samedi 3 janvier 2015

Russian cosmonaut and doctor Boris Morukov dies after car park mission to Mars












ROSCOSMOS logo.

January 3, 2015

Boris Morukov, a Russian cosmonaut and doctor who led an extraordinary experiment in which volunteers simulated a flight to Mars while never leaving a Moscow car park, has died at 64.

"We announce with grief that Boris Morukov died suddenly on New Year's Eve," Moscow's Institute of Biomedical Problems, where Morukov was deputy director, said on its website on Friday.

Morukov, a doctor and a former cosmonaut, was project director of the unprecedented Mars-500 simulation, in which an international team of six men spent 520 days in isolation to simulate a flight to Mars.

The experiment, which began in 2010 and ended in 2011, was organised jointly with the European Space Agency and the Institute of Biomedical Problems.

The experiment simulated the duration and isolation of a return journey to the Red Planet, even including "walks" on a sandpit replicating the Martian surface and 20-minute time gaps in communication with outside.

Cosmonaut Boris Morukov

The international team of one Chinese, one Italian, one Frenchman and three Russians spent the entire period in a 180-square-metre wood-lined complex in the carpark of the Moscow institute.

"Everything that we got out of this, both the positive and perhaps the negative, undoubtedly can be used in planning a real Mars flight," Morukov said after the experiment ended.

Morukov earlier led a series of experiments into the effects of long-term weightlessness on the human body.

In the most extreme experiment that started in 1986, a group of eight men spent 370 days lying in tilted beds to study the effect on their bone mass.

Born in Moscow, Morukov studied to become a doctor before undergoing training to become a specialist in space medicine. He also trained as a cosmonaut at the Gagarin training centre.

In 2000, he was a crew member on a flight on the US Space Shuttle Atlantis to prepare the International Space Station for its first permanent crew.

Morukov "will always remain in our hearts as a talented scientist, a brilliant organiser and a kind, helpful person", the Institute of Biomedical Problems said.

Biography and more information about the deceased Cosmonaut Boris Morukov, visit: http://en.wikipedia.org/wiki/Boris_Morukov

Image, Text, Credits: ROSCOSMOS/NASA/AFP.

R.I.P. 
Condolences, Orbiter.ch

Crew Aboard Station Prepares for Arrival of Dragon










ISS - Expedition 42 Mission patch.

January 3, 2015

Happy New Year 16 Times on Space Station!

The Expedition 42 crew orbiting Earth on the International Space Station gets the opportunity to celebrate New Year’s Eve a whopping 16 times as it circles the globe at 17,500 miles an hour.

Commander Barry “Butch” Wilmore and his crew, which includes NASA’s Terry Virts, Russian cosmonauts Elena Serova, Alexander Samoukutyaev and Anton Shkaplerov, and European Space Agency astronaut Samantha Cristoforetti, say they plan to celebrate with fruit juice toasts. The year 2015 starts officially for the station crew at 7 p.m. EST Jan. 31, which is midnight by the Universal Time Clock (UTC), also known as Greenwich Mean Time (GMT), in London. The crew is scheduled to be in its sleep shift, but may elect to stay up late since it has a day off planned for New Year’s Day.

Watch the Happy New Year message: https://www.youtube.com/watch?v=VXvYcIbFVzs&list=PLiuUQ9asub3Qq1AQRirDI-naOwo1H5gaB&index=1


Image above: Terry Virts (@AstroTerry) tweets: Unwrapping an early Christmas gift last week: @AstroRobonaut is my favorite action figure.

The crew spent New Year’s Eve day working on a variety of experiments, ranging from those directed at better understanding changes that occur in the human eye during long-duration spaceflights, and with Earth observations aimed at helping with disaster aid on the Earth’s surface.

Read more about the Ocular Health experiment: http://www.nasa.gov/mission_pages/station/research/experiments/204.html

Read more about the ISS SERVIR Environmental Research and Visualization System (ISERV): http://www.nasa.gov/mission_pages/station/research/experiments/867.html

The crew also continued preparations for the arrival of the next cargo supply ship, the commercial resupply mission of SpaceX-5 and the Dragon spacecraft. Launch of Dragon on a Space-X Falcon 9 booster is planned for 6:20 a.m. EST Tuesday, Jan. 6, 2015. NASA Television launch coverage begins at 5 a.m.

Dragon will rendezvous with the space station Thursday, Jan. 8, and Wilmore will use the 58-foot robotic arm to grab the Dragon by its tail and berth if to the station. Grapple is expected about 6 a.m. NASA Television coverage of the grapple starts at 4:30 a.m. Thursday, and installation coverage will begin at 8:15 a.m. Dragon is loaded with more than 3,700 pounds of scientific experiments, technology demonstrations and supplies, including critical materials to support 256 science and research investigations that will take place on the space station during ISS Expeditions 42 and 43.

SpaceX Dragon cargo

A series of briefings outlining Dragon’s mission and the scientific research it will be carrying is planned Monday, Jan. 5.

Read full schedule of SpaceX-5 and ISS Research briefings: http://www.nasa.gov/press/2014/december/nasa-updates-pre-launch-briefings-for-upcoming-resupply-mission-to-space-station/#.VKQns1q99W8

Watch Terry Virts’ #SpaceVine of Robonaut: https://t.co/kNtYDaJI2M

For more information about the International Space Station (ISS), visit: http://www.nasa.gov/mission_pages/station/main/index.html

Images, Text, Credit: NASA / NASA TV.

Greetings, Orbiter.ch

vendredi 2 janvier 2015

Solar Dynamics Observatory Welcomes the New Year












NASA - Solar Dynamics Observatory (SDO) patch.

January 2, 2015


There were no fireworks on the sun to welcome in the New Year and only a few C-class flares during the last day of 2014. Instead, the sun starts 2015 with an enormous coronal hole near the south pole. This image, captured on Jan. 1, 2015 by the Atmospheric Imaging Assembly (AIA) instrument on NASA's Solar Dynamics Observatory, shows the coronal hole as a dark region in the south.

Coronal holes are regions of the corona where the magnetic field reaches out into space rather than looping back down onto the surface. Particles moving along those magnetic fields can leave the sun rather than being trapped near the surface. Those trapped particles can heat up and glow, giving us the lovely AIA images. In the parts of the corona where the particles leave the sun, the glow is much dimmer and the coronal hole looks dark.

Coronal holes were first seen in images taken by astronauts on board NASA’s Skylab space station in 1973 and 1974. They can be seen for a long time, although the exact shape changes all the time. The polar coronal hole can remain visible for five years or longer. Each time a coronal hole rotates by the Earth we can measure the particles flowing out of the hole as a high-speed stream, another source of space weather.

Charged particles in the Earth’s radiation belts are accelerated when the high-speed stream runs into the Earth’s magnetosphere. The acceleration of particles in the magnetosphere is studied by NASA’s Van Allen Probes mission.

As Solar Cycle 24 fades, the number of flares each day will get smaller, but the coronal holes provide another source of space weather that needs to be understood and predicted.

For more information about Solar Dynamics Observatory (SDO), visit: http://www.nasa.gov/mission_pages/sdo/main/

Related links:

NASA’s Skylab space station in 1973 and 1974: http://solarscience.msfc.nasa.gov/Skylab.shtml

NASA’s Van Allen Probes mission: http://www.nasa.gov/mission_pages/rbsp/mission/

Image, Text, Credits: NASA/SDO/Caption: Dean Pesnell.

Cheers, Orbiter.ch

jeudi 1 janvier 2015

Technology Innovations Spin NASA's SMAP into Space











NASA - SMAP Mission logo.

January 1, 2015

SMAP: Mapping Global Soil Moisture, Managing a Better Future

Video above: Launching in January 2015, NASA's Soil Moisture Mapping satellite (SMAP) will track water in the soil. Data gathered with help forecast weather, floods, drought, crop yield and landslides - all from outer space. Video Credit: NASA Jet Propulsion Laboratory.

It's active. It's passive. And it's got a big, spinning lasso.

Scheduled for launch on Jan. 29, 2015, NASA's Soil Moisture Active Passive (SMAP) instrument will measure the moisture lodged in Earth's soils with an unprecedented accuracy and resolution. The instrument's three main parts are a radar, a radiometer and the largest rotating mesh antenna ever deployed in space.

Remote sensing instruments are called “active” when they emit their own signals and “passive” when they record signals that already exist. The mission's science instrument ropes together a sensor of each type to corral the highest-resolution, most accurate measurements ever made of soil moisture -- a tiny fraction of Earth's water that has a disproportionately large effect on weather and agriculture.

To enable the mission to meet its accuracy needs while covering the globe every three days or less, SMAP engineers at NASA's Jet Propulsion Laboratory in Pasadena, California, designed and built the largest rotating antenna that could be stowed into a space of only one foot by four feet (30 by 120 centimeters) for launch. The dish is 19.7 feet (6 meters) in diameter.

"We call it the spinning lasso," said Wendy Edelstein of NASA's Jet Propulsion Laboratory, Pasadena, California, the SMAP instrument manager. Like the cowboy's lariat, the antenna is attached on one side to an arm with a crook in its elbow. It spins around the arm at about 14 revolutions per minute (one complete rotation every four seconds). The antenna dish was provided by Northrop Grumman Astro Aerospace in Carpinteria, California. The motor that spins the antenna was provided by the Boeing Company in El Segundo, California.

"The antenna caused us a lot of angst, no doubt about it," Edelstein noted. Although the antenna must fit during launch into a space not much bigger than a tall kitchen trash can, it must unfold so precisely that the surface shape of the mesh is accurate within about an eighth of an inch (a few millimeters).

The mesh dish is edged with a ring of lightweight graphite supports that stretch apart like a baby gate when a single cable is pulled, drawing the mesh outward. "Making sure we don't have snags, that the mesh doesn't hang up on the supports and tear when it's deploying -- all of that requires very careful engineering," Edelstein said. "We test, and we test, and we test some more. We have a very stable and robust system now."

Artist's rendering of the SMAP instrument. Image Credit: NASA

SMAP's radar, developed and built at JPL, uses the antenna to transmit microwaves toward Earth and receive the signals that bounce back, called backscatter. The microwaves penetrate a few inches or more into the soil before they rebound. Changes in the electrical properties of the returning microwaves indicate changes in soil moisture, and also tell whether or not the soil is frozen. Using a complex technique called synthetic aperture radar processing, the radar can produce ultra-sharp images with a resolution of about half a mile to a mile and a half (one to three kilometers).

SMAP's radiometer detects differences in Earth's natural emissions of microwaves that are caused by water in soil. To address a problem that has seriously hampered earlier missions using this kind of instrument to study soil moisture, the radiometer designers at NASA's Goddard Space Flight Center, Greenbelt, Maryland, developed and built one of the most sophisticated signal-processing systems ever created for such a scientific instrument.

The problem is radio frequency interference. The microwave wavelengths that SMAP uses are officially reserved for scientific use, but signals at nearby wavelengths that are used for air traffic control, cell phones and other purposes spill over into SMAP's wavelengths unpredictably. Conventional signal processing averages data over a long time period, which means that even a short burst of interference skews the record for that whole period. The Goddard engineers devised a new way to delete only the small segments of actual interference, leaving much more of the observations untouched.

Combining the radar and radiometer signals allows scientists to take advantage of the strengths of both technologies while working around their weaknesses. "The radiometer provides more accurate soil moisture but a coarse resolution of about 40 kilometers [25 miles] across," said JPL's Eni Njoku, a research scientist with SMAP. "With the radar, you can create very high resolution, but it's less accurate. To get both an accurate and a high-resolution measurement, we process the two signals together."

SMAP will be the fifth NASA Earth science mission launched within the last 12 months.

For more about the SMAP mission, visit: http://www.nasa.gov/smap/

NASA monitors Earth's vital signs from space, air and land with a fleet of satellites and ambitious airborne and ground-based observation campaigns. NASA develops new ways to observe and study Earth's interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing. The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.

For more information about NASA's Earth science activities this year, visit: http://www.nasa.gov/earthrightnow

Image (mentioned), Video (mentioned), Text, Credits: NASA Earth Science News Team, written by Carol Rasmussen/JPL/Alan Buis.

Greetings, Orbiter.ch

CASC ends 2014 with Long March 3A launch of Fengyun-2G












CASC - China Aerospace Science and Technology Corporation logo.

January 1, 2015


Image above: A Long March 3A rocket launched at 01:02 GMT Wednesday (8:02 p.m. EST Tuesday) with the Fengyun 2G weather satellite. Image Credit: Xinhua.

CASC ends 2014 with Long March 3A launch of Fengyun-2G (Fengyun-2-8) geostationary meteorological satellite using a Long March 3A (Chang Zheng 3A) rocket. The launch took place at 01:02 UTC on Wednesday from Pad LC2 at the Xichang Satellite Launch Center.

China’s fleet of Fengyun 2 spacecraft have a similar mission to NOAA’s GOES weather satellites in geostationary orbit. They provide non-stop images of clouds and storm systems over a third of the planet from the Middle East to the Central Pacific Ocean.

Fengyun 2G geostationary weather satellite. Image Credit:CASC

Chinese meteorologists exchange weather data acquired by the Fengyun satellites with NOAA and Eumetsat, its European counterpart.

One more satellite from the fleet is scheduled before the new Fengyun-4 satellites enters service, with the first launch of the next generation scheduled for December 2015.

Made by China Aerospace Science and Technology Corp. (CASC), Fengyun 2G is expected to operate at least four years, but previous Chinese weather satellites have functioned longer than designed. The new satellite features several technical improvements, and officials expect it to work until 2020, the China Meteorological Administration said on its website.

The barrel-shaped satellite is spin-stabilized — rotating at 100 rpm — and carries a scanning radiometer to observe Earth’s weather in visible and infrared wavelengths, allowing day and night imagery of storms.

For more information about China Aerospace Science and Technology Corporation (CASC), visit: http://english.spacechina.com/n16421/index.html

Images (mentioned), Text, Credits: CASC/Orbiter.ch Aerospace.

Happy New Year 2015! Best regards, Orbiter.ch

mercredi 31 décembre 2014

Happy New Year 2015!


 December 31, 2014

Orbiter.ch Space News wishes you a Happy New Year 2015 to all our readers and subscribers. Thank you for your interest and support for astronomy, aerospace, technology and science!

2015 will be another year of discovery's and exploration of our cosmos.

Since opening in 2010, this blog is funded by three sources of income:

- The advertising broadcast by Google Adsense (banner at the bottom of page)
- The company Orbiter.ch Aerospace (65% of funding)
- A government grant (Sfr 3600.- per year)

The public subsidy was removed (savings measures of government).

2015 will be a year of change for this blog, advertising will be visible on the lateral margins. In order to continue to inform and educate free, this blog needs money to continue. For information about hosting advertisements on this blog, contact: orbiter@live.fr


Best wishes for 2015, Orbiter.ch

Hubble Sees an Ancient Globular Cluster











NASA - Hubble Space Telescope patch.

December 31, 2014


This image captures the stunning NGC 6535, a globular cluster 22,000 light-years away in the constellation of Serpens (The Serpent) that measures one light-year across.

Globular clusters are tightly bound groups of stars which orbit galaxies. The large mass in the rich stellar centre of the globular cluster pulls the stars inward to form a ball of stars. The word globulus, from which these clusters take their name, is Latin for small sphere.

Globular clusters are generally very ancient objects formed around the same time as their host galaxy. To date, no new star formation has been observed within a globular cluster, which explains the abundance of aging yellow stars in this image, most of them containing very few heavy elements.

Hubble and the sunrise over Earth

NGC 6535 was first discovered in 1852 by English astronomer John Russell Hind. The cluster would have appeared to Hind as a small, faint smudge through his telescope. Now, over 160 years later, instruments like the Advanced Camera for Surveys (ACS) and Wide Field Camera 3 (WFC3) on the NASA/ European Space Agency (ESA) Hubble Space Telescope allow us to marvel at the cluster and its contents in greater detail.

For more information and images from Hubble Space Telescope, visit: http://hubblesite.org/ and http://www.spacetelescope.org/

Images, Video, Text, Credits: ESA/Hubble & NASA, Acknowledgement: Gilles Chapdelaine.

Happy New Year, best regards, Orbiter.ch

mardi 30 décembre 2014

Crew Shares New Year’s Wishes, Research Continues










ISS - Expeditiom 42 Mission patch.

December 30, 2014


Image above: Expedition 42 Commander Barry Wilmore and Flight Engineer Samantha Cristoforetti answer questions posed by CBS and BBC reporters on Dec. 30, 2014. Image Credit: NASA TV.

As the crew of the International Space Station prepares to ring in the new year with a fruit juice toast, NASA today released a pre-recorded  New Year’s greeting from space for everyone on Earth.

Happy New Year from the International Space Station

Expedition 42 Commander Barry “Butch” Wilmore  of NASA and Flight Engineer Samantha Cristoforetti of the European Space Agency shared their plans for a New Year’s Eve celebration and some resolutions during an interview with CBS News and the BBC.

Watch the Dec. 30 interview: https://www.youtube.com/playlist?list=PL2aBZuCeDwlQMQj1uPER7lrbkZY7qcUN3

The crew spent most of its day conducting a variety of experiments, ranging from human life sciences to physics and Earth observations, and threw in a good measure of routine maintenance on station systems.

Cristoforetti set up hardware for eye exams using ocular coherence tomography, which records a detailed 3-D image of the retina and the interior of the eyes, so doctors may look to better understand why some astronauts return to Earth with long-term vision problems. Wilmore then conducted the tests on both Cristoforetti and NASA Flight Engineer Terry Virts.

Read more about the Ocular Health experiment: http://www.nasa.gov/mission_pages/station/research/experiments/204.html

Wilmore also continued work setting up and conducting experiment runs with the European Space Agency Haptics-1 experiment, using a body-mounted force-feedback joystick and a tablet computer to help scientists learn how people in weightlessness might use such game-like hardware to someday control robots on another planet, moon or asteroid from an orbiting human spacecraft.

Read more about the Haptics-1 experiment: http://www.nasa.gov/mission_pages/station/research/experiments/1720.html

Russian cosmonauts Elena Serova, Alexander Samoukutyaev and Anton Shkaplerov spent their day performing station life support system maintenance, testing a procedure for detecting air leaks on the station and conducting a Russian physics experiment on the dynamics of charged particles in space.

International Space Station (ISS) sunrise

This entry was posted in Expedition 42, Uncategorized and tagged alexander samoukutyaev, anton shkaplerov, barry wilmore, BBC, CBS, elena serova, eye, haptics, health, interview, new year's, ocular, samantha cristoforetti, terry virts on December 30, 2014 by khumphries.

For more information about the International Space Station (ISS), visit: http://www.nasa.gov/mission_pages/station/main/index.html

Images, Video, Text, Credit: NASA / NASA TV.

 HAPPY NEW YEAR!!!

Greetings, Orbiter.ch

Dawn Spacecraft Begins Approach to Dwarf Planet Ceres












NASA - Dawn Mission patch.

December 30, 2014

Crazy Engineering: Ion Propulsion and the Dawn Mission

Video above: Ion propulsion isn’t something found only in science fiction. Ion engines are a real deal and drive NASA's Dawn spacecraft, en route to dwarf planet Ceres. Big things do come in small packages. Video Credit: NASA Jet Propulsion Laboratory.

- Dawn has entered its approach phase toward Ceres
- The spacecraft will arrive at Ceres on March 6, 2015

NASA's Dawn spacecraft has entered an approach phase in which it will continue to close in on Ceres, a Texas-sized dwarf planet never before visited by a spacecraft. Dawn launched in 2007 and is scheduled to enter Ceres orbit in March 2015.

Dawn recently emerged from solar conjunction, in which the spacecraft is on the opposite side of the sun, limiting communication with antennas on Earth. Now that Dawn can reliably communicate with Earth again, mission controllers have programmed the maneuvers necessary for the next stage of the rendezvous, which they label the Ceres approach phase. Dawn is currently 400,000 miles (640,000 kilometers) from Ceres, approaching it at around 450 miles per hour (725 kilometers per hour).

The spacecraft's arrival at Ceres will mark the first time that a spacecraft has ever orbited two solar system targets. Dawn previously explored the protoplanet Vesta for 14 months, from 2011 to 2012, capturing detailed images and data about that body.

"Ceres is almost a complete mystery to us," said Christopher Russell, principal investigator for the Dawn mission, based at the University of California, Los Angeles. "Ceres, unlike Vesta, has no meteorites linked to it to help reveal its secrets. All we can predict with confidence is that we will be surprised."

The two planetary bodies are thought to be different in a few important ways. Ceres may have formed later than Vesta, and with a cooler interior. Current evidence suggests that Vesta only retained a small amount of water because it formed earlier, when radioactive material was more abundant, which would have produced more heat. Ceres, in contrast, has a thick ice mantle and may even have an ocean beneath its icy crust.

Ceres, with an average diameter of 590 miles (950 kilometers), is also the largest body in the asteroid belt, the strip of solar system real estate between Mars and Jupiter. By comparison, Vesta has an average diameter of 326 miles (525 kilometers), and is the second most massive body in the belt.


Image above: This artist's concept shows NASA's Dawn spacecraft heading toward the dwarf planet Ceres. Image Credit: NASA/JPL-Caltech.

The spacecraft uses ion propulsion to traverse space far more efficiently than if it used chemical propulsion. In an ion propulsion engine, an electrical charge is applied to xenon gas, and charged metal grids accelerate the xenon particles out of the thruster. These particles push back on the thruster as they exit, creating a reaction force that propels the spacecraft. Dawn has now completed five years of accumulated thrust time, far more than any other spacecraft.

"Orbiting both Vesta and Ceres would be truly impossible with conventional propulsion. Thanks to ion propulsion, we're about to make history as the first spaceship ever to orbit two unexplored alien worlds," said Marc Rayman, Dawn's chief engineer and mission director, based at NASA's Jet Propulsion Laboratory in Pasadena, California.

The next couple of months promise continually improving views of Ceres, prior to Dawn's arrival. By the end of January, the spacecraft's images and other data will be the best ever taken of the dwarf planet.

The Dawn mission to Vesta and Ceres is managed by JPL, a division of the California Institute of Technology in Pasadena, for NASA's Science Mission Directorate, Washington. UCLA is responsible for overall Dawn mission science.

More information about Dawn: http://dawn.jpl.nasa.gov

Image (mentioned), Video (mentioned), Text, Credits: NASA/JPL/Elizabeth Landau.

Best regards, Orbiter.ch

lundi 29 décembre 2014

A Solar Wind Workhorse Marks 20 Years of Science Discoveries












NASA - Wind Mission patch.

December 29, 2014

The end of 2014 marks two decades of data from a NASA mission called Wind. Wind -- along with 17 other missions – is part of what's called the Heliophysics Systems Observatory, a fleet of spacecraft dedicated to understanding how the sun and its giant explosions affect Earth, the planets and beyond.

Wind launched on Nov. 1, 1994, with the goal of characterizing the constant stream of particles from the sun called the solar wind. With particle observations once every 3 seconds, and 11 magnetic measurements every second, Wind measurements were – and still are – the highest cadence solar wind observations for any near-Earth spacecraft.


Image above: The Wind spacecraft has spent much of its 20 years in space out in front of the magnetic fields – the magnetosphere – that surrounds Earth, observing the constant stream of particles flowing by from the solar wind. Image Credit: NASA.

During its more than 20 years in space, Wind has taken up position at various spots around our planet to help determine how near-Earth space interacts with incoming energy and particles from the sun. Assessing the complex variations of the charged particles making up the solar wind cannot be done from a single point in space. That would be like trying to understand the entire Earth's weather system from a single collection station in Washington, D.C. So, Wind was part of a game changing idea: launch several missions to work in tandem to understand how the dynamic magnetosphere surrounding Earth reacts to the sun. Sitting at a point between Earth and the sun, Wind was the vanguard, observing the solar wind.

"We had a fairly simple original objective," said Adam Szabo, the project scientist for Wind at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "The number one question was to find out how the solar wind was driving changes in the magnetosphere."

The original flotilla, named the Global Geospace Science (GGS) campaign, was composed of the Polar spacecraft observing Earth’s magnetosphere in high latitudes, Equator-S making equatorial magnetospheric measurements, and the Japanese Geotail patrolling the elongated magnetotail  -- the long ribbon of magnetosphere that trails behind Earth, away from the sun. The original GGS program was rapidly extended with additional missions to form the International Solar Terrestrial Program, or ISTP.

With its mandate to watch the frontlines, Wind was sent into orbit around what's called a Lagrangian point, a point that experiences balanced gravity from both the sun and Earth. Wind took up residence in an elliptical orbit around the first Langrangian point (L1), lying between Earth and the sun, some 932,000 miles away from Earth. While several satellites have since been in a similar orbit, Wind was only the second spacecraft ever to orbit L1.

In 1997, another solar wind monitor joined the L1 neighborhood. The Advanced Composition Explorer, or ACE, was designed both to measure properties of the incoming solar wind, and to give scientists advanced notice of larger, more intense eruptions from the sun, such as coronal mass ejections, or CMEs. At their worst, CMEs can compress the magnetosphere so severely that satellites suddenly find themselves outside that protective bubble, exposed to harsh solar radiation. The compression can also set off vibrations in the magnetosphere that can induce electrical surges in power grids on Earth.

Graphic of Wind spacecraft. Image Credit: NASA

NASA decided to take advantage of having two spacecraft monitoring the solar wind by moving Wind to the second Lagrange point (L2), a point on the other side of Earth from the sun. L2 is some 1.1 million miles down the magnetotail, four times the distance to the moon. From this new location, Wind was able to provide measurements from deeper in the magnetotail than any other missions have done.

Working together, ACE and Wind unraveled even more mysteries about the solar wind, helping answer questions such as, did the observations on one side correlate to what was happening on the other? Did any particular occurrence stay coherent over long distances or did they change as they moved?

During this time frame, the ISTP missions helped scientists understand more about the size of events in the magnetosphere. At a distance of under 90,000 miles, what one satellite observed could be correlated to measurements from the other. That means that knowing what one satellite saw could perhaps be used to predict what might be seen elsewhere in the magnetosphere, as long as it was less than 90,000 miles away.  At greater distances, however, any given blast of energy or particles moving through the magnetosphere simply changed too much to be predictable.

From 2000-2003, Wind moved through a variety of positions, including off to the side of the magnetosphere, 1.5 million miles away from Earth, and a return trip to the magnetotail. In 2004, Wind was moved back to the L1 point permanently.

"In its position at L1, Wind has witnessed a handful of first ever sightings of different kinds of electromagnetic waves traveling by in the solar wind," said Lynn Wilson, deputy project scientist for Wind at Goddard. "In space where a particle could travel 100 million miles before hitting another one, these waves simply can't be working the same way sound or water waves do, pushing material along. It has opened up whole areas of research trying to understand these unexpected properties."

Wind continues to work with other spacecraft -- and is even looking to the future. In 2018, NASA will launch a new mission called Solar Probe Plus that will go to within 3.8 million miles of the sun to explore what happens within the solar wind near the sun. One big mystery is the question of what keeps the solar wind heated. One would think that the solar wind would cool down as it expands and travels away from the sun, but it remains hotter than expected. Some intrinsic activity within the wind must continue to generate heat. It is known that magnetic reconnection – a process in which magnetic energy is converted into heat and acceleration of particles – is part of the process. In sync with this endeavor, Wind has searched for the signatures of magnetic reconnection closer to home.

"The question we had was whether magnetic reconnection could ever happen in the low density solar wind, where things are not as dynamic as in the sun's atmosphere," said Szabo. "Wind found signatures of reconnection, but they weren't violent reactions like what happens closer to the sun. These were subtle, lower energy events, and the signature were thin streams of particles accelerating outward, which we call reconnection jets."

These jets last for such short periods of time that the 3-second data collection on Wind is just barely fast enough to capture them – an example of how Wind's high cadence measurements still shine 20 years after launch, and how its mission continues to offer important data for scientists.

Despite having a planned mission of five years, Wind was built with the hope of lasting much longer. Wind has enough fuel to keep it in orbit around L1 until 2074, and every effort has been made to reduce stress on its instruments in order to maintain their longevity. At 20 years, it is still going strong and helping scientists understand the forces that buffet near-Earth space.

Related Links:

More on Wind: http://science.nasa.gov/missions/wind/

Recent Science Results:

http://www.nasa.gov/mission_pages/sunearth/news/wind-slamswaves.html
http://www.nasa.gov/mission_pages/sunearth/news/riding-plasma-waves.html
http://science.nasa.gov/science-news/science-at-nasa/2013/08mar_solarwind/
http://www.nasa.gov/content/goddard/more-than-meets-the-eye-nasa-scientists-listen-to-data/index.html

Images (mentioned), Text, Credits: NASA's Goddard Space Flight Center/Karen C. Fox.

Greetings, Orbiter.ch