vendredi 15 septembre 2017

Hubble Catches Starbursts in a Barred Spiral Galaxy

NASA - Hubble Space Telescope patch.

Sept. 15, 2017

This Hubble Space Telescope picture shows NGC 5398, a barred spiral galaxy located about 55 million light-years away.

The galaxy is famous for containing an especially extensive HII region, a large cloud composed of ionized hydrogen (or HII, pronounced “H-two,” with H being the chemical symbol for hydrogen and the “II” indicating that the atoms have lost an electron to become ionized). NGC 5398’s cloud is named Tol 89 and sits at the lower left end of the galaxy’s central “bar” of stars, a structure that cuts through the galactic core and funnels material inwards to maintain the star formation occurring there.

Tol 86 is conspicuous in being the only large massive star-forming complex in the entire galaxy, with an extension of roughly 5,000 times; it contains at least seven young and massive star clusters. The two brightest clumps within Tol 89, which astronomers have named simply “A” and “B” appear to have undergone two bursts of star-forming activity — “starbursts” — roughly 4 million and less than 3 million years ago respectively. Tol 89-A is thought to contain a number of particularly bright and massive stars known as Wolf-Rayet stars, which are known for their high temperatures and extreme stellar winds.

 Hubble Space Telescope

For images and more information about Hubble, visit:

Image, Animation, Text, Credits: Credit: NASA/ESA/Text Credits: European Space Agency/NASA/Karl Hille.


Using Transparent Fish to Study Denser Bones

ISS - Medaka Osteoclast Mission patch.

Sept. 15, 2017

Astronauts have dealt with loss of bone density during space flight since space travel began. Recent research aboard the International Space Station looked at how osteoclasts, cells that normally break down bone tissue for normal replacement, influence this loss.

Image above: Flight Engineer Koichi Wakata works to activate the Multi-Purpose Small Payload Rack (MSPR) Hub unit and install the Medaka Chamber in the fluorescent microscope for observation of a Medaka sample. Image Credit: NASA.

Now a follow-up investigation, Medaka Osteoclast 2, examines the molecular mechanisms that develop osteoclasts, using live fish in space. These Medaka fish have translucent bodies and, for this investigation, a genetic modification that marked osteoblasts and osteoclasts with fluorescent proteins so that researchers can observe cellular and genetic changes during space flight.

Scientists sent similar fish to the space station in 2014 for live taping by Astronaut Koichi Wakata during the first use of a fluorescence microscope on an animal aboard the space station. The taping revealed enhanced signals of both osteoclasts and osteoblasts, cells that synthesize bone tissue, within two days of launch.

Image above: The JAXA Microscope in the Japanese Experiment Module. Image Credit: JAXA.

“We examined the fluorescent signals in living Medaka fish and surprisingly, observed up-regulation of osteoblast as well as osteoclast signals,” said principal investigator Akira Kudo, Tokyo Institute of Technology. Researchers saw enhanced intensity of the fluorescent signals in the entire body of the fish, but focused on the pharyngeal or jaw bone region, which has high bone turnover and high sensitivity to microgravity. “Osteoblasts and osteoclasts are most closely associated with bones and teeth. These mineralized tissues show the most sensitivity to gravity since they have the highest density of any tissue in the body.” 

Scientists also identified five specific genes related to how these cells respond to gravity, all five closely correlated with glucocorticoid receptors in mitochondria in the cell. Glucocorticoids are steroid hormones involved in glucose metabolism, and glucocorticoid receptors may play a part in osteoclast activation.

For the current investigation, astronauts will tape the Medaka fish live aboard the space station, allowing investigators to observe changes in fluorescent signals in real-time remotely from Tsukuba Space Center in Japan. Post-flight, the researchers will analyze changes in the microscopic anatomy and gene expression in the pharyngeal bone and jawbone of the fish.

Image above: A representation of how researchers on the ground conduct live-imaging under microgravity. Image Credit: Tokyo Institute of Technology.

Kudo, co-investigator Masahiro Chatani and colleagues recently published a paper in Nature Scientific Reports outlining the microgravity-induced changes observed in the gene expression levels of osteoblasts and osteoclasts in medaka jawbones. Evidence indicates that the basic molecular mechanism of osteoclasts is the same in mammals as in fish and that interaction with osteoblasts plays a crucial role.

“Initially we expected up-regulation of osteoclast signal only,” Kudo said. “Now, we know both osteoblasts and osteoclasts are activated under microgravity. That raises the question, what is the relationship between osteoblasts and osteoclasts under microgravity?”

Special Medaka chambers in KIBO, or the Japanese Experiment Module on the space station, make it possible to place the fish under a fluorescence microscope for live imaging. The Microscope Observation System consists of a microscope, power supply, and control unit. It is manipulated under the same measurement conditions in space and on the ground. An additional step to the experiment determined that the hypergravity experienced during launch into space had no detectable effect on fluorescent signals from the fish.

Image above: Observing bone metabolism under microgravity through increase of fluorescent signals of osteoblasts and osteoclasts in Medaka. Image Credits: Tokyo Institute of Technology/JAXA.

Results of this latest joint research by the Tokyo Institute of Technology and JAXA will clarify the molecular mechanism behind decreased bone mineral density in space. This will help scientists develop more effective ways to prevent bone density loss on future space missions. The results also may advance development of new drugs and treatments for people experiencing bone loss caused by bed rest, limited mobility, and age-related osteoporosis.

The next step, according to Kudo, is to find direct evidence that the glucocorticoid receptor and its signals in microgravity conditions are involved in bone loss during space flight. For that, more transparent fish may get to fly in space.

Related links:

Nature Scientific Reports:

Medaka Osteoclast 2:


Space Station Research and Technology:

International Space Station (ISS):

Images (mentioned), Text, Credits: NASA/Kristine Rainey/JSC/Melissa Gaskill.

Best regards,

Weekly Recap From the Expedition Lead Scientist, week of September 4, 2017

ISS - Expedition 53 Mission patch.

Sept. 15, 2017

(Highlights: Week of September 4, 2017) - Crew members on the International Space Station continued science investigations as they prepared the orbiting laboratory for three new residents, scheduled for launch to the station on Sept. 12.

Image above: Hurricane Irma as seen from the International Space Station over the Carribbean Sea and Florida. Image Credit: NASA.

Radiation detectors were recovered from around the interior of the station in support of the Radi-N2 Neutron Field Study (Radi-N2) investigation. The Canadian Space Agency's bubble spectrometers, placed in predetermined locations throughout the station, measure neutron radiation levels while ignoring all other radiation. This investigation characterizes the station neutron environment, defining the risk posed to crew members’ health, and provides the data necessary to develop advanced protective measures for future spaceflight. Because neutrons carry no electrical charge, they have greater potential to penetrate the body and damage tissue. Radi-N2 could help doctors better understand the connections between neutron radiation, DNA damage and mutation rates and can be applied to other radiation health issues on Earth.

Image above: NASA astronaut Randy Bresnik works on the Lung Tissue investigation inside the Microgravity Science Glovebox on the International Space Station. Image Credit: NASA.

Crew members also exchanged the filter on the Long Duration Sorbent Testbed (LDST), which scientists are using to create a more efficient life support system for long-duration, crewed space missions. A silica gel is currently used on the space station to remove humidity or water from the air, which allows life support hardware to more efficiently filter out carbon dioxide. The CO2 is processed with filtered hydrogen from the oxygen generator, converting the two waste products into water, a precious commodity in space.

Image above: The Miniature Exercise Device-2 before it is packed up for flight to the International Space Station. The small footprint of this system can help reduce the space needed and the extra weight of large exercise equipment for future long-duration missions. Image Credit: NASA.

After a year, that silica gel loses up to 75 percent of its capacity to absorb water, making it necessary to replace it. This investigation is studying 12 potential replacements for the gel to determine which would be most effective for use on long-duration missions. Data from the study will help determine the best material to use to build better filters, which would reduce the number of replacements sent on deep-space missions, leaving more cargo space available for other payloads. Ground crews will conduct a similar experiment in a laboratory on Earth using the same materials for comparison.

A new programmable exercise unit is being tested on the space station. The Miniature Exercise Device-2 (MED-2) is essentially a small programmable rowing system that can provide scientists and doctors with data on crew performance while also creating a program allowing precise control of the load. It can change resistance levels during any given session.

Space to Ground: Tracking a Monster: 09/08/2017

Video above: NASA's Space to Ground is a weekly update on what is happening on the International Space Station. Social media users can post with #spacetoground to ask questions or make a comment. Video Credit: NASA.

The microgravity environment of space weakens muscle and bone, which is why orbiting crew members spend a significant amount of time exercising. The MED-2 is a technology demonstration unit testing small robotic actuators that can provide motion and resistance for crew workout sessions. The size of the unit can help reduce the space needed and the weight of exercise equipment for future long-duration missions. This technology can also be used by patients undergoing physical therapy on Earth. The robotic actuator can be easily adjusted, customizing a rehabilitation program for a patient's individual needs.

Progress was made on other investigations this week, including: Functional Immune, Rodent Research-9, Lighting Effects, Lung Tissue, Fine Motor Skills, STaARS-iFUNGUS, SABL2, Genes in Space-4, Cool Flames Investigation, FIR LMM, and TReK.

Related links:

Radi-N2 Neutron Field Study (Radi-N2):

Long Duration Sorbent Testbed (LDST):

Miniature Exercise Device-2 (MED-2):

Functional Immune:

Rodent Research-9:

Lighting Effects:

Lung Tissue:

Fine Motor Skills:



Genes in Space-4:

Cool Flames Investigation:




Space Station Research and Technology:

International Space Station (ISS):

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

Best regards,

Array of Research Will Return to Earth Aboard Cargo Spacecraft Sunday

SpaceX - CRS-12 Dragon Mission patch.

Sept. 15, 2017

SpaceX's Dragon cargo spacecraft is scheduled to splash down in the Pacific Ocean on Sunday, Sept. 17, west of Baja California, with more than 3,800 pounds of NASA cargo, research experiments and technology demonstration samples from the International Space Station.

Image above: The SpaceX Dragon splashdown. Image Credits: SpaceX/NASA.

The Dragon spacecraft will be taken by ship to Long Beach, California, where some cargo will be removed immediately for return to NASA. Dragon then will be prepared for a return trip to SpaceX's test facility in McGregor, Texas, for final processing.

A variety of technological and biological studies are returning in Dragon. The Lung Tissue experiment used the microgravity environment of space to test strategies for growing new lung tissue. The ultimate goal of this investigation is to produce bioengineered human lung tissue that can be used as a predictive model of human responses allowing for the study of lung development, lung physiology or disease pathology.

Samples from the CASIS PCG 7 study used the orbiting laboratory’s microgravity environment to grow larger versions of an important protein implicated in Parkinson’s disease. Developed by the Michael J. Fox Foundation, Anatrace and Com-Pac International, researchers will look to take advantage of the station’s microgravity environment which allows protein crystals to grow larger and in more perfect shapes than earth-grown crystals, allowing them to be better analyzed on Earth. Defining the exact shape and morphology of LRRK2 would help scientists to better understand the pathology of Parkinson’s and aid in the development of therapies against this target.

Image above: The SpaceX Dragon will be detached from the Harmony module on Sunday and released for a splashdown into the Pacific Ocean. Image Credit: NASA.

Mice from NASA’s Rodent Research-9 study also will return live to Earth for additional study. The investigation combined three studies into one mission, with two looking at how microgravity affects blood vessels in the brain and in the eyes and the third looking at cartilage loss in hip and knee joints. For humans on Earth, research related to limited mobility and degrading joints can help scientists understand how arthritis develops, and a better understanding of the visual impairments experienced by astronauts can help identify causes and treatments for eye disorders.

Dragon currently is the only space station resupply spacecraft able to return a significant amount of cargo to Earth. The spacecraft lifted off from Launch Complex 39A at NASA's Kennedy Space Center in Florida on Aug. 14 carrying about 6,400 pounds of supplies and scientific cargo on the company’s twelfth commercial resupply mission to the station.

For more than 16 years, humans have lived and worked continuously aboard the International Space Station, advancing scientific knowledge and demonstrating new technologies, making research breakthroughs not possible on Earth that will enable long-duration human and robotic exploration into deep space. A global endeavor, more than 200 people from 18 countries have visited the unique microgravity laboratory that has hosted more than 2,100 research investigations from researchers in more than 95 countries.

Related links:

Lung Tissue experiment:

CASIS PCG 7 study:

Rodent Research-9 study:

Commercial Resupply:

Expedition 53:

Space Station Research and Technology:

International Space Station (ISS):

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


Galileos set to fly on Ariane 6

ESA - GALILEO Progamme logo.

15 September 2017

Four of the latest set of Galileo navigation satellites will be launched on Ariane 6 rockets – ESA’s first contract to use Europe’s new vehicle.

The launches are scheduled between the end of 2020 and mid-2021, using two Ariane 62 rockets – the configuration of Europe’s next-generation launch vehicle that is best suited to haul the two 750 kg navigation satellites into their orbits at 23 222 km altitude.

Under development, Ariane 6 is Europe’s newest launcher, designed to extend guaranteed access to space for Europe at a competitive price. It will operate in two configurations, depending on customer needs: Ariane 62 is fitted with two strap-on boosters while Ariane 64 has four.

 Twin-booster Ariane 6

“Ariane 6 is not only in full development, but it will soon be put to use,” notes Daniel Neuenschwander, ESA’s Director of Space Transportation. “This contract is a key step in the upcoming ramp-up phase of Ariane 6.”

The Galileos have so far either been launched in pairs by Soyuz from French Guiana or in fours by Ariane 5.

A new Ariane 5 flight is scheduled for the end of this year, to add four more satellites to the 18-strong constellation already in orbit. This month saw the arrival of the first elements of the rocket in French Guiana, transported aboard the MN Colibri roll-on/roll-off ship.

Galileo satellites

The contract specifies the decision to use Ariane 62 is subject to the vehicle’s development schedule, with Soyuz available as an alternative. A final choice will be made at the end of 2018, two years before the first launch.

Galileo is Europe’s own satellite navigation system, providing an array of positioning, navigation and timing services to Europe and the world.

A further eight Galileo ‘Batch 3’ satellites were ordered last June, to supplement the 26 built so far.

With 18 satellites now in orbit, Galileo began initial services on 15 December 2016, the first step towards full operations.

Ariane 6

Further launches will continue to build the constellation, which will gradually improve system performance and availability worldwide.

The launch contract with Arianespace was signed by Paul Verhoef, ESA’s Director of the Galileo Programme and Navigation-related Activities, and Stéphane Israel, Arianespace’s Chief Executive Officer. ESA signed the contract on behalf of the EU represented by the European Commission – Galileo’s owner. The Commission and ESA have a delegation agreement by which ESA acts as design and procurement agent on behalf of the Commission.

Ariane 6:

Another eight Galileo satellites for Europe:

Launching Galileo website:

European GNSS Agency:

Images. Video, Text, Credits: ESA/David Ducros/GSA.


Cassini Spacecraft Ends Its Historic Exploration of Saturn

NASA - Cassini Mission to Saturn patch.

September 15, 2017

Image above: Saturn's active, ocean-bearing moon Enceladus sinks behind the giant planet in a farewell portrait from NASA's Cassini spacecraft. Image Credits: NASA/JPL-Caltech/Space Science Institute.

A thrilling epoch in the exploration of our solar system came to a close today, as NASA's Cassini spacecraft made a fateful plunge into the atmosphere of Saturn, ending its 13-year tour of the ringed planet.

"This is the final chapter of an amazing mission, but it’s also a new beginning,” said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate at NASA Headquarters in Washington. “Cassini’s discovery of ocean worlds at Titan and Enceladus changed everything, shaking our views to the core about surprising places to search for potential life beyond Earth."

Telemetry received during the plunge indicates that, as expected, Cassini entered Saturn's atmosphere with its thrusters firing to maintain stability, as it sent back a unique final set of science observations. Loss of contact with the Cassini spacecraft occurred at 7:55 a.m. EDT (4:55 a.m. PDT), with the signal received by NASA's Deep Space Network antenna complex in Canberra, Australia.

Image above: last moments of the Cassini–Huygens mission as the spacecraft plunges into Saturn's atmosphere and burn. Image Credits: NASA/JLP-Caltech.

"It's a bittersweet, but fond, farewell to a mission that leaves behind an incredible wealth of discoveries that have changed our view of Saturn and our solar system, and will continue to shape future missions and research," said Michael Watkins, director of NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, which manages the Cassini mission for the agency. JPL also designed, developed and assembled the spacecraft.

Cassini's plunge brings to a close a series of 22 weekly "Grand Finale" dives between Saturn and its rings, a feat never before attempted by any spacecraft.

"The Cassini operations team did an absolutely stellar job guiding the spacecraft to its noble end," said Earl Maize, Cassini project manager at JPL. "From designing the trajectory seven years ago, to navigating through the 22 nail-biting plunges between Saturn and its rings, this is a crack shot group of scientists and engineers that scripted a fitting end to a great mission. What a way to go. Truly a blaze of glory."

As planned, data from eight of Cassini's science instruments was beamed back to Earth. Mission scientists will examine the spacecraft's final observations in the coming weeks for new insights about Saturn, including hints about the planet's formation and evolution, and processes occurring in its atmosphere.

"Things never will be quite the same for those of us on the Cassini team now that the spacecraft is no longer flying," said Linda Spilker, Cassini project scientist at JPL. "But, we take comfort knowing that every time we look up at Saturn in the night sky, part of Cassini will be there, too."

Image above: Earl Maize, program manager for NASA’s Cassini spacecraft at the agency’s Jet Propulsion Lab, and Julie Webster, spacecraft operations team manager for the Cassini mission at Saturn, embrace in an emotional moment for the entire Cassini team after the spacecraft plunged into Saturn, Friday, Sept. 15, 201. Image Credits: NASA/Joel Kowsky.

Cassini launched in 1997 from Cape Canaveral Air Force Station in Florida and arrived at Saturn in 2004. NASA extended its mission twice – first for two years, and then for seven more. The second mission extension provided dozens of flybys of the planet's icy moons, using the spacecraft's remaining rocket propellant along the way. Cassini finished its tour of the Saturn system with its Grand Finale, capped by Friday's intentional plunge into the planet to ensure Saturn's moons – particularly Enceladus, with its subsurface ocean and signs of hydrothermal activity – remain pristine for future exploration.

While the Cassini spacecraft is gone, its enormous collection of data about Saturn – the giant planet, its magnetosphere, rings and moons – will continue to yield new discoveries for decades to come.

Cassini's Last Looks at Saturn

Video above: In its final hours, NASA’s Cassini spacecraft returned these last looks at Saturn, its rings and moons, as it prepared to end its nearly 20-year voyage in space. This video includes the final image Cassini took, which shows the cloud tops where it would later plunge into the atmosphere. Video Credits: NASA/JPL. 

"Cassini may be gone, but its scientific bounty will keep us occupied for many years,” Spilker said. “We've only scratched the surface of what we can learn from the mountain of data it has sent back over its lifetime."

An online toolkit with information and resources for Cassini's Grand Finale is available at:

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. JPL, a division of Caltech in Pasadena, manages the mission for NASA's Science Mission Directorate in Washington.

For more information about the Cassini mission, visit

Cassini-Huygens: and

Images (mentioned), Video (mentioned), Text, Credits: NASA/Dwayne Brown/Laurie Cantillo/Karen Northon/JPL/Preston Dyches.

Best regards,

jeudi 14 septembre 2017

Expanded Crew Looks Ahead to Sunday Dragon Release

ISS - Expedition 53 Mission patch.

September 13, 2017

International Space Station (ISS). Animation Credit: NASA

Expedition 53 is fully staffed after two NASA astronauts and a Roscosmos cosmonaut completed a near six hour flight to the International Space Station overnight. Now the station residents will begin focusing their attention on the release of the SpaceX Dragon early Sunday.

Astronauts Joe Acaba and Mark Vande Hei and their Soyuz Commander Alexander Misurkin began a five-month mission aboard the station when their spacecraft hatch opened early Wednesday morning. The new trio joins Expedition 53 Commander Randy Bresnik and Flight Engineers Sergey Ryazanskiy of Roscosmos and Paolo Nespoli of the European Space Agency.

Image above: The SpaceX Dragon will be detached from the Harmony module on Sunday and released for a splashdown into the Pacific Ocean. Image Credit: NASA.

The SpaceX Dragon is being packed with science experiments and station gear for analysis back on Earth. Dragon will be robotically detached from the Harmony module and released for a splashdown and retrieval in the Pacific Ocean Sunday morning. NASA TV will cover the release activities beginning Sunday at 4:30 a.m. EDT.

Related links:

Expedition 53:

Space Station Research and Technology:

International Space Station (ISS):

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

Best regards,

Diet tracker in space

ISS - International Space Station logo.

14 September 2017

Whether you are on a diet or just want to be healthier, you might be one of those millions of people around the planet who use a mobile app to track everything you eat. The trend has arrived in space: European astronauts are now logging their meals on a tablet to make sure they are getting the right amount of nutrients.

An optimal diet, paired with constant exercise, is essential to counteract the effects of spaceflight on the human body. Bone loss, muscle atrophy and depleted nutrient stores such as protein, fat and vitamin D are among the negatives of space travel.

Thomas Pesquet

Research shows that energy intake in orbit is usually lower than on Earth – some even call it ‘spaceflight anorexia’. From tubes to cans and rehydratable packages, space food has evolved to meet nutritional requirements and boost crew morale.

“Food in space tastes different – it is like eating with a cold and a reduced appetite follows,” explains ESA astronaut Thomas Pesquet.

Since gaining weight is very unusual for astronauts, flight surgeons have always consulted astronauts when building their menus. Doctors want to ensure the crew are fuelling themselves with a balanced diet, suitable for space demands and the return to Earth. 

Astronaut food

Every meal on EveryWear

EveryWear is an iPad-based application that collects physiology and medical data from astronauts on the International Space Station. It is connected to wearable biomedical sensors that record exercise, heart rate and sleep quality.

Its main use is as a food diary. The astronaut simply scans the barcode of the food with the built-in tablet camera, classify it as breakfast, lunch dinner or snack, and add how water was consumed.

EveryWear app

“We wanted to move away from the old-fashioned questionnaires and snapping photos in orbit. It is cumbersome both for astronauts and the scientists on Earth,” says Brigitte Godard, ESA’s flight surgeon in charge of astronaut nutrition.

The crew can also add food by tapping on a specific product. The app comes loaded with a database containing all the food on the Space Station, both in English and in Russian. If something is not listed yet, there is an option to take a picture. 

Nutritional advice

An added value of the tool is that it connects the astronaut with nutrition experts on Earth, some 400 km below. Ground teams receive the information and can suggest the best combination of meals for a healthy stay in orbit.

In addition to the weekly expert advice, the app delivers automated nutrition reports for astronauts to monitor their daily intake and check the recommended dose. The focus is on calories, protein, water, carbohydrates, fat, sodium, calcium, iron and potassium.

Paolo with EveryWear

Thomas was the first to use EveryWear in orbit. Even though he was asked to use the app only for a week, he enthusiastically logged in more than 1200 food and drinks throughout his six-month mission.

“The app helped me be more conscious about what I was eating and improved my diet without taking up more time,” he says.

The science behind it

Brigitte highlights the advantages of this approach for science purposes: “It produces very reliable data because the number of food items is limited, the menu cycle is repetitive, and portion sizes and nutrient content are exact.” 

EveryWear was conceived in conjunction with France’s CNES space agency and the MEDES Institute for Space Physiology and Medicine for Thomas’ mission, but ESA astronaut Paolo Nespoli, currently in space, is also giving it a go.

Dinner in space

NASA has shown interest in using it to complement their results from standard blood and urine tests on the Space Station. The data will also help to optimise the amount of food needed for missions into deep space. 

Do you want to know more about the food eaten by astronauts in space? Check what’s on the space menu in our astronaut nutrition brochure:

Related links:


European space laboratory Columbus:

Where is the International Space Station?:

Connect with Paolo:

Connect with Thomas Pesquet:

Agenzia Spaziale Italiana:

International Space Station (ISS):

Images, Text, Credits: ESA/NASA


Venus' mysterious night side revealed

ESA - Venus Express Mission patch.

14 September 2017

Scientists have used ESA's Venus Express to characterise the wind and upper cloud patterns on the night side of Venus for the first time–with surprising results.

The study shows that atmosphere on Venus' night side behaves very differently to that on the side of the planet facing the Sun (the 'dayside'), exhibiting unexpected and previously-unseen cloud types, morphologies, and dynamics - some of which appear to be connected to features on the planet's surface.

Venus Express in orbit. Credit: ESA

"This is the first time we've been able to characterise how the atmosphere circulates on the night side of Venus on a global scale," says Javier Peralta of the Japan Aerospace Exploration Agency (JAXA), Japan, and lead author of the new study published in the journal Nature Astronomy. "While the atmospheric circulation on the planet's dayside has been extensively explored, there was still much to discover about the night side. We found that the cloud patterns there are different to those on the dayside, and influenced by Venus' topography."

Venus' atmosphere is dominated by strong winds that whirl around the planet far faster than Venus itself rotates. This phenomenon, known as 'super-rotation', sees Venusian winds rotating up to 60 times faster than the planet below, pushing and dragging along clouds within the atmosphere as they go. These clouds travel fastest at the upper cloud level, some 65 to 72 km above the surface.

"We've spent decades studying these super-rotating winds by tracking how the upper clouds move on Venus' dayside–these are clearly visible in images acquired in ultraviolet light," explains Peralta. "However, our models of Venus remain unable to reproduce this super-rotation, which clearly indicates that we might be missing some pieces of this puzzle.

Image above: Atmospheric super-rotation at the upper clouds of Venus. Image Credits: ESA, JAXA, J. Peralta and R. Hueso.

"We focused on the night side because it had been poorly explored; we can see the upper clouds on the planet's night side via their thermal emission, but it's been difficult to observe them properly because the contrast in our infrared images was too low to pick up enough detail."

The team used the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) on ESA's Venus Express spacecraft to observe the clouds in the infrared. "VIRTIS enabled us to see these clouds properly for the first time, allowing us to explore what previous teams could not–and we discovered unexpected and surprising results," adds Peralta.

Rather than capturing single images, VIRTIS gathered a 'cube' of hundreds of images of Venus acquired simultaneously at different wavelengths. This allowed the team to combine numerous images to improve the visibility of the clouds, and see them at unprecedented quality. The VIRTIS images thus reveal phenomena on Venus' night side that have never before been seen on the dayside.

Image above: Mysterious fast filaments in clouds on Venus. Image Credits: ESA, S. Naito, R. Hueso and J. Peralta.

The best models for how Venus' atmosphere behaves and circulates, known as Global Circulation Models (GCMs), predict super-rotation to occur in much the same way on Venus' night side as on its dayside. However, this research by Peralta and his colleagues contradicts these models.

Instead, the super-rotation seems to be more irregular and chaotic on the night side.

Night side upper clouds form different shapes and morphologies than those found elsewhere–large, wavy, patchy, irregular, and filament-like patterns, many of which are unseen in dayside images–and are dominated by unmoving phenomena known as stationary waves.

Stationary waves in clouds on Venus. Credit: ESA/VIRTIS/J. Peralta and R. Hueso

"Stationary waves are probably what we'd call gravity waves–in other words, rising waves generated lower in Venus' atmosphere that appear not to move with the planet's rotation," says co-author Agustin Sánchez-Lavega of University del País Vasco in Bilbao, Spain. "These waves are concentrated over steep, mountainous areas of Venus; this suggests that the planet's topography is affecting what happens way up above in the clouds."

Stationary waves in clouds on Venus. Credit: ESA/VIRTIS/J. Peralta and R. Hueso

The 3D properties of these stationary waves were also obtained by combining VIRTIS data with radio-science data from the Venus Radio Science experiment, or VeRa, also on Venus Express.

A link between atmospheric motion and topography has been spied on Venus before, although on the dayside; in a study from last year, researchers found weather patterns and rising waves on the dayside of Venus to be directly connected to topographic features on the surface.

"It was an exciting moment when we realised that some of the cloud features in the VIRTIS images didn't move along with the atmosphere," says Peralta. "We had a long debate about whether the results were real–until we realised that another team, led by co-author Dr. Kouyama, had also independently discovered stationary clouds on the night side using NASA's Infrared Telescope Facility (IRTF) in Hawaii! Our findings were confirmed when JAXA's Akatsuki spacecraft was inserted into orbit around Venus and immediately spotted the biggest stationary wave ever observed in the Solar System on Venus' dayside."

Image above: New types of cloud morphology on Venus. Image Credits: ESA, NASA, J. Peralta and R. Hueso.

This finding raises challenges for existing models of stationary waves. Such waves were expected to be formed by surface winds interacting with obstacles such as surface elevations–a mountain, for example. However, previous Russian missions involving landers have measured surface winds on Venus that may be too weak for this to be true.

Additionally, the planet's southern hemisphere (where VIRTIS observed) is generally quite low in elevation, and–more mysteriously–stationary waves appear to be missing in Venus' intermediate and lower cloud levels (up to roughly 50 km above the surface).

"We expected to find these waves in the lower levels because we see them in the upper levels, and we thought that they rose up through the cloud from the surface," says co-author Ricardo Hueso of University of the Basque Country in Bilbao, Spain. "It's an unexpected result for sure, and we'll all need to revisit our models of Venus to explore its meaning."

The effect of topography on atmospheric circulation remains unclear among climate modellers; many models show that the inclusion or omission of surface topography makes a difference to the resulting behaviour seen in Venus' atmosphere, but do not show persistent weather patterns linked to topography.

"This study challenges our current understanding of climate modelling and, specifically, the super-rotation, which is a key phenomenon seen at Venus," says Håkan Svedhem, ESA Project Scientist for Venus Express. "Additionally, it demonstrates the power of combining data from multiple different sources–in this case, remote sensing and radio-science data from Venus Express' VIRTIS and VeRa, complemented by ground-based observations from IRTF's SpeX. This is a significant result for VIRTIS and for Venus Express, and is very important for our knowledge of Venus as a whole."

Notes for editors:

This research is reported in 'Stationary waves and slowly moving features in the night upper clouds of Venus', by J. Peralta et al., published on 24 July 2017 in Nature Astronomy. doi: 10.1038/s41550-017-0187.

Akatsuki's discovery of a large stationary wave on the dayside of Venus is described in a paper ('Large stationary gravity wave in the atmosphere of Venus') by T. Fukuhara et al., published in the journal Nature Geoscience in January 2017. doi:10.1038/ngeo2873.

Co-author T. Kouyama of the National Institute of Advanced Industrial Science and Technology in Tokyo, Japan, independently observed the stationary waves described in this work in observations from NASA's Infrared Telescope Facility (IRTF) in Hawaii, USA.

The measurements were conducted by the Venus Express Visible and Infrared Thermal Imaging Spectrometer-Mapper (VIRTIS) and the Venus Express Venus Radio Science experiment (VeRa), for which Giuseppe Piccioni (INAF-IAPS; Rome, Italy) and Martin Pätzold (University of Cologne; Cologne, Germany) are the respective PIs. Additional observations were made by the Medium-Resolution 0.8-5.5 Micron Spectrograph and Imager at NASA's Infrared Telescope Facility (IRTF).

ESA's Venus Express launched in 2005 and entered orbit around Venus in 2006; the mission ended in December 2014. During its years of operation the spacecraft and its payload gathered a wealth of information about our sister planet. More information on the mission is available here:

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Nature Astronomy:

Images (mentioned), Animations (mentioned), Text, Credits: ESA/Håkan Svedhem/University of the Basque Country Bilbao/Ricardo Hueso/Agustin Sánchez-Lavega/ISAS/JAXA/Javier Peralta.

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NASA’s Robotic ‘Sniffer’ Confirms Space Station Leak, Repair

ISS - International Space Station patch.

Sept. 14, 2017

In recent operations on the International Space Station, robotic operators were twice able to test and confirm the ability of the Robotic External Leak Locator (RELL) to “smell” in space. 

Using the RELL instruments, operators successfully located a small leak from the station’s ammonia coolant loop, and confirmed that it was not a safety concern. Later they were able to return and more precisely characterize the leak. This valuable data helped station operators vent and isolate the leaking line from the coolant loop and successfully stop the leak.

Image above: The Robotic External Leak Locator on the end of the Dextre robot in February 2017. Image Credit: NASA.

“By locating and monitoring this ammonia leak, RELL verified station’s safety status and avoided a risky spacewalk to find the leak,” said Adam Naids, RELL project manager at NASA’s Johnson Space Center in Houston. “RELL performed spectacularly and successfully carried out the job it was built to do.”

RELL was launched to the space station aboard a Orbital ATK resupply mission in 2015. It was stowed aboard the space station for several months before NASA astronaut Kate Rubins loaded it onto the Japanese Experiment Module slide table. The slide table was extended into space where robotic operators from NASA Johnson controlled the Dextre robot to grab RELL and run it through initial testing. Engineers on the ground verified RELL was functioning properly and effectively communicating back to Johnson.

RELL’s instruments provide directionally sensitive measurements of the amount and kind of gases present. By taking samples, RELL established baseline readings for amounts and kinds of gases which are normally present outside the station. These baseline readings matched what engineers expected, but RELL detected an ammonia signature during the final portion of testing.

Operators were able to identify the ammonia source, an isolation valve for the ammonia cooling loop on the station. Robot operators maneuvered Dextre to position RELL within 12 inches of the leak to collect measurements for several days. With the data gathered, personnel on the ground were able to determine the leak posed no risk to the station or astronauts on board.

Image above: Astronaut Kate Rubins loading the Robotic External Leak Locator for deployment into space. Image Credit: NASA.

Later, ground controllers returned RELL to take high resolution scans from a variety of angles to identify the specific location of the leak. Assisted by RELL’s precise data, station managers choreographed a spacewalk which saw astronauts perform tests to gather additional data that would inform a plan to solve the leak issue. Afterwards, station operators successfully vented and isolated the leaking hose connection from the rest of the cooling system. The station team was able to confirm the leak had stopped and the ammonia coolant loop was intact.

To date, RELL has logged nearly 190 total hours in space, completed thousands of scans, and continuously demonstrated its value aboard the space station. RELL is currently inside station, ready to return outside when needed.

“Robotic tools apply to many areas of space exploration,” said Benjamin Reed, deputy division director for the Satellite Servicing Projects Division (SSPD) at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “RELL is at the forefront of the great work being done with robotic tools on space station, and we couldn’t be more pleased with its successes.”

RELL is a collaboration between the Engineering Directorate at Johnson and SSPD at Goddard.

Related links:


Living in Space:

NASA’s Johnson Space Center:

NASA’s Goddard Space Flight Center:

International Space Station (ISS):

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


Hubble observes pitch black planet

ESA - Hubble Space Telescope logo.

14 September 2017

Astronomers have discovered that the well-studied exoplanet WASP-12b reflects almost no light, making it appear essentially pitch black. This discovery sheds new light on the atmospheric composition of the planet and also refutes previous hypotheses about WASP-12b’s atmosphere. The results are also in stark contrast to observations of another similarly sized exoplanet.

The Pitch-Black Exoplanet WASP-12b

Using the Space Telescope Imaging Spectrograph (STIS) on the NASA/ESA Hubble Space Telescope, an international team led by astronomers at McGill University, Canada, and the University of Exeter, UK, have measured how much light the exoplanet WASP-12b reflects — its albedo — in order to learn more about the composition of its atmosphere [1].

The results were surprising, explains lead author Taylor Bell, a Master’s student in astronomy at McGill University who is affiliated with the Institute for Research on Exoplanets: “The measured albedo of WASP-12b is 0.064 at most. This is an extremely low value, making the planet darker than fresh asphalt!” This makes WASP-12b two times less reflective than our Moon which has an albedo of 0.12 [2]. Bell adds: “The low albedo shows we still have a lot to learn about WASP-12b and other similar exoplanets.”

WASP-12b orbits the Sun-like star WASP-12A, about 1400 light-years away, and since its discovery in 2008 it has become one of the best studied exoplanets (opo1354, opo1015, opo1436, heic1524). With a radius almost twice that of Jupiter and a year of just over one Earth day, WASP-12b is categorised as a hot Jupiter. Because it is so close to its parent star, the gravitational pull of the star has stretched WASP-12b into an egg shape and raised the surface temperature of its daylight side to 2600 degrees Celsius.

The high temperature is also the most likely explanation for WASP-12b’s low albedo. “There are other hot Jupiters that have been found to be remarkably black, but they are much cooler than WASP-12b. For those planets, it is suggested that things like clouds and alkali metals are the reason for the absorption of light, but those don’t work for WASP-12b because it is so incredibly hot," explains Bell.

The daylight side of WASP-12b is so hot that clouds cannot form and alkali metals are ionised. It is even hot enough to break up hydrogen molecules into atomic hydrogen which causes the atmosphere to act more like the atmosphere of a low-mass star than like a planetary atmosphere. This leads to the low albedo of the exoplanet.

To measure the albedo of WASP-12b the scientists observed the exoplanet in October 2016 during an eclipse, when the planet was near full phase and passed behind its host star for a time. This is the best method to determine the albedo of an exoplanet, as it involves directly measuring the amount of light being reflected. However, this technique requires a precision ten times greater than traditional transit observations. Using Hubble’s Space Telescope Imaging Spectrograph the scientists were able to measure the albedo of WASP-12b at several different wavelengths.

“After we measured the albedo we compared it to spectral models of previously suggested atmospheric models of WASP-12b”, explains Nikolay Nikolov (University of Exeter, UK), co-author of the study. “We found that the data match neither of the two currently proposed models.” [3]. The new data indicate that the WASP-12b atmosphere is composed of atomic hydrogen and helium.

Hubble Space Telescope

WASP-12b is only the second planet to have spectrally resolved albedo measurements, the first being HD 189733b, another hot Jupiter. The data gathered by Bell and his team allowed them to determine whether the planet reflects more light towards the blue or the red end of the spectrum. While the results for HD 189733b suggest that the exoplanet has a deep blue colour (heic1312), WASP-12b, on the other hand, is not reflecting light at any wavelength. WASP-12b does, however, emit light because of its high temperature, giving it a red hue similar to a hot glowing metal.

“The fact that the first two exoplanets with measured spectral albedo exhibit significant differences demonstrates the importance of these types of spectral observations and highlights the great diversity among hot Jupiters,” concludes Bell.


[1] The team measured the optical geometric albedo of WASP-12b, which measures the light that is scattered back towards the source of light, and can have values above 1. This is in contrast to the Bond albedo, which describes the total amount of energy reflected across all wavelengths and always falls in the range of 0 to 1.

[2] Earth has an average optical geometric albedo of about 0.37. Enceladus, an icy moon of Saturn, has an albedo of 1.4, the highest known albedo of any celestial body in the Solar System.

[3] One proposed model was an aluminum-oxide atmosphere with Mie scattering while the other was a cloud-free atmosphere with Rayleigh scattering.

More information:

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

The international team of astronomers in this study consists of T. J. Bell (McGill University, Canada), N. Nikolov (University of Exeter, UK), N. B. Cowan (McGill University, Canada), J. K. Barstow (University College London, UK), T. S. Barman (University of Arizona, USA), I. J. M. Crossfield (University of California Santa Cruz, USA; Sagan Fellow), N. P. Gibson (Queen’s University Belfast, UK), T. M. Evans (University of Exeter, UK), D. K. Sing (University of Exeter, UK), H. A. Knuston (California Institute of Technology, USA), T. Kataria (Jet Propulsion Laboratory, USA), J. D. Lothringer (University of Arizona, USA), B. Benneke (Université de Montréal, Canada), and J. C. Schwartz (McGill University, USA).


ESA's Hubble site:






Images of Hubble:

Hubblesite release:

Science paper:

Space Telescope Imaging Spectrograph (STIS):

Institute for Research on Exoplanets:

Image, Animation, Credits: NASA, ESA, and G. Bacon (STScI).


NASA's Curiosity Mars Rover Climbing Toward Ridge Top

NASA - Mars Science Laboratory (MSL) patch.

September 14, 2017

(Click on the image for enlarge)

Image above: Researchers used the Mastcam on NASA's Curiosity Mars rover to gain this detailed view of layers in "Vera Rubin Ridge" from just below the ridge. Image Credits: NASA/JPL-Caltech/MSSS.

NASA's Mars rover Curiosity has begun the steep ascent of an iron-oxide-bearing ridge that's grabbed scientists' attention since before the car-sized rover's 2012 landing.

"We're on the climb now, driving up a route where we can access the layers we've studied from below," said Abigail Fraeman, a Curiosity science-team member at NASA's Jet Propulsion Laboratory in Pasadena, California.

"Vera Rubin Ridge" stands prominently on the northwestern flank of Mount Sharp, resisting erosion better than the less-steep portions of the mountain below and above it. The ridge, also called "Hematite Ridge," was informally named earlier this year in honor of pioneering astrophysicist Vera Rubin.

(Click on the image for enlarge)

Image above: "Vera Rubin Ridge," a favored destination for NASA's Curiosity Mars rover even before the rover landed in 2012, rises near the rover nearly five years later in this panorama from Curiosity's Mastcam. Image Credits: NASA/JPL-Caltech/MSSS.

"As we skirted around the base of the ridge this summer, we had the opportunity to observe the large vertical exposure of rock layers that make up the bottom part of the ridge," said Fraeman, who organized the rover's ridge campaign. "But even though steep cliffs are great for exposing the stratifications, they're not so good for driving up."

The ascent to the top of the ridge from a transition in rock-layer appearance at the bottom of it will gain about 213 feet (65 meters) of elevation -- about 20 stories. The climb requires a series of drives totaling a little more than a third of a mile (570 meters). Before starting this ascent in early September, Curiosity had gained a total of about 980 feet (about 300 meters) in elevation in drives totaling 10.76 miles (17.32 kilometers) from its landing site to the base of the ridge.

(Click on the image for enlarge)

Image above: The Mastcam on NASA's Curiosity Mars rover captured this view of "Vera Rubin Ridge" about two weeks before the rover starting to ascend this steep ridge on lower Mount Sharp. Image Credits: NASA/JPL-Caltech/MSSS.

Curiosity's telephoto observations of the ridge from just beneath it show finer layering, with extensive bright veins of varying widths cutting through the layers.

"Now we'll have a chance to examine the layers up close as the rover climbs," Fraeman said.

Curiosity Project Scientist Ashwin Vasavada of JPL said, "Using data from orbiters and our own approach imaging, the team has chosen places to pause for more extensive studies on the way up, such as where the rock layers show changes in appearance or composition. But the campaign plan will evolve as we examine the rocks in detail. As always, it's a mix of planning and discovery."

Image above: This view of "Vera Rubin Ridge" from the ChemCam instrument on NASA's Curiosity Mars rover shows sedimentary layers and fracture-filling mineral deposits. Image Credits: NASA/JPL-Caltech/CNES/CNRS/LANL/IRAP/IAS/LPGN.

In orbital spectrometer observations, the iron-oxide mineral hematite shows up more strongly at the ridge top than elsewhere on lower Mount Sharp, including locations where Curiosity has already found hematite. Researchers seek to gain better understanding about why the ridge resists erosion, what concentrated its hematite, whether those factors are related, and what the rocks of the ridge can reveal about ancient Martian environmental conditions.

"The team is excited to be exploring Vera Rubin Ridge, as this hematite ridge has been a go-to target for Curiosity ever since Gale Crater was selected as the landing site," said Michael Meyer, lead scientist of NASA's Mars Exploration Program at the agency's Washington headquarters.

Image above: This view of "Vera Rubin Ridge" from the ChemCam instrument on NASA's Curiosity Mars rover shows sedimentary layers, mineral veins and effects of wind erosion. Image Credits: NASA/JPL-Caltech/CNES/CNRS/LANL/IRAP/IAS/LPGN.

During the first year after its landing near the base of Mount Sharp, the Curiosity mission accomplished a major goal by determining that billions of years ago, a Martian lake offered conditions that would have been favorable for microbial life. Curiosity has since traversed through a diversity of environments where both water and wind have left their imprint. Vera Rubin Ridge and layers above it that contain clay and sulfate minerals provide tempting opportunities to learn even more about the history and habitability of ancient Mars.

For more about Curiosity, visit:

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