a United States Air Force C-17 at Kennedy Space Center, Fla. on the morning of May 1, 2012. RBSP is scheduled to begin its mission of exploration of Earth's Van Allen Radiation Belts and the extremes of space weather after launch, scheduled for August 23, 2012. Credit: JHU/APL

NASA's twin Radiation Belt Storm Probes (RBSP) safely arrived today at 7:54 a.m. EDT at the Kennedy Space Center, Fla., where they are scheduled for an August launch to begin their mission to study the extremes of space weather.

Just after 10:30 p.m. EDT on Monday, April 30, the RBSP spacecraft departed the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., where they were built for NASA, packed in custom-made shipping containers. They arrived at Andrews Air Force Base, where a United States Air Force C-17 cargo plane waited to transport them to Kennedy on May 1 for the start of launch processing.

Over the next several weeks, engineers and scientists from APL will prepare RBSP for launch in Florida. Other team members will continue to test the spacecraft's ' key operating systems remotely from the RBSP Mission Operations Center at APL.

For the past six months, teams of engineers and scientists have been putting the RBSP spacecraft through rigorous temperature, vibration, and stress testing designed to ensure they will operate flawlessly during and after launch.

RBSP will begin its exploration of Earth's Van Allen Radiation Belts with a predawn launch scheduled for Aug. 23, aboard a United Launch Alliance Atlas V 401 rocket. Each RBSP spacecraft weighs approximately 660 kilograms (1,455 pounds), and carries an identical set of five instrument suites that will allow scientists to unlock the mysteries of the radiation belts that surround our planet. The two spacecraft will fly in nearly identical, eccentric orbits that cover the entire radiation belt region, lapping each other several times over the course of the two-year mission. This will give researchers an unparalleled view into the mechanics and processes that change the size and intensity of the radiation belts over time. RBSP will explore space weather – changes in Earth's space environment caused by changes in the sun's energy flow – and especially its extreme conditions, which can disable satellites, cause power grid failures and disrupt GPS services.

The RBSP mission is part of NASA's Living With a Star program, which is managed by Goddard Space Flight Center in Greenbelt, Md. APL built the RBSP spacecraft and will manage the mission for NASA. More information on RBSP is available at http://rbsp.jhuapl.edu/ and http://www.nasa.gov/rbsp .

http://rbsp.jhuapl.edu/newscenter/newsArticles/20120501.php