samedi 14 mars 2015

New NASA Mission to Study Ocean Color, Airborne Particles and Clouds

NASA logo.

March 14, 2015

NASA is beginning work on a new satellite mission that will extend critical climate measurements of Earth’s oceans and atmosphere and advance studies of the impact of environmental changes on ocean health, fisheries and the carbon cycle.

Tentatively scheduled to launch in 2022, the Pre-Aerosol Clouds and ocean Ecosystem (PACE) mission will study Earth’s aquatic ecology and chemistry, and address the uncertainty in our understanding of how clouds and small airborne particles called aerosols affect Earth’s climate. PACE will be managed by NASA's Goddard Space Flight Center in Greenbelt, Maryland.

“Knowing more about global phytoplankton community composition will help us understand how living marine resources respond to a changing climate,” said Jeremy Werdell, PACE project scientist at Goddard. “With PACE, we will learn more about the role of marine phytoplankton in the global carbon cycle.”

Image above: New measurements by NASA’s PACE spacecraft will advance our understanding of how living marine resources respond to a changing climate. NASA pioneered the field of global ocean color observations with the SeaWIFS satellite sensor from 1997 to 2010. Image Credit: NASA.

NASA has long used satellites to observe the global ocean’s microscopic algal communities, which play a significant role in the ocean’s ecology and the global carbon cycle. PACE will provide a global view of the planet's microscopic ocean algae called phytoplankton. Phytoplankton live in the sunlit upper layer of the ocean, producing at least half of the oxygen on Earth and form the base of the marine food chain.

Goddard will build PACE’s ocean color instrument. This PACE sensor will allow scientists to see the colors of the ocean, from the ultraviolet to near infrared, and obtain more accurate measurements of biological and chemical ocean properties, such as phytoplankton biomass and the composition of phytoplankton communities. These changes in the ocean’s color help identify harmful algal blooms.

Quantifying phytoplankton is essential for understanding the carbon cycle and tracking climate variability and change. The ocean absorbs atmospheric carbon dioxide into solution at the sea surface. Like land plants, phytoplankton use carbon dioxide to create their organic biomass via photosynthesis. Phytoplankton vary greatly in their size, function, and response to environmental and ecosystem changes or stresses such as ocean acidification.

Dissolved carbon dioxide also reacts with seawater and alters its acidity. About one fourth of human-made carbon dioxide ends up in the ocean.

"NASA Goddard pioneered ocean color remote sensing 35 years ago with the very first satellite observations, and the Center has been committed to supporting the science ever since," said Piers Sellers, deputy director of NASA Goddard Earth Science. "Goddard scientists play a critical role in generating and improving core satellite data sets for the international ocean biology community. We look forward to extending this important record into the future with PACE."

Pre-Aerosol Clouds and ocean Ecosystem (PACE) satellite. Image Credit: NASA

In addition to gathering data on ocean color, PACE will measure clouds and tiny airborne particles like dust, smoke and aerosols in the atmosphere to supplement measurements from existing NASA satellite missions. These measurements are critical for understanding the flow of natural and human made aerosols in the environment. Aerosols affect how energy moves in and out of Earth’s atmosphere directly by scattering sunlight, and indirectly by changing the composition of clouds. Aerosols also can affect the formation of precipitation in clouds and change rainfall patterns.

The blend of atmospheric and oceanic observations from PACE is critical as ocean biology is affected by aerosols deposited onto the ocean, which in turn, produce aerosol precursors that influence atmospheric composition and climate. NASA is currently planning a second PACE instrument, a polarimeter, to better measure aerosol and cloud properties. These measurements will improve understanding of the roles of aerosols in the climate system.

Goddard's proof-of-concept sensor for measuring ocean color — the Coastal Zone Color Scanner that flew on the Nimbus-7 satellite from 1978 to 1986 — was the first sensor to demonstrate phytoplankton biomass could be quantified from space. The Sea-Viewing Wide Field-of-View Sensor or SeaWiFS mission collected data from 1997 to 2010 and was the first mission dedicated to routinely observe ocean biology, chemistry, and ecology for long-term climate research. Currently, researchers employ the Moderate Resolution Imaging Spectroradiometer that flies aboard both NASA’s Terra and Aqua spacecraft, and the Visible Infrared Imager Radiometer Suite aboard the NASA-NOAA Suomi National Polar-orbiting Partnership satellite, to measure biological and chemical properties of the ocean, as well as aerosol and cloud properties.

NASA capped the costs for PACE at $805 million, to cover the spacecraft, mission design and engineering, science, instruments, launch vehicle, data processing, and operations.

For more information about PACE, visit:

NASA uses the vantage point of space to increase our understanding of our home planet, improve lives, and safeguard our future. NASA develops new ways to observe and study Earth's interconnected natural systems with long-term data records. The agency freely shares this unique knowledge and works with institutions around the world to gain new insights into how our planet is changing.

For more information on NASA’s Earth science activities, visit:

Images (mentioned), Text, Credits: NASA/Steve Cole/Goddard Space Flight Center/Rani Gran.


vendredi 13 mars 2015

CERN - The LHC: A stronger machine

CERN - European Organization for Nuclear Research logo.

13 March 2015

The LHC: A stronger machine

In early 2013, after three years of running, the Large Hadron Collider (LHC) shut down for planned maintenance. Hundreds of engineers and technicians spent about two years consolidating and strengthening the accelerator in preparation for running at the higher collision energy of 13 TeV, nearly double the collision energy of the LHC's first run. In the video above, CERN managers, engineers and operational staff describe this huge engineering effort.

Jean-Philippe Tock of the CERN Technology department led the Superconducting Magnets and Circuits Consolidation project during the shutdown. His team's focus was on consolidating more than 10,000 high-current splices in some 1695 interconnections between magnets in the LHC. Engineers Anna Chrul and Mirko Pojer describe work in the tunnel: the safety release valves for dispelling helium safely from the magnets; and the process of adding a shunt to each splice within the interconnection to provide an alternate pathway for the 11,000-amp current to safely pass from magnet to magnet in the event of a fault.

The Large Hadron Collider (LHC) at CERN

CERN Director for accelerators and technology, Frédérick Bordry, takes us through the implications of running the accelerator at the higher collision energy of 13 TeV, and mentions some of the requirements for the machine to reach this new energy frontier – such as radiation-resistant electronics and a high-quality vacuum.

Finally Katy Foraz, activities coordinator for LS1 (long shutdown 1), describes the logistical challenges of coordinating the maintenance work. As an example of the scale of the project, she tells us that over this two-year period the access lift to the LHC tunnel went up and down more than 400,000 times!

Overall view of the LHC experiments

Now teams are working hard for the upcoming restart. The first circulating beams of protons in the LHC are planned for the week beginning 23 March, and first 13 TeV collisions are expected in late May to early June.

For a full account of the work to make the LHC a stronger machine, check out the resources and infographics here:


CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.

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For more information about the European Organization for Nuclear Research (CERN), visit:

Image, Graphic, Video, Text, Credits: CERN/Cian O'Luanaigh.


Sixth Galileo satellite reaches corrected orbit

ESA - Galileo Navigation Satellites logo.

13 March 2015

The sixth Galileo satellite of Europe’s navigation system has now entered its corrected target orbit, which will allow detailed testing to assess the performance of its navigation payload.

Launched with the fifth Galileo last August, its initial elongated orbit saw it travelling as high as 25 900 km above Earth and down to a low point of 13 713 km – confusing the Earth sensor used to point its navigation antennas at the ground.

Corrected orbits

A recovery plan was devised between ESA’s Galileo team, flight dynamics specialists at ESA’s ESOC operations centre and France’s CNES space agency, as well as satellite operator SpaceOpal and manufacturer OHB.

This involved gradually raising the lowest point of the satellites’ orbits more than 3500 km while also making them more circular.

The fifth Galileo entered its corrected orbit at the end of November 2014. Both its navigation and search and rescue payloads were switched on the following month to begin testing.

Now the sixth satellite has reached the same orbit, too.

This latest salvage operation began in mid-January and concluded six weeks later, with some 14 manoeuvres performed in total.

Galileo FOC

Its corrected position is effectively a mirror image of the fifth satellite’s, placing the pair on opposite sides of the planet.

The exposure of the two to the harmful Van Allen Belt radiation has been greatly reduced, helping to ensure future reliability.

Significantly, the corrected orbit means they will overfly the same location on the ground every 20 days. This compares with a standard Galileo repeat pattern of every 10 days, helping to synchronise their ground tracks with the rest of the constellation. 

Operations team

The test results from Galileo 5 proved positive, with the same test campaign for the sixth satellite due to begin shortly, overseen by ESA’s Redu centre in Belgium. A 20 m-diameter antenna will study the strength and shape of the navigation signals at high resolution.

“I am very proud of what our teams at ESA and industry have achieved,” says Marco Falcone, head of Galileo system office. “Our intention was to recover this mission from the very early days after the wrong orbit injection. This is what we are made for at ESA.”

The decision whether to use the two satellites for navigation and search-and-rescue purposes will be ultimately taken by the European Commission, as the system owner, based on the in-orbit test results and the system’s ability to provide navigation data from the improved orbits.

The next pair of satellites is due for launch on 27 March.

Related article:

Salvaged Galileo performs its first navigation fix:

Related link:


For more information about Galileo navigation satellites, visit:

Images, Text, Credits: ESA/P. Carril/R. Solaz.

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NASA Spacecraft in Earth’s Orbit, Preparing to Study Magnetic Reconnection

NASA - Magnetospheric Multiscale (MMS) patch.

March 13, 2015

Image above: The United Launch Alliance Atlas V rocket with NASA’s Magnetospheric Multiscale (MMS) spacecraft onboard launches from the Cape Canaveral Air Force Station Space Launch Complex 41, Thursday, March 12, 2015, Florida. Image Credit: NASA.

Following a successful launch at 10:44 p.m. EDT Thursday, NASA’s four Magnetospheric Multiscale (MMS) spacecraft are positioned in Earth’s orbit to begin the first space mission dedicated to the study of a phenomenon called magnetic reconnection. This process is thought to be the catalyst for some of the most powerful explosions in our solar system.

Liftoff of MMS

The spacecraft, positioned one on top of the other on a United Launch Alliance Atlas V 421 rocket, launched from Cape Canaveral Air Force Station, Florida. After reaching orbit, each spacecraft deployed from the rocket’s upper stage sequentially, in five-minute increments, beginning at 12:16 a.m. Friday, with the last separation occurring at 12:31 a.m. NASA scientists and engineers were able to confirm the health of all separated spacecraft at 12:40 a.m.

"I am speaking for the entire MMS team when I say we’re thrilled to see all four of our spacecraft have deployed and data indicates we have a healthy fleet,” said Craig Tooley, project manager at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

Image above: As an Atlas V rocket lifts off from Space Launch Complex 41 at Cape Canaveral Air Force Station in the background, the launch can also be seen on the countdown clock at the Kennedy Space Center's Press Site. The rocket is carrying NASA's Magnetospheric Multiscale, or MMS, spacecraft. Image Credit: NASA/Frankie Martin.

Over the next several weeks, NASA scientists and engineers will deploy booms and antennas on the spacecraft, and test all instruments. The observatories will later be placed into a pyramid formation in preparation for science observations, which are expected to begin in early September.

“After a decade of planning and engineering, the science team is ready to go to work,” said Jim Burch, principal investigator for the MMS instrument suite science team at the Southwest Research Institute in San Antonio (SwRI). “We’ve never had this type of opportunity to study this fundamental process in such detail.”

The mission will provide the first three-dimensional views of reconnection occurring in Earth's protective magnetic space environment, the magnetosphere. Magnetic reconnection occurs when magnetic fields connect, disconnect, and reconfigure explosively, releasing bursts of energy that can reach the order of billions of megatons of trinitrotoluene (commonly known as TNT). These explosions can send particles surging through space near the speed of light.

Scientists expect the mission will not only help them better understand magnetic reconnection, but also will provide insight into these powerful events, which can disrupt modern technological systems such as communications networks, GPS navigation, and electrical power grids.

By studying reconnection in this local, natural laboratory, scientists can understand the process elsewhere, such as in the atmosphere of the sun and other stars, in the vicinity of black holes and neutron stars, and at the boundary between our solar system's heliosphere and interstellar space.

Image above: Artist's concept of the MMS observatory fleet with rainbow magnetic lines. Image Credit: NASA.

The spacecraft will fly in a tight formation through regions of reconnection activity. Using sensors designed to measure the space environment at rates100 times faster than any previous mission.

“MMS is a crucial next step in advancing the science of magnetic reconnection – and no mission has ever observed this fundamental process with such detail,” said Jeff Newmark, interim director for NASA’s Heliophysics Division at the agency’s Headquarters in Washington. “The depth and detail of our knowledge is going to grow by leaps and bounds, in ways that no one can yet predict.”

MMS is the fourth mission in the NASA Solar Terrestrial Probes Program. Goddard built, integrated and tested the four MMS spacecraft and is responsible for overall mission management and operations. The principal investigator for the MMS instrument suite science team is based at the SwRI. Science operations planning and instrument commanding are performed at the MMS Science Operations Center at the University of Colorado Boulder’s Laboratory for Atmospheric and Space Physics. 

More information about the MMS mission is available at:

Images (mentioned), Video, Text, Credits: NASA/Dwayne Brown/Goddard Space Flight Center/Susan Hendrix/NASA TV.


jeudi 12 mars 2015

Rover Arm Delivers Rock Powder Sample

NASA - Mars Science Laboratory (MSL) patch.

March 12, 2015

Mission Status Report

NASA's Curiosity Mars rover used its robotic arm Wednesday, March 11, to sieve and deliver a rock-powder sample to an onboard instrument. The sample was collected last month before the team temporarily suspended rover arm movement pending analysis of a short circuit.

The Chemistry and Mineralogy (CheMin) analytical instrument inside the rover received the sample powder. This sample comes from a rock target called "Telegraph Peak," the third target drilled during about six months of investigating the "Pahrump Hills" outcrop on Mount Sharp. With this delivery completed, the rover team plans to drive Curiosity away from Pahrump Hills in coming days.

Image above: This area at the base of Mount Sharp on Mars includes a pale outcrop, called "Pahrump Hills," that NASA's Curiosity Mars rover investigated from September 2014 to March 2015, and the "Artist's Drive" route toward higher layers of the mountain. Image Credit: NASA/JPL-Caltech/Univ. of Arizona.

"That precious Telegraph Peak sample had been sitting in the arm, so tantalizingly close, for two weeks. We are really excited to get it delivered for analysis," said Curiosity Project Scientist Ashwin Vasavada of NASA's Jet Propulsion Laboratory, Pasadena, California.

The rover experienced a short circuit on Feb. 27 while using percussion action in its drill to shake sample powder from the drill into a sample-processing device on the arm. Subsequent testing at JPL and on Curiosity has identified the likely cause as a transient short in the motor for the drill's percussion action. During several tests on the rover in the past 10 days, the short was reproduced only one time -- on March 5. It lasted less than one one-hundredth of a second and did not stop the motor. Ongoing analysis will help the rover team develop guidelines for best use of the drill at future rock targets.

The rover's path toward higher layers of Mount Sharp will take it first through a valley called "Artist's Drive," heading southwestward from Pahrump Hills. The sample-processing device on the arm is carrying Telegraph Peak sample material at the start of the drive, for later delivery into the Sample Analysis at Mars (SAM) suite of instruments. The delivery will occur after SAM prepares for receiving the sample.

Self-Portrait by Curiosity rover arm camera square. Image Credits: NASA/JPL-Caltech

Curiosity's drill has used a combination of rotary and percussion action to collect samples from six rock targets since the rover landed inside Gale Crater in 2012. The first sampled rock, "John Klein," in the Yellowknife Bay area near the landing site, provided evidence for meeting the mission's primary science goal. Analysis of that sample showed that early Mars offered environmental conditions favorable for microbial life, including the key elemental ingredients for life and a chemical energy source such as used by some microbes on Earth. In the layers of lower Mount Sharp, the mission is pursuing evidence about how early Mars environments evolved from wetter to drier conditions.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Science Laboratory project for NASA's Science Mission Directorate, Washington, and  built the project's Curiosity rover. For more information about Curiosity, visit: and

You can follow the mission on Facebook and Twitter at: and

Images (mentioned), Text, Credits: NASA/JPL/Guy Webster.


Hubble Observations Suggest Underground Ocean on Jupiter's Largest Moon

NASA - Hubble Space Telescope patch.

March 12, 2015

Hubble Space Telescope has the best evidence yet for an underground saltwater ocean on Ganymede, Jupiter’s largest moon. The subterranean ocean is thought to have more water than all the water on Earth's surface.

Identifying liquid water is crucial in the search for habitable worlds beyond Earth and for the search of life as we know it.

Image above: In this artist’s concept, the moon Ganymede orbits the giant planet Jupiter. NASA’s Hubble Space Telescope observed aurorae on the moon generated by Ganymede’s magnetic fields. A saline ocean under the moon’s icy crust best explains shifting in the auroral belts measured by Hubble. Image Credit: NASA/ESA.

“This discovery marks a significant milestone, highlighting what only Hubble can accomplish,” said John Grunsfeld, associate administrator of NASA’s Science Mission Directorate at NASA Headquarters, Washington. “In its 25 years in orbit, Hubble has made many scientific discoveries in our own solar system. A deep ocean under the icy crust of Ganymede opens up further exciting possibilities for life beyond Earth.”

Ganymede is the largest moon in our solar system and the only moon with its own magnetic field. The magnetic field causes aurorae, which are ribbons of glowing, hot electrified gas, in regions circling the north and south poles of the moon. Because Ganymede is close to Jupiter, it is also embedded in Jupiter’s magnetic field. When Jupiter’s magnetic field changes, the aurorae on Ganymede also change, “rocking” back and forth.

By watching the rocking motion of the two aurorae, scientists were able to determine that a large amount of saltwater exists beneath Ganymede’s crust affecting its magnetic field.

A team of scientists led by Joachim Saur of the University of Cologne in Germany came up with the idea of using Hubble to learn more about the inside of the moon.

"I was always brainstorming how we could use a telescope in other ways," said Saur. "Is there a way you could use a telescope to look inside a planetary body? Then I thought, the aurorae! Because aurorae are controlled by the magnetic field, if you observe the aurorae in an appropriate way, you learn something about the magnetic field. If you know the magnetic field, then you know something about the moon’s interior."

Image above: Hubble Space Telescope images of Ganymede's auroral belts (colored blue in this illustration) are overlaid on a Galileo orbiter image of the moon. The amount of rocking of the moon's magnetic field suggests that the moon has a subsurface saltwater ocean. Image Credit: NASA/ESA.

If a saltwater ocean were present, Jupiter’s magnetic field would create a secondary magnetic field in the ocean that would counter Jupiter’s field. This “magnetic friction” would suppress the rocking of the aurorae. This ocean fights Jupiter's magnetic field so strongly that it reduces the rocking of the aurorae to 2 degrees, instead of the 6 degrees, if the ocean was not present.

Scientists estimate the ocean is 60 miles (100 kilometers) thick – 10 times deeper than Earth's oceans – and is buried under a 95-mile (150-kilometer) crust of mostly ice.

Scientists first suspected an ocean in Ganymede in the 1970s, based on models of the large moon. NASA's Galileo mission measured Ganymede's magnetic field in 2002, providing the first evidence supporting those suspicions. The Galileo spacecraft took brief "snapshot" measurements of the magnetic field in 20-minute intervals, but its observations were too brief to distinctly catch the cyclical rocking of the ocean’s secondary magnetic field.

Hubble and the sunrise over Earth

The new observations were done in ultraviolet light and could only be accomplished with a space telescope high above the Earth's atmosphere, which blocks most ultraviolet light.

NASA’s Hubble Space Telescope is celebrating 25 years of groundbreaking science on April 24. It has transformed our understanding of our solar system and beyond, and helped us find our place among the stars. To join the conversation about 25 years of Hubble discoveries, use the hashtag #Hubble25.

Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington.

For images and more information about Hubble, visit: and and

Images (mentioned), Text, Credits: NASA/Felicia Chou/Space Telescope Science Institute/Ann Jenkins/Ray Villard.


Crossing the boundary from high to low on Mars

ESA - Mars Express Mission patch.

12 March 2015

Cydonia Mensae

On the boundary between the heavily cratered southern highlands and the smooth northern lowlands of Mars is an area rich in features sculpted by water and ice.

Cydonia Mensae is a region of mesa-like structures, craters and otherwise smooth terrain. It is home to the so-called ‘Face on Mars’ seen in NASA’s Viking 1 images, but long since known from subsequent higher-resolution imaging to be just an eroded mesa.

Cydonia Mensae in context

The portion of the Cydonia Mensae region shown here lies to the southeast of the Face, and was imaged by ESA’s Mars Express on 19 November 2014.

The region is thought to have hosted ancient seas or lakes that were later covered by hundreds of metres of thick lava and sediment deposits. These deposits were subsequently stripped away by water-driven erosion, leaving the wide debris-filled valleys, scattered mounds and flat-topped mesas of various shapes and sizes.

Some of the remaining mounds have a different surface texture and a higher density of impact craters than their surroundings, suggesting that they were once part of the older southern highlands area.

Cydonia Mensae topography

In the centre of the image there are two large mesas, each roughly 20 km across. Likely once joined together as single block, they are now split by a very broad valley. A much narrower channel cuts through the left-hand (southern) side of the left-hand mesa, with signs of flow all around.

At the lower centre of the image, a 15 km-wide impact crater displays interesting features. Inside its crater walls, material appears to have slumped away from the rim.

Cydonia Mensae – perspective view

Meanwhile, the debris thrown out from the impact forms a double layer – an inner ejecta blanket covering a larger outer one. This can be seen most clearly in the topography image.

Other smaller impact craters across the region also display smooth floors with raised rims and rounded rings of ejecta around them. This characteristic form suggests that the impacts were into an ice- or water-saturated terrain, which became fluidised and mixed with the rock as the craters formed.

Cydonia Mensae in 3D

The dichotomy between the rugged southern highlands and smoother northern lowlands is crucial to understanding the overall geological history of the Red Planet, and regions like this transition zone in Cydonia provide a particularly rich set of important clues.

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Editor note: Free scenery add-on for Orbiter Space Flight Simulator 2010 of the "Mars Face" made by Aerospace are available for free download on my website:

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Images, Text, Credits: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO/NASA MGS MOLA Science Team.

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mercredi 11 mars 2015

Space Station Crew Returns to Earth, Lands Safely in Kazakhstan

ROSCOSMOS - Soyuz TMA-14M Mission patch.

March 11, 2015

 Expedition 42 Returns to Earth. Image Credits: NASA/Bill Ingalls

Three crew members returned to Earth Wednesday after a 167-day mission on the International Space Station (ISS) that included hundreds of scientific experiments and several spacewalks to prepare the orbiting laboratory for future arrivals by U.S. commercial crew spacecraft.

Image above: ЕСТЬ ПОСАДКА! They have landed! This message was posted to the center screen of the Russian Federal Space Agency's Mission Control Center in Korolev, Russia, the moment confirmation was received that the Soyuz carrying three crew members of the International Space Station's Expedition 42 had landed on time and target in Kazakhstan. Image Credit: NASA.

Expedition 42 commander Barry Wilmore of NASA and flight engineers Alexander Samokutyaev and Elena Serova of the Russian Federal Space Agency (Roscosmos) touched down at approximately 10:07 p.m. EDT (8:07 a.m. March 12, Kazakh time) southeast of the remote town of Dzhezkazgan in Kazakhstan.

During their time on station, the crew members participated in a variety of research focusing on the effects of microgravity on cells, Earth observation, physical science and biological and molecular science. One of several key research focus areas during Expedition 42 was human health management for long-duration space travel, as NASA and Roscosmos prepare for two crew members to spend one year aboard the space station.

Image above: Expedition 42 commander Barry Wilmore of NASA makes his way out of the Soyuz spacecraft following the crew's 167-day mission aboard the space station. Image Credit: NASA.

The space station also serves as a test bed to demonstrate new technology. The Cloud-Aerosol Transport System (CATS) arrived and was installed during Expedition 42, and already is providing data to improve scientists’ understanding of the structure and evolution of Earth's atmosphere. This may lead to enhancements to spacecraft launches, landings and communications systems; help guide future atmospheric investigations of Mars, Jupiter or other worlds; and help researchers model and predict climate changes on Earth.

The newly installed Electromagnetic Levitator will allow scientists to observe fundamental physical processes as liquid metals cool, potentially leading to lighter, higher-performing alloy, mixtures of two or more metals or a metal and another material, for use on Earth and in space.

Image above: Her first mission to the space station, Expedition 42 flight engineer Elena Serova of the Russian Federal Space Agency is assisted in her exit from the Soyuz that returned her and her team members from the ISS. Image Credit: NASA.

The station crew also welcomed three cargo spacecraft with several tons of scientific investigations, food, fuel and other supplies. In January, the trio helped grapple and connect a SpaceX Dragon spacecraft on the company's fifth contracted commercial resupply mission to the station. The Dragon returned to Earth in February with critical science samples. Two Russian ISS Progress cargo craft docked to the station in October and February. The fifth and final European Automated Transfer Vehicle, bearing the name of Belgian physicist Georges Lemaître, considered the father of the big-bang theory, departed the station in February.

During his time on the orbital complex, Wilmore ventured outside the space station with NASA astronaut Terry Virts on three spacewalks to prepare for new international docking adapters and future U.S. commercial crew spacecraft. Wilmore also completed a spacewalk in October with fellow NASA astronaut Reid Wiseman to replace a failed voltage regulator. Samokutyaev conducted one spacewalk during his time in space.

Image above: With the end of this mission, flight engineer Alexander Samokutyaev of the Russian Federal Space Agency now has accrued 331 days in space. Image Credit: NASA.

Having completed his second space station mission, Samokutyaev now has spent 331 days in space. Wilmore, having previously flown as a shuttle pilot on STS-129, has spent 178 days in space. Serova spent 167 days in space on her first flight.

Expedition 43 currently is operating the station, with Virts in command. Flight engineers Anton Shkaplerov of Roscosmos and Samantha Cristoforetti of ESA (European Space Agency), are continuing station research and operations until three new crewmates arrive in two weeks. NASA’s Scott Kelly and Roscosmos’ Mikhail Kornienko and Gennady Padalka are scheduled to launch from Kazakhstan March 27, Eastern time. Kelly and Kornienko will embark on the first joint U.S.-Russian one-year mission, an important stepping stone on NASA’s journey to Mars.

For more information about the International Space Station and its crews, visit:

For b-roll and other media resources, visit:

Follow the station on Twitter at @Space_Station

Images (mentioned), Text, Credits: ROSCOSMOS/NASA/Stephanie Schierholz/Johnson Space Center/Dan Huot.


Waiting for a signal from Philae

ESA - Rosetta Mission patch.

March 11, 2015

Image above: Comet on 6 March 2015 (b) – NavCam. Image Credits: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0.

This week, Rosetta will begin listening for signs that Philae is still “alive”. This report is provided by the German Aerospace Center, DLR.

It would be very lucky if a signal were to be received from Philae at 05:00 CET on 12 March 2015. The lander finally came to rest on 12 November 2014 in a rather shaded location on Comet 67P/Churyumov-Gerasimenko and it needs to receive sufficient energy before it can wake up and begin communicating. This is, however, the first possibility to receive a signal from Philae; therefore, the communication unit on the Rosetta orbiter will be switched on to call the lander.

“Philae currently receives about twice as much solar energy as it did in November last year,” says Lander Project Manager Stephan Ulamec from the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR).

Today, Comet 67P/Churyumov-Gerasimenko, Rosetta and Philae are 320 million kilometres from the Sun.

“It will probably still be too cold for the lander to wake up, but it is worth trying. The prospects will improve with each passing day,” says Ulamec.

Waking up at the right temperature and energy

Several conditions must be met for Philae to start operating again and allow the DLR Lander Control Center to put it to work. First, the interior of the lander must be at least at –45ºC before Philae can wake up from its winter sleep. At its new landing site – Abydos – only a little sunlight reaches Philae, and the temperatures are significantly lower than at the originally planned landing location. In addition, the lander must be able to generate at least 5.5 watts using its solar panels to wake up. It has not remained idle during hibernation.

Image above: Philae's view of the cliffs at Abydos. One of the lander's three feet can be seen in the foreground. Image Credits: ESA/Rosetta/Philae/CIVA.

“Philae is designed so that, since November 2014, it has been using all the available solar energy to heat up,” says Koen Geurts from the DLR Control Center.

As soon as Philae ‘realises’ that it is receiving more than 5.5 watts of power and its internal temperature is above –45ºC, it will turn on, heat up further and attempt to charge its battery.

Contact during comet daytime

Once awakened, Philae switches on its receiver every 30 minutes and listens for a signal from the Rosetta orbiter. This, too, can be performed in a very low power state.

“At this time, we do not yet know that the lander is awake,” says Geurts. “To send us an answer, Philae must also turn its transmitter – and that requires additional power.”

Image above: Comet on 6 March 2015 – NavCam. Image Credits:  ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0.

It could be that the lander has already woken up from its winter sleep some 500 million kilometres away from Earth, but does not yet have sufficient power to communicate with Rosetta, which relays Philae’s signal back to Earth. Philae needs a total of 19 watts to begin operating and allow two-way communication.

Between 12 and 20 March, the Rosetta orbiter is transmitting to the lander and listening for a response. The most likely time for contact is during the 11 flybys where the orbiter’s path puts it in a particularly favourable position with respect to the lander during comet ‘daytime’ – when Philae is in sunlight and being supplied with power by its solar panels. Communication will be attempted continuously because Philae’s environment could have changed since landing in November 2014.

Preparation for all eventualities

So far, Philae’s exact location has not been identified on images acquired by the Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) on board the Rosetta orbiter, so the operations team at DLR is currently working with the information they have from the lander’s cameras: the Comet nucleus Infrared and Visible Analyser (CIVA) and the ROsetta Lander Imaging System (ROLIS), along with the knowledge gained from the solar energy conditions experienced in November.

Image above: Lander search area. The image is a 2 x 2 mosaic comprising OSIRIS narrow-angle camera images taken on 13 December 2014 from a distance of about 20 km to the centre of the comet.Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA.

“However, we assume that the solar panels of Philae are shadowed but, by what, we cannot see in the previous images,” says Geurts.

The DLR engineers have therefore sent new commands to the lander that optimise the heating and provide energy savings to improve its chances of communication with Earth. Even if Philae does not have enough energy yet to answer, it could receive and execute these commands. This is referred to as ‘blind commanding’ by the engineers, because the lander is initially very unlikely give them feedback. These procedures were tested on the ground model at the DLR Microgravity User Support Center (MUSC). Even in the event that the rechargeable battery on board Philae did not survive the cold phase, the engineers are prepared.

“We are working to ensure that we can operate the lander and its instruments at least during the comet’s daytime, when it is in direct sunlight,” says Geurts.

Waiting for the health check

Once Philae wakes up and can also transmit, it will first send data about its ‘health’ to Earth.

“We will then evaluate the data. What is the state of the rechargeable battery? Is everything on the lander still functioning? What is the temperature? How much energy is it receiving?” says Geurts.

Philae's instruments. Credits: ESA/ATG medialab

The scientific work with the 10 instruments on board Philae also depends on these results. If sufficient energy cannot be stored in the battery, the solar energy available during the comet daytime will determine whether a reduced version of the measurements can be performed. Currently, scientists believe that Philae is in sunlight for 1.3 hours. A day on 67P/Churyumov-Gerasimenko lasts 12.4 hours. If the battery can be charged as planned, measurements can be carried out during the comet night, enabling, for example, long-term measurements. What instrument is used and when will be determined by the team of scientists.

“If we cannot establish contact with Philae before 20 March, we will make another attempt at the next opportunity,” says Ulamec. “Once we can communicate with Philae again, the scientific work can begin.”

As the distance to the Sun decreases, the energy that the lander collects with its solar panels is becoming greater.

For more information about Rosetta mission, visit:

Images (mentioned), Text, Credit: ESA.

Best regards,

Homecoming Day for Expedition 42 Trio

ROSCOSMOS - Soyuz TMA-14M Mission patch.

March 11, 2015

Today is homecoming day for International Space Station Commander Barry “Butch” Wilmore of NASA and Flight Engineers Alexander Samokutyaev and Elena Serova of the Russian Federal Space Agency (Roscosmos) as they prepare for landing in their Soyuz TMA-14M spacecraft at 10:07 p.m. EDT this evening, southeast of Dzhezkazgan, Kazakhstan.

Image above: NASA astronaut Barry Wilmore (left), Expedition 41 flight engineer and Expedition 42 commander; Russian cosmonauts Alexander Samokutyaev and Elena Serova, both Expedition 41/42 flight engineers, attired in Russian Sokol launch and entry suits, take a break from training in Star City, Russia to pose for a portrait. Photo credit: Gagarin Cosmonaut Training Center.

At this time, there are no concerns or issues being worked.

Wilmore handed over command of the orbiting complex to fellow NASA astronaut Terry Virts in a ceremony on Tuesday, March 10. When the Soyuz undocks, Expedition 43 formally will begin.

Expedition 42 crew members Barry Wilmore of NASA and Alexander Samokutyaev and Elena Serova of Roscosmos are set to land in Kazakhstan at  10:07 p.m. EDT. The trio left the International Space Station earlier tonight after spending 167 days on the orbital outpost.

Expedition 42 Trio Enters Soyuz and Closes Hatches

Image above: The Expedition 42 trio of station Commander Barry Wilmore, Soyuz Commander Alexander Samokutyaev and Flight Engineer Elena Serova says goodbye to their station crewmates before entering their Soyuz TMA-14M spacecraft. Image Credit: NASA TV.

At 3:34 p.m. EDT, the Soyuz hatch closed between the International Space Station and the TMA-14M spacecraft. Expedition 42 crew members Barry Wilmore of NASA and Alexander Samokutyaev and Elena Serova of Roscosmos are preparing to undock at 6:44 p.m. NASA Television will air live coverage of undocking beginning at 6:15 p.m.

 ISS Exp 42 Farewells and Hatch Closure

The deorbit burn is targeted for 9:16 p.m. and will lead to a landing at 10:07 p.m. southeast of Dzhezkazgan in Kazakhstan. NASA TV coverage of deorbit and landing begins at 9 p.m. Watch live at

Expedition 42 Trio Undocks for Voyage Home

After spending 167 days aboard the International Space Station, Barry Wilmore, Alexander Samokutyaev and Elena Serova undocked from the station at 6:44 p.m. EDT to begin their voyage home. Samokutyaev, the Soyuz commander, is at the controls of the Soyuz TMA-14M spacecraft.

Image above: The Soyuz TMA-14M spacecraft undocks with the Expedition 42 trio and backs away from the Poisk module of the International Space Station. Image Credit: NASA TV.

They will perform a separation burn to increase the distance from the station before executing a 4-minute, 41-second deorbit burn at 9:16 p.m. The crew is scheduled to land at 10:07 p.m. southeast of Dzhezkazgan, Kazakhstan.

The departure of Wilmore, Samokutyaev and Serova marks the end of Expedition 42. The Expedition 43 crew members, Commander Terry Virts of NASA, Samantha Cristoforetti of ESA and Anton Shkaplerov of Roscosmos will continue research and maintenance aboard the station and will be joined on March 27 by three additional crew members, NASA’s Scott Kelly and Roscosmos’ Mikhail Kornienko and Gennady Padalka.

For more information about the International Space Station (ISS), visit:

Images (mentioned), Video, Text, Credit: NASA / NASA TV.


Sun Emits Significant Solar Flare

NASA - Solar Dynamics Observatory (SDO) patch.

March 11, 2015

Image above: NASA's Solar Dynamics Observatory captured an image of a mid-level solar flare on March 11, 2015, seen as a bright flash of light on the left side of the sun. Earth is shown for scale. Image Credit: NASA/SDO.

The sun emitted a significant solar flare, peaking at 12:22 p.m. EDT on March 11, 2015. NASA’s Solar Dynamics Observatory, which watches the sun constantly, captured an image of the event. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel.

Sun Unleashes an X-Class Flare on March 11, 2015

Video above: This movie shows an X2.2-class solar flare on March 11, 2015. The imagery was captured by NASA’s Solar Dynamics Observatory in extreme ultraviolet light. Image Credit: NASA/SDO.

To see how this event may affect Earth, please visit NOAA's Space Weather Prediction Center at, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.

This flare is classified as an X2.2-class flare. X-class denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc. 

Updates will be provided as needed.

What is a solar flare?

For answers to this and other space weather questions, please visit the Spaceweather Frequently Asked Questions page:

Related Links:

Download high resolution media of this event:

View Past Solar Activity:

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


Hot water activity on icy moon’s seafloor

ESA - Cassini Insider's logo.

11 March 2015

Tiny grains of rock detected by the international Cassini spacecraft orbiting Saturn point to hydrothermal activity on the seafloor of its icy moon Enceladus.

The finding adds to the tantalising possibility that the moon could contain environments suitable for living organisms.

Hydrothermal activity on Enceladus

Understanding the interior structure of 500 km-diameter Enceladus has been a top priority of the Cassini mission since plumes of ice and water vapour were discovered jetting from fractures at the moon’s south pole in 2005.

Ice particles in the plumes were found to be rich in sodium salt, implying that the water has been in contact with rock, and subsequent measurements of the moon’s gravitational field revealed a 10 km deep subsurface ocean at the south pole, below a 30–40 km thick ice crust.

Now, following an extensive, four-year study of data from the spacecraft, combined with computer simulations and laboratory experiments, scientists have been able to gain deeper insights into the chemical reactions taking place on the floor at the base of Enceladus’s ocean.

Using Cassini’s Cosmic Dust Analyser, scientists have discovered a population of tiny dust grains, just 2–8 nm in radius, in orbit around Saturn. They are rich in silicon, marking them out from the water-ice particles that dominate in the planet’s environment, including in its famous ring system.

Enceladus plumes

They believe that these silicon-rich grains originate on the seafloor of Enceladus, where hydrothermal processes are at work. On the seafloor, hot water at a temperature of at least 90 degrees Celsius dissolves minerals from the moon’s rocky interior. The origin of this energy is not well understood, but likely includes a combination of tidal heating as Enceladus orbits Saturn, radioactive decay in the core and chemical reactions.

As the hot water travels upward, it comes into contact with cooler water, causing the minerals to condense out and form nano-grains of ‘silica’ floating in the water.

To avoid growing too large, these silica grains must spend a few months to several years at most rising from the seafloor to the surface of the ocean, before being incorporated into larger ice grains in the vents that connect the ocean to the surface of Enceladus. After being ejected into space via the moon’s geysers, the ice grains erode, liberating the tiny rocky inclusions subsequently detected by Cassini.

“It’s very exciting that we can use these tiny grains of rock, spewed into space by geysers, to tell us about conditions on – and beneath – the ocean floor of an icy moon,” says Sean Hsu, a postdoctoral researcher at the University of Colorado at Boulder and lead author on the paper published today in the journal Nature.

On Earth, grains of silica are found in sand and the mineral quartz. The most common way to form small silica grains is through hydrothermal activity involving a specific range of conditions. In particular, such grains form when slightly alkaline water with modest salt content and super-saturated with silica undergoes a big drop in temperature.

Image above: This illustration depicts potential origins of methane found in the plume of gas and ice particles that sprays from Enceladus, based on research by scientists working with the Cassini Ion and Neutral Mass Spectrometer. Image Credit: NASA/JPL.

“We methodically searched for alternative explanations for the nanosilica grains, but every new result pointed to a single, most likely origin,” says Frank Postberg, a Cassini Cosmic Dust Analyser scientist at the University of Heidelberg in Germany, and a co-author on the paper.

Hsu and Postberg worked closely with colleagues at the University of Tokyo who performed the detailed laboratory experiments that validated the hydrothermal activity hypothesis.

Furthermore, Cassini’s gravity measurements suggest that the rocky core of Enceladus is quite porous, which would allow water from the ocean to percolate into the interior. This would provide a huge surface area where rock and water could interact.

“In fact, it’s possible much of this interesting hot-water chemistry occurs deep inside the moon’s core, not just at the seafloor,” says Hsu.

In another paper, published in Geophysical Research Letters last month, Cassini scientists also reported on the abundance of methane spewing into the atmosphere of Enceladus. The methane could also be produced by hydrothermal processes at the rock-water boundary at the bottom of Enceladus’s ocean, and/or by the melting of a type of methane-rich ice, before subsequently percolating to the surface.


“This moon has all the ingredients – water, heat, and minerals – to support habitability in the outer Solar System, confirming the astrobiological potential of Enceladus,” adds Nicolas Altobelli, ESA’s Cassini project scientist.

“Enceladus may even represent a very common habitat in the Galaxy: icy moons around giant gas planets, located well beyond the ‘habitable zone’ of a star, but still able to maintain liquid water below their icy surface.”

Notes for Editors:

“Ongoing hydrothermal activities within Enceladus,” by H-W. Hsu et al., is published in the 12 March issue of Nature.

“Possible evidence for a methane source in Enceladus’ ocean,” by A. Bouquet et al., is published in the 26 February 2015 issue of the Geophysical Research Letters.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency, and ASI, the Italian space agency. NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate in Washington DC.

The Cassini Cosmic Dust Analyser was provided by the German Aerospace Center; the instrument team is lead by Ralf Srama and is based at the University of Stuttgart in Germany.

Related links:

At Saturn and Titan:

Cassini-Huygens in depth:

NASA JPL Cassini site:

Italian Space Agency:

Images, Text, Credits: ESA/NASA/JPL-Caltech/Space Science Institute.

Best regards,

A Grand Extravaganza of New Stars

ESO - European Southern Observatory logo.

11 March 2015

Star cluster NGC 6193 and nebula NGC 6188

This dramatic landscape in the southern constellation of Ara (The Altar) is a treasure trove of celestial objects. Star clusters, emission nebulae and active star-forming regions are just some of the riches observed in this region lying some 4000 light-years from Earth. This beautiful new image is the most detailed view of this part of the sky so far, and was taken using the VLT Survey Telescope at ESO’s Paranal Observatory in Chile.

At the centre of the image is the open star cluster NGC 6193, containing around thirty bright stars and forming the heart of the Ara OB1 association. The two brightest stars are very hot giant stars. Together, they provide the main source of illumination for the nearby emission nebula, the Rim Nebula, or NGC 6188, which is visible to the right of the cluster.

The open star cluster NGC 6193 in the constellation of Ara

A stellar association is a large grouping of loosely bound stars that have not yet completely drifted away from their initial formation site. OB associations consist largely of very young blue–white stars, which are about 100 000 times brighter than the Sun and between 10 and 50 times more massive.

The Rim Nebula is the prominent wall of dark and bright clouds marking the boundary between an active star-forming region within the molecular cloud, known as RCW 108, and the rest of the association [1]. The area around RCW 108 is made up of mostly hydrogen — the primary ingredient in star formation. Such areas are also known as H II regions.

Zooming in on the star cluster NGC 6193 and nebula NGC 6188

The ultraviolet radiation and intense stellar wind from the stars of NGC 6193 seem to be driving the next generation of star formation in the surrounding clouds of gas and dust. As cloud fragments collapse they heat up and eventually form new stars.

As the cloud creates new stars, it is simultaneously being eroded by the winds and radiation emitted by previous stars, and by violent supernova explosions. In this way, such star-forming H II regions tend to have a lifespan of just a few million years. Star formation is a very inefficient process, with only around 10% of the available material contributing to the process — the rest is blown off into space.

Close-up view of the star cluster NGC 6193 and nebula NGC 6188

The Rim Nebula also shows signs of being in the early phase of “pillar formation”, meaning that in the future it could end up looking similar to other well-known star-forming regions, such as the Eagle Nebula (Messier 16, containing the famous Pillars of Creation) and the Cone Nebula (part of NGC 2264).

This single spectacular image was actually created from more than 500 individual pictures taken through four different colour filters with the VLT Survey Telescope. The total exposure time was more than 56 hours. It is the most detailed view of this region yet achieved.


[1] Furthermore, this nebula has additional modest fame among astronomers, as a previous image was used as the cover of the DVD distribution of the collection of software for astronomers assembled by ESO: Scisoft, whose newest version was released a few weeks ago. It is therefore also known as the Scisoft Nebula.
More information

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.


Research papers on Ara OB1:

Previous images of NGC 6193:

Photos of ESO’s survey telescopes:

Images, Text, Credits: ESO/IAU, and Sky & Telescope/Videos: ESO/Digitized Sky Survey 2/N. Risinger ( Music: movetwo.

Best regards,