samedi 17 février 2018

Space Station Science Highlights: Week of Feb 12, 2018

ISS - Expedition 54 Mission patch.

Feb. 17, 2018

The crew members aboard the International Space Station spent the week conducting science, unloading a newly-arrived cargo delivery and preparing for a Friday morning spacewalk with NASA astronaut Mark Vande Hei and JAXA astronaut Norishige Kanai.

Animation above: The Transparent Alloys was reinstalled within the Microgravity Science Glovebox this week, as seen above. Animation Credit: NASA.

Take a more detailed look at some of the science that happened last week aboard your orbiting laboratory:

Double grow-out continues within Veg-03 investigation

The Veg-03 investigation within the Vegetable Production Facility (Veggie) expands on previous validation tests of the Veggie hardware, which crew members use to grow cabbage, lettuce and other fresh vegetables in space. This marks the first time that two grow-outs have been initiated using two Veggie facilities in parallel aboard the space station. These plants will provide the crew the opportunity to consume fresh vegetables every few days, while some of the products from this run will be returned to Earth for testing. This week, the crew members, or space gardeners, worked to maintain the plants growing within the plant pillows by thinning the plants and priming the pillows.

International Space Station (ISS). Image Credit: NASA

JAXA astronaut demonstrates microgravity’s impact on everyday tasks

In addition to spacewalk preparations, Kanai also spent time teaching children and adults how microgravity impacts everyday tasks. Try Zero-G for Asia gives the public, including children and adults, the opportunity to vote for and suggest tasks for JAXA crew members, demonstrating the difference between Earth’s gravity and the microgravity environment of the space station. This week, Kanai demonstrated the use of a variety of objects including a paper boomerang, a paper airplane, a gyroscope, a slinky and liquids.

Investigation tests new method of storm intensity measurement

Image above: A view of Typhoon Gita, near the South Pacific island nation of tonga, taken as a part of the Tropical Cyclone investigation. Image Credit: NASA.

The Cyclone Intensity Measurements from the ISS (Tropical Cyclone) investigation captures images of tropical cyclones and hurricanes that are rated at Category 3 or greater on the Saffir-Simpson scale. A pseudo-stereoscopic method is used to determine the altitudes of the cloud tops near the eye of a cyclone by precisely tracking the positions of cloud features with respect to the Earth and how those positions change over time as an observer, the space station in this case, passes over the storm. The images demonstrate that pseudo-spectroscopy can be used to measure the cloud altitudes to sufficient precision so that, when combined with other remote-sensing data, an accurate determination of the intensity of hurricane or cyclone can be made. This week, the crew configured the camera settings in the Cupola to take untended images of the Category 3 Typhoon Gita, near the South Pacific island nation of Tonga.

Other work was done on these investigations: Personal CO2 Monitor, Crew Earth Observations, CLD FLAME, Microbial Tracking-2, Neuromapping, Space Headaches, Lighting Effects, Transparent Alloys, DOSIS-3D, AstroPi, EIISS, Manufacturing Device, VESSEL ID, Plant Gravity Perception, CBEF, Rodent Research-6, BioLab, and DreamXCG.

Space to Ground: Light Storm: 02/16/2018

Related links:

Vegetable Production Facility (Veggie):


Try Zero-G for Asia:

Personal CO2 Monitor:

Crew Earth Observations:


Microbial Tracking-2:


Space Headaches:

Lighting Effects:

Transparent Alloys:



Manufacturing Device:


Plant Gravity Perception:


Rodent Research-6:



Space Station Research and Technology:

International Space Station (ISS):

Images (mentioned), Animation (mentioned), Video, Text, Credits: NASA/Michael Johnson/John Love, Lead Increment Scientist Expeditions 53 & 54.

Best regards,

vendredi 16 février 2018

Hubble's Window into the Cosmic Past

NASA - Hubble Space Telescope patch.

Feb. 16, 2018

This image from the NASA/ESA Hubble Space Telescope shows the galaxy cluster PLCK G004.5-19.5. It was discovered by the ESA Planck satellite through the Sunyaev-Zel’dovich effect — the distortion of the cosmic microwave background radiation in the direction of the galaxy cluster by high-energy electrons in the intracluster gas. The large galaxy at the center is the brightest galaxy in the cluster, and above it a thin, curved gravitational lens arc is visible. This arc is caused by the gravitational forces of the cluster bending the path of light from stars and galaxies behind it, in a similar way to how a glass lens bends light.

Several stars are visible in front of the cluster — recognizable by their diffraction spikes — but aside from these, all other visible objects are distant galaxies. Their light has become redshifted by the expansion of space, making them appear redder than they actually are. By measuring the amount of redshift, we know that it took more than 5 billion years for the light from this galaxy cluster to reach us. The light of the galaxies in the background had to travel even longer than that, making this image an extremely old window into the far reaches of the universe.

This image was taken by Hubble’s Advanced Camera for Surveys (ACS) and Wide Field Camera 3 (WFC3) as part of an observing program called RELICS (Reionization Lensing Cluster Survey). RELICS imaged 41 massive galaxy clusters with the aim of finding the brightest distant galaxies for the forthcoming NASA James Webb Space Telescope to study.

Hubble Space Telescope (HST)

For more information about Hubble, visit:

Image, Animation, Credits: ESA/Hubble & NASA, RELICS; Acknowledgement: D. Coe et al./Text: European Space Agency/NASA/Karl Hille.

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Jupiter’s Swirling Cloud Formations

NASA - JUNO Mission logo.

Feb. 16, 2018

See swirling cloud formations in the northern area of Jupiter's north temperate belt in this new view taken by NASA’s Juno spacecraft.

The color-enhanced image was taken on Feb. 7 at 5:42 a.m. PST (8:42 a.m. EST), as Juno performed its eleventh close flyby of Jupiter. At the time the image was taken, the spacecraft was about 5,086 miles (8,186 kilometers) from the tops of the clouds of the planet at a latitude of 39.9 degrees.

Citizen scientist Kevin M. Gill processed this image using data from the JunoCam imager.

Juno spacecraft orbiting Jupiter

JunoCam's raw images are available for the public to peruse and process into image products at:

More information about Juno is at: and

Image, Animation, Text, Credits: NASA/Tony Greicius/JPL-Caltech/SwRI/MSSS/Kevin M. Gill.


Spacewalkers Wrap Up Robotic Hand Transfers

ISS - Expedition 54 Mission patch / EVA - Extra Vehicular Activities patch.

February 16, 2018

Expedition 54 Flight Engineers Mark Vande Hei of NASA and Norishige Kanai of the Japan Aerospace Exploration Agency have completed a spacewalk lasting 5 hours and 57 minutes.

Image above: Spacewalkers Mark Vande Hei (foreground) and Norishige Kanai transfer a spare robotic hand to a long-term stowage area on the International Space Station. Image Credit: NASA TV.

The two astronauts concluded their spacewalk at 12:57 p.m. EST with the repressurization of the Quest airlock.

The spacewalkers moved two Latching End Effector (LEE), or hands, for the Canadian-built robotic arm, Canadarm2. They moved one to a long-term storage location for future use as a spare part and brought the other inside the space station to be returned to Earth. It will be refurbished and later relaunched to the orbiting laboratory as a spare.

Image above: Spacewalkers Mark Vande Hei (attached to the Canadarm2 robotic arm) and Norishige Kanai are working ahead of today’s spacewalk timeline. Image Credit: NASA TV.

Running well ahead of the timeline, the two spacewalkers also conducted a number of get ahead tasks, including the lubrication of the inside of the LEE installed on the International Space Station’s robotic arm during the Jan. 23 spacewalk. They also positioned an interface tool for the Canadian Space Agency’s robotic handyman Dextre, installed a grounding strap on a component of the LEE positioned on one end of the robotic arm, and adjusted a strut on a component on one of the station’s spare parts platforms. That component is a flex hose rotary coupler that transfers liquid ammonia across a connecting point on the station’s backbone to provide cooling for its systems.

It was the 208th spacewalk in support of International Space Station assembly and maintenance, the fourth in Vande Hei’s career, and the first for Kanai, who became the fourth Japanese astronaut to walk in space.

Related links:



Expedition 54:

Space Station Research and Technology:

International Space Station (ISS):

Images (mentioned), Text, Credits: NASA/Mark Garcia.

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Long-Lived Mars Rover Opportunity Keeps Finding Surprises

NASA - Mars Exploration Rover B (MER-B) patch.

February 16, 2018

NASA's Mars Exploration Rover Opportunity keeps providing surprises about the Red Planet, most recently with observations of possible "rock stripes."

Rock Stripes Pattern in Mars' 'Perseverance Valley'

Image above: Textured rows on the ground in this portion of "Perseverance Valley" are under investigation by NASA's Mars Exploration Rover Opportunity, which used its Navigation Camera to take the component images of this downhill-looking scene. The rover reaches its 5,000th Martian day, or sol, on Feb. 16, 2018. Image Credits: NASA/JPL-Caltech.

The ground texture seen in recent images from the rover resembles a smudged version of very distinctive stone stripes on some mountain slopes on Earth that result from repeated cycles of freezing and thawing of wet soil. But it might also be due to wind, downhill transport, other processes or a combination.

Opportunity landed on Mars in January 2004. As it reaches the 5,000th Martian day, or sol, of what was planned as a 90-sol mission, it is investigating a channel called "Perseverance Valley," which descends the inboard slope of the western rim of Endeavour Crater.

"... we're seeing surfaces that look like stone stripes. It's mysterious. It's exciting." - Opportunity Deputy Principal Investigator Ray Arvidson, Washington University in St. Louis.

"Perseverance Valley is a special place, like having a new mission again after all these years," said Opportunity Deputy Principal Investigator Ray Arvidson of Washington University in St. Louis. "We already knew it was unlike any place any Mars rover has seen before, even if we don't yet know how it formed, and now we're seeing surfaces that look like stone stripes. It's mysterious. It's exciting. I think the set of observations we'll get will enable us to understand it."

Opportunity Rover Views Ground Texture 'Perseverance Valley'

Image above: This late-afternoon view from the front Hazard Avoidance Camera on NASA's Mars Exploration Rover Opportunity shows a pattern of rock stripes on the ground, a surprise to scientists on the rover team. It was taken in January 2018, as the rover neared Sol 5000 of what was planned as a 90-sol mission. Image Credits: NASA/JPL-Caltech.

On some slopes within the valley, the soil and gravel particles appear to have become organized into narrow rows or corrugations, parallel to the slope, alternating between rows with more gravel and rows with less.

The origin of the whole valley is uncertain. Rover-team scientists are analyzing various clues that suggest actions of water, wind or ice. They are also considering a range of possible explanations for the stripes, and remain uncertain about whether this texture results from processes of relatively modern Mars or a much older Mars.

Other lines of evidence have convinced Mars experts that, on a scale of hundreds of thousands of years, Mars goes through cycles when the tilt or obliquity of its axis increases so much that some of the water now frozen at the poles vaporizes into the atmosphere and then becomes snow or frost accumulating nearer the equator.

"One possible explanation of these stripes is that they are relics from a time of greater obliquity when snow packs on the rim seasonally melted enough to moisten the soil, and then freeze-thaw cycles organized the small rocks into stripes," Arvidson said. "Gravitational downhill movement may be diffusing them so they don't look as crisp as when they were fresh."

Rock Stripe Pattern on Hawaii's Mauna Kea

Image above: This image shows stone stripes on the side of a volcanic cone on Mauna Kea, Hawaii. The stripes are made of small rock fragments and they are aligned downhill as freeze-thaw cycles have lifted them up and out of the finer-grained regolith, and moved them to the sides, forming stone stripes. Image Credits: Washington University in St. Louis/NASA.

Bernard Hallet of the University of Washington, Seattle, agrees the alignments seen in images of Perseverance Valley are not as distinctive as the stone stripes he has studied on Earth. Field measurements on Earth, near the summit of Hawaii's Mauna Kea where the soil freezes every night but is often dry, have documented how those form when temperature and ground conditions are right: Soils with a mix of silt, sand and gravel expand more where the finer-grain material is most prevalent and retains more water. Freezing expands the soil, pushing larger particles up. If they move to the side, as well as down the general slope, due to gravity or wind, they tend to move away from the finer-grain concentrations and stretch out downslope. Where larger particles become more concentrated, the ground expands less. The process repeats hundreds or thousands of times, and the pattern self-organizes into alternating stripes.

Perseverance Valley holds rocks carved by sand blowing uphill from the crater floor, and wind might also be the key in sorting larger particles into rows parallel to the slope.

Mars Exploration Rover. Image Credits: NASA/JPL-Caltech

"Debris from relatively fresh impact craters is scattered over the surface of the area, complicating assessment of effects of wind," said Opportunity science-team member Robert Sullivan of Cornell University, Ithaca, New York. "I don't know what these stripes are, and I don't think anyone else knows for sure what they are, so we're entertaining multiple hypotheses and gathering more data to figure it out."

Related article:

5,000 Days on Mars; Solar-Powered Rover Approaching 5,000th Martian Dawn

Every sol Opportunity keeps working may add information to help solve some puzzles and find new ones. For more information about Opportunity, visit:

Images (mentioned), Text, Credits: NASA/Laurie Cantillo/Dwayne Brown/JPL/Guy Webster/Andrew Good.

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5,000 Days on Mars; Solar-Powered Rover Approaching 5,000th Martian Dawn

NASA / JPL - Mars Exploration Rover (MER) patch.

February 16, 2018

Martian 'Perseverance Valley' in Perspective (Vertical Exaggeration)

Image above: The channel descending a Martian slope in this perspective view is "Perseverance Valley," the study area of NASA's Mars rover Opportunity as the rover passes its 5,000th Martian day. The view overlays a HiRISE image onto a topographic model with five-fold vertical exaggeration, to show shapes. Image Credits: NASA/JPL-Caltech/Univ. of Arizona/WUSTL.

The Sun will rise on NASA's solar-powered Mars rover Opportunity for the 5,000th time on Saturday, sending rays of energy to a golf-cart-size robotic field geologist that continues to provide revelations about the Red Planet.

"Five thousand sols after the start of our 90-sol mission, this amazing rover is still showing us surprises on Mars," said Opportunity Project Manager John Callas, of NASA's Jet Propulsion Laboratory, Pasadena, California.

A Martian "sol" lasts about 40 minutes longer than an Earth day, and a Martian year lasts nearly two Earth years. Opportunity's Sol 1 was landing day, Jan. 25, 2004 (that's in Universal Time; it was Jan. 24 in California). The prime mission was planned to last 90 sols. NASA did not expect the rover to survive through a Martian winter. Sol 5,000 will begin early Friday, Universal Time, with the 4,999th dawn a few hours later. Opportunity has worked actively right through the lowest-energy months of its eighth Martian winter.

Opportunity Rover (MER-B). Image Credits: NASA/JPL-Caltech

From the rover's perspective on the inside slope of the western rim of Endeavour Crater, the milestone sunrise will appear over the basin's eastern rim, about 14 miles (22 kilometers) away. Opportunity has driven over 28 miles (45 kilometers) from its landing site to its current location about one-third of the way down "Perseverance Valley," a shallow channel incised from the rim's crest of the crater's floor. The rover has returned about 225,000 images, all promptly made public online:

"We've reached lots of milestones, and this is one more," Callas said, "but more important than the numbers are the exploration and the scientific discoveries."

The mission made headlines during its first months with the evidence about groundwater and surface water environments on ancient Mars. Opportunity trekked to increasingly larger craters to look deeper into Mars and father back into Martian history, reaching Endeavour Crater in 2011. Researchers are now using the rover to investigate the processes that shaped Perseverance Valley.

For more about Opportunity's adventures and discoveries, see:

Images (mentioned), Text, Credits: NASA/Laurie Cantillo/Dwayne Brown/JPL/Guy Webster/Andrew Good.


jeudi 15 février 2018

Last NASA Communications Satellite of its Kind Joins Fleet

NASA - TDRS Mission logo.

Feb. 15, 2018

NASA has begun operating the last satellite of its kind in the network that provides communications and tracking services to more than 40 NASA missions, including critical, real-time communication with the International Space Station. Following its August launch and a five-month period of in-orbit testing, the third-generation Tracking and Data Relay Satellite (TDRS), referred to as TDRS-M until this important milestone, was renamed TDRS-13, becoming the tenth operational satellite in the geosynchronous, space-based fleet.

“With TDRS-13’s successful acceptance into the network, the fleet is fully replenished and set to continue carrying out its important mission through the mid-2020s,” said Badri Younes, NASA’s deputy associate administrator for Space Communications and Navigation at NASA Headquarters in Washington. “Now, we have begun focusing on the next generation of near-Earth communications relay capabilities.”

Image above: An artist concept of TDRS-M, now named TDRS-13. Image Credits: NASA's Goddard Space Flight Center.

The 10 TDRS spacecraft comprise the space-based portion of the Space Network, relaying signals from low-Earth-orbiting missions with nearly 100 percent coverage.

“The acceptance of this final third-generation TDRS into the Space Network is the result of many years of dedication and hard work by the TDRS team,” said Dave Littmann, the TDRS project manager at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “As a result, critical space communication and tracking services that enable NASA human spaceflight and scientific discovery will continue well into the next decade.”

​TDRS-13 launched on Aug. 18, 2017, aboard a United Launch Alliance Atlas V rocket from Cape Canaveral Air Force Station in Florida. Built by Boeing in El Segundo, California, TDRS-13 and its nearly identical third-generation sister spacecraft are performing well. TDRS-K and -L launched in 2013 and 2014, respectively.

NASA established the TDRS project in 1973, and the first satellite launched 10 years later, providing NASA an exponential increase in data rates and contact time communicating with the space shuttle and other orbiting spacecraft, such as the Hubble Space Telescope.  Since then, NASA has continued to expand the TDRS constellation and advance the spacecraft capabilities.

Image above: TDRS-M, now named TDRS-13, launched on Aug. 18, 2017, from Cape Canaveral Air Force Station in Florida. Following a period of in-orbit testing, the spacecraft has been accepted into NASA’s Space Network. Image Credits: NASA Kennedy/Tony Gray and Sandra Joseph.

“NASA looks forward to the future, developing even better ways to meet missions’ communications needs,” said Younes. “We will leverage NASA’s success in optical communications and other innovative technologies, as well as significantly increase our partnership with industry, as we envision a shift to increased reliance on commercial networks for most, if not all, of our communications needs in the near-Earth environment.”

Goddard is home to the TDRS project, which is responsible for the development and launch of these communication satellites. Boeing, headquartered in Chicago, Illinois, is the private contractor for the third-generation TDRS spacecraft. TDRS is the space element of NASA’s Space Network, providing the critical communication and navigation lifeline for NASA missions. NASA’s Space Communications and Navigation (SCaN) program, part of the Human Exploration and Operations Mission Directorate at the agency’s Headquarters in Washington, is responsible for NASA’s Space Network.

For more information about NASA’s TDRS satellites, visit:

For more information about SCaN, visit:

Space Network:

Images (mentioned), Text, Credits: NASA/Rob Garner/Goddard Space Flight Center, by Ashley Hume.