samedi 25 mars 2017

CryoSat reveals Antarctica in 3D

ESA - CRYOSAT Mission logo.

25 March 2017

Around 250 million measurements taken by ESA’s CryoSat over the last six years have been used to create a unique 3D view of Antarctica, offering a snapshot of the undulating surface of this vast ice sheet.

Antarctica in 3D

CryoSat’s radar altimeter detects tiny variations in the height of the ice across the entire continent, including on the steeper continental margins where the vast majority of ice losses occur.

Importantly, the satellite’s orbit takes it to latitudes within 200 km of the north and south poles – closer than other Earth observation satellites.

Naturally, the mission is also used to map changes in the thickness of ice floating in the polar oceans, which is particularly important for the Arctic.

This new ‘digital elevation model’ was revealed at this week’s gathering of CryoSat scientists in Banff, Canada.

Tom Slater, researcher at the UK Centre for Polar Observation and Modelling (CPOM), said, “We used around 250 million measurements taken by CryoSat between 2010 and 2016 to create the most comprehensive picture of Antarctic ice elevation currently available.”

It offers wide range of applications – showing the surface of Antarctica in such detail means it can be used in anything from planning fieldwork to modelling the ice sheet. 

Ice height

It also allows scientists to distinguish between changes in topography and ice motion when working with other satellite measurements, such as those used to calculate the balance between how much the ice sheet is gaining by accumulating snow and losing through melting and creating icebergs.

The model will soon be freely available via the CPOM portal, which already provides information on sea-ice volume and thickness, ice velocity and, shortly, ice sheets. In the meantime, however, the model can be downloaded here:

CPOM Director Andrew Shepherd added, “We want the digital elevation model to be accessible to anyone who uses ice-sheet surface topography measurements in their work.

“This should benefit not only studies of the Antarctic ice sheet, but also projections of future sea-level rise.”

ESA's ice mission

ESA’s CryoSat mission manager, Tommaso Parrinello, said, “We are hearing some great results from our mission at the meeting here in Banff.

“It’s now widely recognised that dwindling polar ice is one of the first casualties of climate change, but it’s important to provide the hard facts – and this we can do with CryoSat.

“It’s equally important to make sure the satellite’s data are correct and so we have a huge international field campaign just started in the Arctic to take ‘ground  truth’ measurements from aircraft and on the ice to compare with those of CryoSat. It’s a tough environment – so we wish them lots of luck.”

Related links:

Antarctica digital elevation model:


Access CryoSat data:

CryoSat Science Meeting:

Centre for Polar Observation and Modelling:

CPOM data portal:

Natural Environment Research Council:

Images, Text, Credits: ESA/CPOM/AOES Medialab.

Best regards,

vendredi 24 mars 2017

Weekly Recap From the Expedition Lead Scientist, week of March 13, 2017

ISS - Expedition 50 Mission patch.

March 24, 2017

(Highlights: Week of March 13, 2017) - Crew members on the International Space Station worked on a pair of investigations into water that could result in cleaner water on Earth.

Image above: This long-exposure image captures a pair of Russian Soyuz capsules attached to the International Space Station as the outpost flies over the night lights of Earth at 17,500 mph. Image Credit: NASA.

ESA (European Space Agency) astronaut Thomas Pesquet sampled filtered water on the space station as part of the Water Monitoring Suite experiment. This new technology can quickly detect and identify potentially harmful microorganisms in the station's water supply. If successful, it will ensure that crew members can perform real time tests and monitor the safety of their water on future missions.

Using current technology, it can take a week to search for harmful bacteria. With the Water Monitoring Suite – part of the Microbial Monitoring System on the station – it could take less than an hour. This would be invaluable to travelers in space where water is a very limited and precious commodity, and could also help millions of people on Earth who do not have access to clean water. Equipment that is fast and simple to use can improve water quality monitoring in remote areas.

Image above: NASA astronaut Shane Kimbrough loads organic samples into the Minus Eighty Degree Laboratory Freezer for ISS (MEFLI) in preparation of sending them back to Earth on the SpaceX 10 Dragon capsule. Image Credit: NASA.

Pesquet worked on a separate investigation into clean water on the station, injecting water into a pair of Aquapads and leaving them to incubate at ambient temperature inside the orbiting laboratory. After two days, he took photographs of the resulting bacterial contamination in the cotton-based petri dish.

The water astronauts drink on the station is recycled by up to 80 percent from their sweat, urine, and other reclaimed wastewater sources. Recycling water reduces the number of supply missions needed to run the station, and building a self-sufficient spacecraft is necessary for future missions traveling farther from our planet. Using a device that consists of a simple absorbent cotton -- injected with 1 milliliter of water -- and a tablet computer application, ESA’s Aquapad aims to improve the speed and efficiency of water tests in orbit. This quick and simple analysis of water could also help test drinking water on Earth in countries where access to safe water to drink is a constant problem. Aquapad could also be used to diagnose the state of the water after natural disasters.

Pesquet packed samples of the study of gravity-controlled growth and development in plants using true microgravity conditions (Auxin Transport) for delivery back to Earth on the SpaceX 10 Dragon capsule. The JAXA (Japan Aerospace Exploration Agency) investigation seeks new insight into how gravity – or the lack of it – affects plant development. The study focuses on auxins – a plant hormone discovered by observing how plants respond to light.

Image above: ESA astronaut Thomas Pesquet initiated the ESA-sponsored Aquapad technology demonstration and sampling using the Microbial Monitoring System (MMS) portion of the Water Monitoring Suite (WMS) experiment. Image Credit: NASA.

Scientists will study the role auxins play in pea and corn seedlings grown in microgravity. Future space travelers will require plant and oxygen production during long space missions and scientists need to understand how to grow plants in microgravity, where there is no clear distinction between up and down. This investigation develops new techniques for controlling plant growth direction by using plant hormones, including auxins, involved in plant development. Results may provide new techniques for efficiently growing and watering seedlings in microgravity, benefiting future life sciences investigations as well as plant cultivation in space. This research can also provide additional insight on how to utilize plants to provide more suitable and comfortable environmental conditions on Earth.

Human research investigations conducted this week include At Home in Space, Fine Motor Skills, Energy, Habitability, Space Headaches, and Dose Tracker.

Progress was made on other investigations, outreach activities, and facilities this week, including APEX-4, CASIS PCG 5, Tangolab-1, Simple Solar Neutron Detector, Google Street View, Meteor, Tropical Cyclone, Microgravity Expanded Stem Cells, Rodent Research-4, ISS Ham Radio, Group Combustion, SODI-DCMIX #3, Multi-Gas Monitor, MAGVECTOR, BEAM, Radi-N2, Manufacturing Device, ExHAM #2 and NanoRacks Science Box, NanoRacks Modules 9 & 71.

Related links:

Water Monitoring Suite:


Auxin Transport:

At Home in Space:

Fine Motor Skills:



Space Headaches:

Dose Tracker:




Tropical Cyclone:

Microgravity Expanded Stem Cells:

Rodent Research-4:

ISS Ham Radio:

Group Combustion:


Multi-Gas Monitor:




Space Station Research and Technology:

International Space Station (ISS):

Images (mentioned), Text, Credits: NASA/Kristine Rainey/Jorge Sotomayor, Lead Increment Scientist Expeditions 49 & 50.

Best regards,

Extending Science in the Search for the Origin of the Cosmos

ISS - AMS-02 Mission patch.

March 24, 2017

Attached to the outside of the International Space Station, the Alpha Magnetic Spectrometer (AMS) is circling Earth and sifting through cosmic ray particles traveling in the universe. Hundreds of scientists from 16 countries are analyzing the data, hoping to determine what the universe is made of and how it began, looking for clues on the origin of dark matter, invisible matter that can't be directly detected but can be inferred, and the existence of antimatter, made of elementary particles with the opposite charge of ordinary matter, which scientists have rarely been able to observe.

AMS is composed of a magnet and several detectors that provide the scientists on the ground with information about the particles. The magnetic field produced by the magnet bends the trajectory of the electrically-charged cosmic ray particles already traveling in the space station’s path, thereby identifying the sign of the particle’s charge. AMS records the number of particles that pass through its detectors; the kinds of particles passing, characteristics such as particle charge, the sign of the charge (positive or negative), mass and velocity; and which direction they came from so that scientists can attempt to track down their source. All of the information is collected using 300,000 data channels in the nanoseconds it takes a particle to travel through AMS, and then sent down to scientists on the ground for analysis.

The more particles AMS is able collect, the more scientists will be able to strengthen their findings. Launched in 2011, AMS was originally designed to operate for the duration of a three year mission, and has already surpassed that expectation. With the extension of the station through 2024, engineers are currently assessing long-term plans to extend the life of AMS to collect data throughout the lifetime of the station.

 Alpha Magnetic Spectrometer (AMS) on International Space Station (ISS)

Having exceeded the original three-year lifespan, some components are beginning to show wear. In particular, the thermal control system for one of the detectors, called the Silicon Tracker, has shown degradation. The system includes four redundant cooling pumps, only one of which is required to operate at given time. One of the pumps stopped functioning in March 2014, and another pump was found to have degraded as well, leading engineers on the ground to switch to one of two remaining pumps by the end of 2014 to continue collecting science data. A thermal cover was added during a spacewalk in 2015, and engineers switched to the last fully functional pump in March 2017 after the third pump showed similar signs of degradation.

A functioning thermal control system is required to support the silicon tracker, and data from the silicon tracker is needed in combination with the data from the other trackers to support the AMS research. The other components of AMS appear to be in good shape, and long-term planning is underway to evaluate the potential to bypass the pumps and associated equipment for this tracker with an upgraded system put in place during a series of spacewalks.

Close to 100 billion cosmic rays with energies up to multi trillion electron volts have been analyzed by AMS. Results to date have already challenged our understanding of the origin of cosmic ray particles and how they travel through the universe. For example, researchers have found an excess of high-energy positron particles, which are the anti-particle opposite to the common electron. The excess of positrons might be from a source we are familiar with, such as a pulsar, but they could also be produced by collisions of particles of dark matter. With additional data, enabled by extending the life of AMS, scientist may be able to determine the rate at which they decrease, shedding light on a possible cause. To provide further insight, AMS scientists are also analyzing high-energy antiprotons, which pulsars do not produce and may be a unique signature of dark matter.

AMS is a joint effort between NASA and the Department of Energy’s Office of Science and is led by Principal Investigator Samuel Ting, a Nobel laureate from the Massachusetts Institute of Technology.  The AMS team includes some 600 physicists from 56 institutions in 16 countries from Europe, North America and Asia. The contributions from the various participants were integrated when the AMS was built at the European Organization for Nuclear Research (CERN) outside of Geneva, Switzerland.

Alpha Magnetic Spectrometer (AMS):

International Space Station (ISS):

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

Image (mentioned), Text, Credits: NASA/Kathryn Hambleton.


Spacewalkers Successfully Complete Primary Tasks

ISS - Expedition 50 Mission patch / EVA - Extra Vehicular Activities patch.

March 24, 2017

Expedition 50 Commander Shane Kimbrough of NASA and Flight Engineer Thomas Pesquet of ESA (European Space Agency concluded their spacewalk at 1:58 p.m. EDT. During the spacewalk, which lasted just over six-and-a-half hours, the two astronauts successfully disconnected cables and electrical connections on the Pressurized Mating Adapter-3 to prepare for its robotic move Sunday, March 26.

The PMA-3 provides the pressurized interface between the station modules and the International Docking Adapter, which will accommodate commercial crew vehicle dockings.

Image above: Spacewalkers Thomas Pesquet (left) and Shane Kimbrough meet at the Quest airlock to begin wrapping up their successful spacewalk. Image Credit: NASA TV.

The astronauts also lubricated the latching end effector on the Special Purpose Dexterous Manipulator “extension” for the Canadarm2 robotic arm, inspected a radiator valve and replaced cameras on the Japanese segment of the outpost.

A second spacewalk has been rescheduled to Thursday, March 30, and a third spacewalk now is targeted for Thursday, April 6.

The second spacewalk will feature Kimbrough and Flight Engineer Peggy Whitson of NASA reconnecting cables and electrical connections on PMA-3 at its new home on top Harmony. They also will install the second of the two upgraded computer relay boxes on the station’s truss and install shields and covers on PMA-3 and the now-vacant common berthing mechanism port on Tranquility.

Space Station Crew Members Walk in Space with an Eye to the Future

The plan for the final spacewalk is for Whitson and Pesquet to replace an avionics box on the starboard truss called an ExPRESS Logistics Carrier, a storage platform. The box houses electrical and command and data routing equipment for the science experiments and replacement hardware stored outside of the station. The new avionics box is scheduled to launch on the upcoming Orbital ATK Cygnus cargo spacecraft mission.

Spacewalkers have now spent a total of 1,236 hours and 38 minutes working outside the station during 198 spacewalks in support of assembly and maintenance of the orbiting laboratory.

Related links:

International Docking Adapter:


Space Station Research and Technology:

International Space Station (ISS):

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

Best regards,

NASA’s Juno Spacecraft Set for Fifth Jupiter Flyby

NASA - JUNO Mission logo.

March 24, 2017

Image above: This enhanced-color image of a mysterious dark spot on Jupiter seems to reveal a Jovian “galaxy” of swirling storms. Image Credits: NASA/JPL-Caltech/SwRI/MSSS/Roman Tkachenko.

NASA's Juno spacecraft will make its fifth flyby over Jupiter's mysterious cloud tops on Monday, March 27, at 1:52 a.m. PDT (4:52 a.m. EDT, 8:52 UTC).

At the time of closest approach (called perijove), Juno will be about 2,700 miles (4,400 kilometers) above the planet's cloud tops, traveling at a speed of about 129,000 miles per hour (57.8 kilometers per second) relative to the gas-giant planet. All of Juno's eight science instruments will be on and collecting data during the flyby.

"This will be our fourth science pass -- the fifth close flyby of Jupiter of the mission -- and we are excited to see what new discoveries Juno will reveal,” said Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio. "Every time we get near Jupiter’s cloud tops, we learn new insights that help us understand this amazing giant planet."

The Juno science team continues to analyze returns from previous flybys. Scientists have discovered that Jupiter's magnetic fields are more complicated than originally thought, and that the belts and zones that give the planet's cloud tops their distinctive look extend deep into the its interior. Observations of the energetic particles that create the incandescent auroras suggest a complicated current system involving charged material lofted from volcanoes on Jupiter's moon Io.

Peer-reviewed papers with more in-depth science results from Juno's first flybys are expected to be published within the next few months.

JUNO orbiting Jupiter. Image Credit: NASA

Juno launched on Aug. 5, 2011, from Cape Canaveral, Florida, and arrived in orbit around Jupiter on July 4, 2016. During its mission of exploration, Juno soars low over the planet's cloud tops -- as close as about 2,600 miles (4,100 kilometers). During these flybys, Juno is probing beneath the obscuring cloud cover of Jupiter and studying its auroras to learn more about the planet's origins, structure, atmosphere and magnetosphere.

NASA's Jet Propulsion Laboratory, Pasadena, California, manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio. The Juno mission is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama, for the Science Mission Directorate. Lockheed Martin Space Systems, Denver, built the spacecraft. JPL is a division of Caltech in Pasadena, California.

More information on the Juno mission is available at:

The public can follow the mission on Facebook and Twitter at:

Images (mentioned), Text, Credits: NASA/Dwayne Brown/Laurie Cantillo/Martin Perez/JPL/DC Agle.


Hubble Spots Two Interacting Galaxies Defying Cosmic Convention

NASA - Hubble Space Telescope patch.

March 24, 2017

Some galaxies are harder to classify than others. Here, Hubble’s trusty Wide Field Camera 3 (WFC3) has captured a striking view of two interacting galaxies located some 60 million light-years away in the constellation of Leo (The Lion). The more diffuse and patchy blue glow covering the right side of the frame is known as NGC 3447 — sometimes NGC 3447B for clarity, as the name NGC 3447 can apply to the overall duo. The smaller clump to the upper left is known as NGC 3447A.

Overall, we know NGC 3447 comprises a couple of interacting galaxies, but we’re unsure what each looked like before they began to tear one another apart. The two sit so close that they are strongly influenced and distorted by the gravitational forces between them, causing the galaxies to twist themselves into the unusual and unique shapes seen here. NGC 3447A appears to display the remnants of a central bar structure and some disrupted spiral arms, both properties characteristic of certain spiral galaxies. Some identify NGC 3447B as a former spiral galaxy, while others categorize it as being an irregular galaxy.

Hubble Space Telescope

For Hubble’s image of the Whirlpool Galaxy, visit:

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

Best regards,

NASA Sees Tropical Cyclone Caleb's Heaviest Rainfall

NASA & JAXA -  Global Precipitation Measurement (GPM)logo.

 March 24, 2017

Caleb (South Indian Ocean)

Tropical cyclone Caleb formed on March 23 in the South Indian Ocean southwest of the Indonesian Island of Sumatra. The GPM core observatory satellite had a fairly good view of the newly formed tropical cyclone when it flew overhead and analyzed its rainfall and found the heaviest precipitation was affected by westerly winds.

Image above: On March 23, 2017 at 0756 UTC (3:56 a.m. EST) NASA/JAXA's GPM rainfall measurements showed that convective storms on tropical cyclone Caleb's western side were dropping rain at a rate of almost 84 mm (3.3 inches) per hour. Image Credits: NASA/JAXA, Hal Pierce.

The Global Precipitation Measurement mission or GPM core satellite passed over the Southern Indian Ocean on March 23, 2017 at 0756 UTC (3:56 a.m. EST). The satellite's Microwave Imager (GMI) revealed the locations of rainfall within the tropical cyclone. Rainfall measurements derived from the GMI showed that convective storms were dropping rain at a rate of almost 84 mm (3.3 inches) per hour on Caleb's western side.

GPM is a joint mission between NASA and the Japan Aerospace Exploration Agency (JAXA).

On March 24 at 0900 UTC (5 a.m. EST), Caleb had maximum sustained winds near 35 knots (40 mph/62 kph). It was centered near 14.6 degrees south latitude and 101.0 degrees east longitude, about 270 nautical miles (310.7 miles/500.4 km) east-southeast of Cocos Island. Caleb was moving to the south-southeastward at 4 knots (4.6 mph/7.4 kph).

NASA-JAXA's GPM Satellite Sees Caleb's Heaviest Rains West of Center

Video above: On March 23, 2017 at 0756 UTC (3:56 a.m. EST) NASA/JAXA's GPM rainfall measurements showed that convective storms on tropical cyclone Caleb's western side were dropping rain at a rate of almost 84 mm (3.3 inches) per hour. Video Credits: NASA/JAXA, Hal Pierce.

Satellite imagery on March 24 revealed that Caleb was struggling, and the Joint Typhoon Warning Center (JTWC) said that "environmental conditions are not showing any signs of improvement as the easterly flow aloft is still a dominant feature increasing the vertical wind shear."

The JTWC said that over the next 12 to 24 hours Caleb will slow as it encounters a building subtropical ridge (elongated area of high pressure) to the south. The system will assume a quasi-stationary track beyond 24 hours and weaken significantly due to increasing wind shear and cooler sea surface temperatures. Caleb is expected to dissipate in three days over the open waters of the Indian Ocean.

Related links:

GPM (Global Precipitation Measurement): and

Image (mentioned), Video (mentioned), Text, Credits: NASA's Goddard Space Flight Center/Rob Gutro/Hal Pierce.