ISOLDE steps into unexplored region of the nuclear chart

CERN - European Organization for Nuclear Research logo.

28 January, 2020

Knowledge of this almost uncharted region could help cast light on how gold and other heavy elements form in the universe 

Image above: Instrumentation inside the ISOLDE Solenoidal Spectrometer (Image: Ben Kay, Argonne National Laboratory).

Many heavy elements, such as gold, are thought to form in cosmic environments rich in neutrons – think supernovae or mergers of neutron stars. In these extreme settings, atomic nuclei can rapidly capture neutrons and become heavier, creating new elements. At the far reaches of the nuclear chart, which arranges all known nuclei according to their number of protons and neutrons, lie unexplored nuclei that are crucial to understanding the details of this rapid neutron-capture process. This is especially the case for nuclei with fewer than 82 protons and more than 126 neutrons.

Researchers using CERN’s nuclear-physics facility ISOLDE have now stepped into this nearly uncharted region of the nuclear chart with a first study of the neutron structure of the mercury isotope ²⁰⁷Hg. This isotope is not directly involved in the rapid neutron-capture process, or “r-process”, but it is a relatively close neighbour of r-process nuclei lying in this almost unexplored region. As such, ²⁰⁷Hg could help reveal some of the nuclear secrets of r-process nuclei and hence shed light on the origin of heavy elements.

To study the neutron structure of  ²⁰⁷Hg, the researchers first took ²⁰⁶Hg isotopes that were produced along with hundreds of other exotic isotopes at ISOLDE by firing a 1.4 billion electronvolt proton beam from the Proton Synchrotron Booster onto a molten lead target. The ²⁰⁶Hg isotopes, which have one fewer neutron in the nucleus than ²⁰⁷Hg, were then accelerated in the facility’s HIE-ISOLDE accelerator to an energy of about 1.52 billion electronvolts – the highest energy ever achieved at HIE-ISOLDE. The researchers then focused the ²⁰⁶Hg isotopes at a deuterium target inside the ISOLDE Solenoidal Spectrometer (ISS), a newly developed magnetic spectrometer that was able to reveal events in which the ²⁰⁶Hg isotopes captured a neutron and turned into excited ²⁰⁷Hg isotopes.

From the analysis of these events, the researchers determined the binding energies of the nuclear orbitals into which the neutron is captured, that is, the degree to which the captured neutron is bound to the other neutrons and protons. They then fed these results into theoretical models of the r-process to test and challenge these models.

“This result marks the first exploration of the neutron structure of the ²⁰⁷Hg nucleus, paving the way for future experimental studies, with the ISS instrument at ISOLDE and at next-generation nuclear-physics facilities, of the almost uncharted nuclear region where ²⁰⁷Hg lies,” says principal investigator Ben Kay from Argonne National Laboratory, where the technique that underlies the ISS was pioneered.

“This study was possible thanks to three things: the completed HIE-ISOLDE accelerator system, which now allows radioactive isotopes to be accelerated to energies close to 10 million electronvolts per proton or neutron; the installation of the ISS, a former MRI magnet repurposed for studies of exotic nuclei by a collaboration from the UK, Belgium and CERN; and, last but not least, a particle-detector system that was supplied by the Argonne National Laboratory and allowed the experiment to be performed just before the beginning of the ongoing shutdown of CERN’s accelerator complex,” explained ISOLDE spokesperson Gerda Neyens.

Note:

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

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

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 23 Member States.

Related links:

ISOLDE: https://home.cern/science/experiments/isolde

Study: https://arxiv.org/abs/2001.00976

Proton Synchrotron Booster: https://home.cern/science/accelerators/proton-synchrotron-booster

For more information about European Organization for Nuclear Research (CERN), Visit: https://home.cern/

Image (mentioned), Text, Credits: CERN/Ana Lopes.

Best regards, Orbiter.ch

Ultra-Cold Science, CubeSats and Spaceship Departures Coming Up

ISS - Expedition 61 Mission patch.

January 28, 2020

Ultra-cold science and nanosatellites kept the Expedition 61 crew busy on Tuesday while the International Space Station is getting ready for the departure of a cargo craft and crew ship.

The Cold Atom Lab (CAL) enables research into the quantum effects of gases chilled to nearly absolute zero, which is colder than the average temperature of the universe. NASA Flight Engineers Jessica Meir and Christina Koch opened up the CAL today to swap and clean hardware inside the quantum research device.

Image above: Astronauts Andrew Morgan (left) and Luca Parmitano are pictured shortly after they began their mission aboard the International Space Station in July of 2019. Image Credit: NASA.

Meir first joined NASA astronaut Andrew Morgan in the Kibo laboratory module to help him set up the Cyclops small satellite deployer. Morgan installed Cyclops, loaded with a Department of Defense experimental satellite, inside Kibo’s airlock for depressurization.

Mission controllers will then remotely command the Japanese robotic arm to grapple and deploy Cyclops outside Kibo overnight. The tiny satellite, packed with a variety of space weather and star tracker experiments, will be deployed into Earth orbit Wednesday morning.

Meir then installed a different small satellite deployer, this one called SlingShot, on the Cygnus space freighter attached to the Unity module. The SlingShot, attached to Cygnus’ hatch, will release a variety of small satellites after the U.S. cargo craft departs the space station on Friday at 9:35 a.m. EST. The suite of eight CubeSats will study different optical and communication technologies as well as atmospheric and natural phenomena.

International Space Station (ISS). Animation Credit: NASA

Koch is getting ready to come home on Feb. 6 with fellow crewmates Luca Parmitano of ESA (European Space Agency) and Alexander Skvortsov of Roscosmos. The trio performed leak checks today on the Sokol launch and entry suits they will wear aboard the Soyuz MS-13 crew ship when they parachute to a landing in Kazakhstan.

Upon landing, Koch will have lived in space continuously for 328 days on her first mission. She will be second only to former astronaut Scott Kelly who lived in space 340 days for the single longest spaceflight by a U.S. astronaut.

Related links:

Expedition 61: https://www.nasa.gov/mission_pages/station/expeditions/expedition61/index.html

Cold Atom Lab (CAL): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=7396

Kibo laboratory module: https://www.nasa.gov/mission_pages/station/structure/elements/japan-kibo-laboratory

Cyclops: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=986

Experimental satellite: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7347

SlingShot: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=7847

Unity module: https://www.nasa.gov/mission_pages/station/structure/elements/unity

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

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

Best regards, Orbiter.ch

Chandra Spots a Mega-Cluster of Galaxies in the Making

NASA - Chandra X-ray Observatory patch.

Jan. 28, 2020

Astronomers using data from NASA's Chandra X-ray Observatory and other telescopes have put together a detailed map of a rare collision between four galaxy clusters. Eventually all four clusters — each with a mass of at least several hundred trillion times that of the Sun — will merge to form one of the most massive objects in the universe.

Galaxy clusters are the largest structures in the cosmos that are held together by gravity. Clusters consist of hundreds or even thousands of galaxies embedded in hot gas, and contain an even larger amount of invisible dark matter. Sometimes two galaxy clusters collide, as in the case of the Bullet Cluster, and occasionally more than two will collide at the same time.

The new observations show a mega-structure being assembled in a system called Abell 1758, located about 3 billion light-years from Earth. It contains two pairs of colliding galaxy clusters that are heading toward one another. Scientists first recognized Abell 1758 as a quadruple galaxy cluster system in 2004 using data from Chandra and XMM-Newton, a satellite operated by the European Space Agency (ESA).

Each pair in the system contains two galaxy clusters that are well on their way to merging. In the northern (top) pair seen in the composite image, the centers of each cluster have already passed by each other once, about 300 to 400 million years ago, and will eventually swing back around. The southern pair at the bottom of the image has two clusters that are close to approaching each other for the first time.

Chandra X-ray Observatory

Chandra X-ray Observatory: https://www.nasa.gov/mission_pages/chandra/main/index.html

Image, Animation Credit: X-ray: NASA/CXC/SAO/G.Schellenberger et al.; Optical:SDSS/Text: NASA/Yvette Smith.

Greetings, Orbiter.ch

NASA Selects First Commercial Destination Module for International Space Station

NASA logo / Axiom Space logo.

Jan. 27, 2020

NASA has selected Axiom Space of Houston to provide at least one habitable commercial module to be attached to the International Space Station as the agency continues to open the station for commercial use.

International Space Station (ISS). Image Credit: NASA

“NASA has once again recognized the hard work, talent, and experience of Houstonians as we expand the International Space Station and promote commercial opportunities in space,” said Sen. John Cornyn of Texas. “I’m proud Axiom will continue to build upon Texas’ legacy of leading the nation in human space exploration.”

This selection is a significant step toward enabling the development of independent commercial destinations that meet NASA’s long-terms needs in low-Earth orbit, beyond the life of the space station, and continue to foster the growth of a robust low-Earth orbit economy.

"Today’s announcement is an exciting and welcome step forward in the efforts to commercialize low-Earth orbit,” said Sen. Ted Cruz of Texas. “This partnership between NASA and Axiom Space – a Houston, Texas original – illustrates how critically important the International Space Station is, and will continue to be, for developing new technologies for low-Earth orbit and beyond, and for continuing America’s leadership in space. Congratulations to Axiom Space on this exciting award – Houston is known as Space City for a reason, and I look forward to this great Space City company and NASA turning this announcement into reality."

Image - Axiom Segment On ISS

The element will attach to the space station’s Node 2 forward port to demonstrate its ability to provide products and services and begin the transition to a sustainable low-Earth orbit economy in which NASA is one of many customers. NASA and Axiom next will begin negotiations on the terms and price of a firm-fixed-price contract with a five-year base performance period and a two-year option.

“Congratulations to Axiom Space! This is not only a win for Texas, Johnson Space Center, and the International Space Station, it is also a great step forward for NASA as we move towards an increased commercial presence in low-Earth orbit,” said Rep. Brian Babin of Texas. “I am proud to see this work coming to Space City – Houston, Texas – as the Lone Star State continues to lead in space exploration well into the future.”

Developing commercial destinations in low-Earth orbit is one of five elements of NASA’s plan to open the International Space Station to new commercial and marketing opportunities. The other elements of the five-point plan include efforts to make station and crew resources available for commercial use through a new commercial use and pricing policy; enable private astronaut missions to the station; seek out and pursue opportunities to stimulate long-term, sustainable demand for these services; and quantify NASA’s long-term demand for activities in low-Earth orbit.

Image - Axiom Modules Connected To ISS

“Axiom’s work to develop a commercial destination in space is a critical step for NASA to meet its long-term needs for astronaut training, scientific research, and technology demonstrations in low-Earth orbit,” said NASA Administrator Jim Bridenstine. “We are transforming the way NASA works with industry to benefit the global economy and advance space exploration. It is a similar partnership that this year will return the capability of American astronauts to launch to the space station on American rockets from American soil.”

NASA selected Axiom from proposals submitted in response to a solicitation through Appendix I of NASA’s Next Space Technologies for Exploration Partnerships (NextSTEP) 2 Broad Agency Announcement, which offered private industry use of the station utilities and a port to attach one or more commercial elements to the orbiting laboratory.

Because commercial destinations are considered a key element of a robust economy in low-Earth orbit, NASA also plans to issue a final opportunity to partner with the agency in the development of a free-flying, independent commercial destination. Through these combined efforts to develop commercial destinations, NASA is set to meet its long-term needs in low-Earth orbit well beyond the life of the station.

Image - Axiom Earth Observatory Exterior

The agency will continue to need low-Earth orbit microgravity research and testing to enable future missions to the Moon and Mars, including the arrival of the first woman and next man on the Moon with the Artemis III mission as part of the agency’s Artemis lunar exploration plans.

Axiom Space

Video above: (Animation) Missions to the International Space Station today. The world’s first commercial space station tomorrow. Video Credit: Axiom Space.

Related links:

Axiom Space: https://www.axiomspace.com/

Appendix I of NASA’s Next Space Technologies for Exploration Partnerships (NextSTEP): https://www.nasa.gov/nextstep/issport

Learn more about NASA’s efforts to develop a robust low-Earth orbit economy at: https://www.nasa.gov/leo-economy

Commercial Space: http://www.nasa.gov/exploration/commercial/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Images, Video, Text, Credits: NASA/Karen Northon/Stephanie Schierholz/Matthew Rydin/JSC/Gary Jordan/Axiom Space.

Greetings, Orbiter.ch

Science Soon Resumes on Cosmic Ray Detector, Crew Packs Cargo Ship for Departure

ISS - Expedition 61 Mission patch.

January 27, 2020

Engineers on the ground have begun powering up the Alpha Magnetic Spectrometer’s (AMS) thermal system following a successful repair spacewalk over the weekend. The Expedition 61 astronauts are now preparing a U.S. cargo craft for its departure at the end of the week.

It took four spacewalks over three months to restore and upgrade thermal operations on the AMS. Astronauts Andrew Morgan and Luca Parmitano wrapped up the complex repair job on Saturday for the 8-year-old cosmic particle detector. Soon after the spacewalk, payload controllers reported stable cooling operations on the AMS, and are continuing to monitor its thermal conditions. The AMS will soon resume its search for evidence of dark matter and antimatter once the system checkouts are complete.

Image above: Spacewalkers Andrew Morgan and Luca Parmitano work on get-ahead tasks after completing thermal repairs on the Alpha Magnetic Spectrometer. Image Credit: NASA TV.

The crew are now turning their attention to packing Northrop Grumman’s Cygnus resupply ship with trash and discarded hardware. Robotics controllers in Mission Control will command the Canadarm2 robotic arm to release Cygnus on Friday at 9:35 a.m. EST after 88 days attached to the Unity module. The private cargo carrier will reenter Earth’s atmosphere over the South Pacific for a fiery, but safe disposal.

NASA Flight Engineers Jessica Meir and Christina Koch started Monday on housecleaning tasks. They were joined by Morgan and Parmitano cleaning fans and filters and disinfecting surfaces containing microbes and condensation.

Image above: The U.S. Cygnus space freighter is pictured as the Canadarm2 robotic arm, guided by NASA astronaut Jessica Meir with fellow Flight Engineer Christina Koch as her back up, reaches out to grapple the 12th resupply ship from Northrop Grumman on November 4, 2019. Image Credit: NASA.

Cosmonaut Alexander Skvortsov is getting the Soyuz MS-13 crew ship ready for its return to Earth on Feb. 6. He will parachute to a landing in Kazakhstan with Koch and Parmitano just three and half hours after undocking from the Poisk module. Koch will have lived in space continuously for 328 days on her first mission, second only to former astronaut Scott Kelly who lived in space 340 days for the single longest spaceflight by a U.S. astronaut.

Related article:

NASA TV to Air Departure of Cygnus Cargo Spacecraft from Space Station
https://www.nasa.gov/press-release/nasa-tv-to-air-departure-of-cygnus-cargo-spacecraft-from-space-station

Related links:

Expedition 61: https://www.nasa.gov/mission_pages/station/expeditions/expedition61/index.html

Alpha Magnetic Spectrometer (AMS): https://cms.nasa.gov/mission_pages/station/research/alpha-magnetic-spectrometer.html

Spacewalks: https://www.nasa.gov/mission_pages/station/spacewalks

Cygnus resupply ship: https://www.nasa.gov/feature/northrop-grumman-cygnus-launches-arrivals-and-departures/

Canadarm2: https://www.nasa.gov/mission_pages/station/structure/elements/mobile-servicing-system.html

Unity module: https://www.nasa.gov/mission_pages/station/structure/elements/unity

Soyuz MS-13 crew ship: https://www.nasa.gov/feature/soyuz-launches-arrivals-and-departures/

Poisk module: https://www.nasa.gov/mission_pages/station/structure/elements/poisk-mini-research-module-2

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

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

Best regards, Orbiter.ch

Tarantula Nebula Spins Web of Mystery in Spitzer Image

NASA - Spitzer Space Telescope patch.

Jan. 27, 2020

Image above: This image from NASA's Spitzer Space Telescope shows the Tarantula Nebula in two wavelengths of infrared light. The red regions indicate the presence of particularly hot gas, while the blue regions are interstellar dust that is similar in composition to ash from coal or wood-burning fires on Earth. Image Credits: NASA/JPL-Caltech.

The Tarantula Nebula, seen in this image by the Spitzer Space Telescope, was one of the first targets studied by the infrared observatory after its launch in 2003, and the telescope has revisited it many times since. Now that Spitzer is set to be retired on Jan. 30, 2020, scientists have generated a new view of the nebula from Spitzer data.

This high-resolution image combines data from multiple Spitzer observations, most recently in February and September 2019.

"I think we chose the Tarantula Nebula as one of our first targets because we knew it would demonstrate the breadth of Spitzer's capabilities," said Michael Werner, who has been Spitzer's project scientist since the mission's inception and is based at NASA's Jet Propulsion Laboratory in Pasadena, California. "That region has a lot of interesting dust structures and a lot of star formation happening, and those are both areas where infrared observatories can see a lot of things that you can't see in other wavelengths."

Infrared light is invisible to the human eye, but some wavelengths of infrared can pass through clouds of gas and dust where visible light cannot. So scientists use infrared observations to view newborn stars and still-forming "protostars," swaddled in the clouds of gas and dust from which they formed.

Spitzer Space Telescope

Located in the Large Magellanic Cloud — a dwarf galaxy gravitationally bound to our Milky Way galaxy — the Tarantula Nebula is a hotbed of star formation. In the case of the Large Magellanic Cloud, such studies have helped scientists learn about rates of star formation in galaxies other than the Milky Way.

The nebula also hosts R136, a "starburst" region, where massive stars form in extremely close proximity and at a rate far higher than in the rest of the galaxy. Within R136, in an area less than 1 light-year across (about 6 trillion miles, or 9 trillion kilometers), there are more than 40 massive stars, each containing at least 50 times the mass of our Sun. By contrast, there are no stars at all within 1 light-year of our Sun. Similar starburst regions have been found in other galaxies, containing dozens of massive stars — a higher number of massive stars than what is typically found in the rest of their host galaxies. How these starburst regions arise remains a mystery.

On the outskirts of the Tarantula Nebula, you can also find one of astronomy's most-studied stars that has exploded in a supernova. Dubbed 1987A because it was the first supernova spotted in 1987, the exploded star burned with the power of 100 million Suns for months. The shockwave from that event continues to move outward into space, encountering material ejected from the star during its dramatic death.

When the shockwave collides with dust, the dust heats up and begins to radiate in infrared light. In 2006, Spitzer observations saw that light and determined that the dust is largely composed of silicates, a key ingredient in the formation of rocky planets in our solar system. In 2019, scientists used Spitzer to study 1987A to monitor the changing brightness of the expanding shockwave and debris to learn more about how these explosions change their surrounding environment.  

Image above: This annotated image from NASA's Spitzer Space Telescope shows the Tarantula Nebula in infrared light. The supernova 1987A and the starburst region R136 are noted. The magenta-colored regions are primarily interstellar dust that is similar in composition to ash from coal or wood fires on Earth. Image Credits: NASA/JPL-Caltech.

More From Spitzer

To see more amazing images from Spitzer, check out the NASA Selfies App, which has a bundle of new Spitzer images. Available for iOS and Android, the app lets you create a snapshot of yourself in a virtual spacesuit, posing in front of gorgeous cosmic locations, including the Tarantula Nebula. Its simple interface lets you snap a photo of yourself, pick your background and share on social media while also providing you some of the science behind the images.

NASA Selfies App: https://www.jpl.nasa.gov/apps/#nasaselfies

For an even more immersive Spitzer experience, check out the new Spitzer Final Voyage VR experience, which places you in a 360-degree starscape that replicates Spitzer's current location orbiting the Sun, about 160 million miles (260 million kilometers) behind Earth. The narrated video shows you how the infrared telescope operates and what the universe looks like in infrared light. The VR experience is viewable on the Spitzer YouTube channel using mobile-based VR headsets, and in the Exoplanets Excursion VR app via Oculus Rift and HTC Vive headsets.

Related articles:

NASA Celebrates the Legacy of the Spitzer Space Telescope
https://orbiterchspacenews.blogspot.com/2020/01/nasa-celebrates-legacy-of-spitzer-space.html

NASA Says Goodbye to One of Agency's Great Observatories
https://orbiterchspacenews.blogspot.com/2020/01/nasa-says-goodbye-to-one-of-agencys.html

Sixteen Images for Spitzer's Sweet 16
https://orbiterchspacenews.blogspot.com/2019/08/sixteen-images-for-spitzers-sweet-16.html

How NASA's Spitzer Has Stayed Alive for So Long
https://orbiterchspacenews.blogspot.com/2019/06/how-nasas-spitzer-has-stayed-alive-for.html

Related links:

Spitzer YouTube channel: https://www.youtube.com/watch?v=kyXqRD_z8c0

More information about Spitzer is available at the following site:

https://www.nasa.gov/mission_pages/spitzer/main

Images (mentioned), Animation, Text, Credits: NASA/Tony Greicius/JPL/Calla Cofield.

Greetings, Orbiter.ch

CryoSat sheds new light on Antarctica’s biggest glacier

ESA - CryoSat Mission logo.

Jan. 27, 2020

Ice loss from Pine Island Glacier has contributed more to sea-level rise over the past four decades than any other glacier in Antarctica. However, the way this huge glacier is thinning is complex, leading to uncertainty about how it is likely to raise sea level in the future. Thanks to ESA’s CryoSat mission, scientists have now been able to shed new light on these complex patterns of ice loss.

CryoSat

Although Pine Island Glacier is one of the most intensively and extensively investigated glacier system in Antarctica, different model projections of future mass loss give conflicting results; some suggesting mass loss could dramatically increase over the next few decades, resulting in a rapidly growing contribution to sea level, while others indicate a more moderate response.

Identifying which is the more likely behaviour is important for understanding future sea-level rise and how this vulnerable part of Antarctica is going to evolve over the coming decades.

In a paper published in Nature Geoscience, scientists from the University of Bristol, UK, describe how they used information from CryoSat to help clarify the situation. They discovered that the pattern of ice loss is evolving in complex ways, both in space and time.

Rates in the fast-flowing central trunk of the glacier have decreased by about a factor of five since 2007 – and this is the opposite of what was observed prior to 2010.

These new results suggest that rapid migration of the grounding line, the place where the grounded ice first meets the ocean, is unlikely over the next decades, without a major change in the role of the ocean in ice loss. Instead, the results support model simulations that imply that the glacier will continue to lose mass, but not at much greater rates than present.

Pine Island Glacier thinning

Lead author Prof. Jonathan Bamber from the University of Bristol’s School of Geographical Sciences, said, “This could seem like a ‘good news story’, but it’s important to remember that we still expect this glacier to continue to lose mass in the future and for that trend to increase over time, just not quite as fast as some model simulations suggested.

“It’s really important to understand why the models are producing different behaviour in the future and to get a better handle on how the glacier will evolve with the benefit of these new observations.

“In our study, we didn’t make projections, but with the aid of these new data we can improve model projections for this part of Antarctica.”

Tommaso Parrinello, ESA’s CryoSat mission manger, added, “In April, CryoSat will have been in orbit for 10 years, far exceeding its expected life. We continue to be proud of the contribution to science this extraordinary satellite mission is making.

“And here, with the issue of sea-level rise a major global concern, the better equipped we are with facts the better it is. CryoSat has helped clarify the situation at Pine Island Glacier, which is not only important for our scientific understanding, but ultimately for society at large.”

Related links:

Nature Geoscience: https://www.nature.com/articles/s41561-019-0527-z

CryoSat: http://www.esa.int/Applications/Observing_the_Earth/CryoSat

Image, Animation, Text, Credits: ESA/AOES Medialab/University of Bristol.

Greetings, Orbiter.ch