vendredi 9 février 2018

A Swiss upsets the foundations of the universe

University Of Basel logo.

Feb. 9, 2018

A doctoral student from the Uni Basel is currently in the forefront of the renowned magazine "Science" with a revolutionary theory. In particular, he questions the existence of dark matter.

Oliver Müller. Image Credit: Oliver Müller

The young man and his team found that the satellite galaxies were moving according to a common pattern of movements.

What if the Milky Way did not work the way scientists think? And if dark matter did not exist? It is with these questions that the 28-year-old Oliver Müller of Basel tickles astronomy specialists around the world, writes "20 Minuten". He and his team base their interrogations on a theory that they developed and which is currently found in "Science", the most famous scientific magazine of the world.

Image above: Oliver Müller and his theory on the movement of dwarf galaxies make the front page of the magazine "Science". Image Credit: Science.

Until now, astronomy was based on the assumption that small galaxies surrounding large star systems were randomly distributed and moving in a chaotic manner. Another theory commonly accepted in the field of astronomy: these small galaxies are interconnected by dark matter, invisible. However, Oliver Müller's discoveries put this into question.

A "universal phenomenon"

After studying the constellations of the Centaurus galaxy A, the young man and his team found that satellite galaxies moved in a common pattern of motion and gravitated around the mother galaxy. "This coherent movement seems to be a universal phenomenon, which requires new explanations," says the Bâlois. His discovery upsets not only all that has been commonly accepted about it so far, but also questions the existence of dark matter.

Image above: The young man and his team found that satellite galaxies were moving in a pattern of common movements. Credits: Christian Wolf & SkyMapper Team / Australian National University.

Oliver Müller is currently doing doctorate at the Uni Basel. The young man will be the last to receive a doctorate in astronomy at the Rhine High School, explains the "Tageswoche". The institute has in fact already been closed several years ago for reasons of economy. Reason why the course of the young man was integrated in that of the physicists. The last professor in astronomy will also retire in September.

University of Basel, Department of Physics:

Images (mentioned), Text, Credits: DAF/OFU/ Aerospace/Roland Berga.

Best regards,

NASA’s Continued Focus on Returning U.S. Human Spaceflight Launches

NASA logo.

February 9, 2018

NASA’s Commercial Crew Program and private industry partners, Boeing and SpaceX, continue to develop the systems that will return human spaceflight to the United States. Both commercial partners are undertaking considerable amounts of testing in 2018 to prove space system designs and the ability to meet NASA’s mission and safety requirement for regular crew flights to the International Space Station.

International Space Station (ISS). Image Credit: NASA

“The work Boeing and SpaceX are doing is incredible. They are manufacturing spaceflight hardware, performing really complicated testing and proving their systems to make sure we get it right.” said Kathy Lueders, program manager NASA Commercial Crew Program. “Getting it right is the most important thing.”

Both Boeing and SpaceX plan to fly test missions without crew to the space station prior to test flights with a crew onboard this year. After each company’s test flights, NASA will work to certify the systems and begin post-certification crew rotation missions. The current flight schedules for commercial crew systems provide about six months of margin to begin regular, post-certification crew rotation missions to the International Space Station before contracted flights on Soyuz flights end in fall 2019.

As part of the agency’s normal contingency planning, NASA is exploring multiple scenarios as the agency protects for potential schedule adjustments to ensure continued U.S. access to the space station. One option under consideration would extend the duration of upcoming flight tests with crew targeted for the end of 2018 on the Boeing CST-100 Starliner and SpaceX Crew Dragon. The flights could be extended longer than the current two weeks planned for test flights, and likely less than a six-month full-duration mission. The agency also is assessing whether there is a need to add another NASA crew member on the flight tests.

This would not the first time NASA has expanded the scope of test flights. NASA had SpaceX carry cargo on its commercial demonstration flight to the International Space Station in 2012, which was not part of the original agreement. This decision allowed NASA to ensure the crew aboard the space station had the equipment, food and other supplies needed on the station after the end of the agency’s Space Shuttle Program.

As with all contingency plans, the options will receive a thorough review by the agency, including safety and engineering reviews. NASA will make a decision on these options within the next few months to begin training crews.

Related links:

Testing in 2018:

NASA’s Commercial Crew Program:

International Space Station (ISS):

Image (mentioned), Text, Credits: NASA/Stephanie Martin.

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New Horizons Captures Record-Breaking Images in the Kuiper Belt

NASA - New Horizons Mission logo.

Feb. 9, 2018

NASA’s New Horizons spacecraft recently turned its telescopic camera toward a field of stars, snapped an image – and made history.

Image above: With its Long Range Reconnaissance Imager (LORRI), New Horizons has observed several Kuiper Belt objects (KBOs) and dwarf planets at unique phase angles, as well as Centaurs at extremely high phase angles to search for forward-scattering rings or dust. These December 2017 false-color images of KBOs 2012 HZ84 (left) and 2012 HE85 are, for now, the farthest from Earth ever captured by a spacecraft. They're also the closest-ever images of Kuiper Belt objects. Image Credits: NASA/JHUAPL/SwRI.

The routine calibration frame of the “Wishing Well” galactic open star cluster, made by the Long Range Reconnaissance Imager (LORRI) on Dec. 5, was taken when New Horizons was 3.79 billion miles (6.12 billion kilometers, or 40.9 astronomical units) from Earth – making it, for a time, the farthest image ever made from Earth.

New Horizons was even farther from home than NASA’s Voyager 1 when it captured the famous “Pale Blue Dot” image of Earth. That picture was part of a composite of 60 images looking back at the solar system, on Feb. 14, 1990, when Voyager was 3.75 billion miles (6.06 billion kilometers, or about 40.5 astronomical units [AU]) from Earth. Voyager 1’s cameras were turned off shortly after that portrait, leaving its distance record unchallenged for more than 27 years.

LORRI broke its own record just two hours later with images of Kuiper Belt objects 2012 HZ84 and 2012 HE85 – further demonstrating how nothing stands still when you’re covering more than 700,000 miles (1.1 million kilometers) of space each day.

Image above: For a short time, this New Horizons Long Range Reconnaissance Imager (LORRI) frame of the "Wishing Well" star cluster, taken Dec. 5, 2017, was the farthest image ever made by a spacecraft, breaking a 27-year record set by Voyager 1. About two hours later, New Horizons later broke the record again. Image Credits: NASA/JHUAPL/SwRI.

“New Horizons has long been a mission of firsts — first to explore Pluto, first to explore the Kuiper Belt, fastest spacecraft ever launched,” said New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute in Boulder, Colorado. “And now, we’ve been able to make images farther from Earth than any spacecraft in history.”

Distance and Speed

New Horizons is just the fifth spacecraft to speed beyond the outer planets, so many of its activities set distance records. On Dec. 9 it carried out the most-distant course-correction maneuver ever, as the mission team guided the spacecraft toward a close encounter with a KBO named 2014 MU69 on Jan. 1, 2019. That New Year’s flight past MU69 will be the farthest planetary encounter in history, happening one billion miles beyond the Pluto system – which New Horizons famously explored in July 2015.

During its extended mission in the Kuiper Belt, which began in 2017, New Horizons is aiming to observe at least two-dozen other KBOs, dwarf planets and “Centaurs,” former KBOs in unstable orbits that cross the orbits of the giant planets. Mission scientists study the images to determine the objects’ shapes and surface properties, and to check for moons and rings. The spacecraft also is making nearly continuous measurements of the plasma, dust and neutral-gas environment along its path.

New Horizons spacecraft.Image Credit: NASA

The New Horizons spacecraft is healthy and is currently in hibernation. Mission controllers at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, will bring the spacecraft out of its electronic slumber on June 4 and begin a series of system checkouts and other activities to prepare New Horizons for the MU69 encounter.

Follow New Horizons on its trek through the Kuiper Belt at:

Images (mentioned), Text, Credits: NASA/Bill Keeter.


jeudi 8 février 2018

Russian Cargo Ship Preps for Launch While Crew Studies Life Science

ISS - Expedition 54 Mission patch.

Feb. 8, 2018

Image above: Russia’s Progress 69 resupply rocket is pictured in its processing facility at the Baikonur Cosmodrome in Kazakhstan. Image Credit: Roscosmos.

A Russian cargo craft is getting ready to roll out to its launch pad for a Sunday morning lift-off to resupply the International Space Station and the Expedition 54 crew. The astronauts and cosmonauts aboard the station are also preparing for the new space shipment and continuing a variety of life science studies.

Russia’s Progress 69 (69P) resupply ship is in its processing facility preparing to roll out to the launch pad Friday at the Baikonur Cosmodrome in Kazakhstan. The 69P is due to lift-off Sunday at 3:58 a.m. EST (2:58 p.m. Baikonur time) reaching the International Space Station in record time just three and half hours later.

Cosmonauts Alexander Misurkin and Anton Shkaplerov trained today for Sunday’s Progress’ automated rendezvous and docking set for 7:24 a.m. The duo practiced using the station’s telerobotically operated rendezvous unit in the unlikely event the Progress would need to be manually docked to the Zvezda service module.

Progress cargo spacecraft approaching ISS. Image Credit: NASA

Mice and plant studies are still under way this week to help researchers understand how organisms respond to living in space. Data collected from the space biology and botany studies may improve health treatments, benefit a wide variety of industry sectors and help NASA plan journeys farther into space.

Astronauts Scott Tingle and Norishige Kanai continued partnering together researching how a muscle maintenance drug affects muscle growth in mice living on the orbital lab. Results of the drug study may help combat muscle weakening in space and on Earth. Two-time station resident Joe Acaba processed and stowed samples for the Plant Gravity Processing experiment. The botany study is exploring how plants grow and how their roots orient themselves in outer space.

Related links:


Muscle growth in mice:

Plant Gravity Processing:

Expedition 54:

Space Station Research and Technology:

International Space Station (ISS):

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

Best regards,

Juno Completes Tenth Science Orbit of Jupiter

NASA - JUNO Mission logo.

Feb. 8, 2018

Image above: This image of Jupiter’s southern hemisphere was captured by NASA’s Juno spacecraft as it performed a close flyby of the gas giant planet on Dec. 16. Image Credits: NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstädt.

Juno accomplished a close flyby over Jupiter’s churning atmosphere on Wednesday, Feb. 7, successfully completing its tenth science orbit. The closest approach was at 6:36 a.m. PST (9:36 a.m. PST) Earth-received time. At the time of perijove (the point in Juno's orbit when it is closest to the planet's center), the spacecraft will be about 2,100 miles (3,500 kilometers) above the planet's cloud tops.

This flyby was a gravity science orientation pass. During orbits that highlight gravity experiments, Juno is in an Earth-pointed orientation that allows both the X-band and Ka-Band transmitter to downlink data in real-time to one of the antennas of NASA's Deep Space Network in Goldstone, California. All of Juno’s science instruments and the spacecraft’s JunoCam were in operation during the flyby, collecting data that is now being returned to Earth.

New raw images will be available for processing at:       

More information about Juno is at: and

Image (mentioned), Text, Credits: NASA/Tony Greicius.

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Splitting Slope Streaks

NASA - Mars Reconnaissance Orbiter (MRO) logo.

Feb. 8, 2018

This image from NASA's Mars Reconnaissance Orbiter (MRO) shows streaks forming on slopes when dust cascades downhill. The dark streak is an area of less dust compared to the brighter and reddish surroundings. What triggers these avalanches is not known, but might be related to sudden warming of the surface.

These streaks are often diverted by the terrain they flow down. This one has split into many smaller streaks where it encountered minor obstacles.

These streaks fade away over decades as more dust slowly settles out of the Martian sky.

The map is projected here at a scale of 25 centimeters (9.8 inches) per pixel. [The original image scale is 28.1 centimeters (11.1 inches) per pixel (with 1 x 1 binning); objects on the order of 84 centimeters (33.1 inches) across are resolved.] North is up.

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colorado. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.

Mars Reconnaissance Orbiter (MRO):

Image, Text, Credits: NASA/Tony Greicius/JPL-Caltech/Univ. of Arizona.


Tiny Crystal Shapes Get Close Look From Mars Rover

NASA - Mars Science Laboratory (MSL) logo.

Feb. 8, 2018

Image above: This self-portrait of NASA's Curiosity Mars rover shows the vehicle on Vera Rubin Ridge, which it's been investigating for the past several months. Poking up just behind Curiosity's mast is Mount Sharp, photobombing the robot's selfie. Image credits: NASA/JPL-Caltech/MSSS.

Star-shaped and swallowtail-shaped tiny, dark bumps in fine-layered bright bedrock of a Martian ridge are drawing close inspection by NASA's Curiosity Mars rover.

This set of shapes looks familiar to geologists who have studied gypsum crystals formed in drying lakes on Earth, but Curiosity's science team is considering multiple possibilities for the origin of these features on "Vera Rubin Ridge" on Mars.

One uncertainty the rover's inspection may resolve is the timing of when the crystal-shaped features formed, relative to when layers of sediment accumulated around them. Another is whether the original mineral that crystallized into these shapes remains in them or was subsequently dissolved away and replaced by something else. Answers may point to evidence of a drying lake or to groundwater that flowed through the sediment after it became cemented into rock.

Image above: This exposure of finely laminated bedrock on Mars includes tiny crystal-shaped bumps, plus mineral veins with both bright and dark material. This rock target, called "Jura," was imaged by the MAHLI camera on NASA's Curiosity Mars rover on Jan. 4, 2018, during Sol 1925 of the mission. Image Credits: NASA/JPL-Caltech/MSSS.

The rover team also is investigating other clues on the same area to learn more about the Red Planet's history. These include stick-shaped features the size of rice grains, mineral veins with both bright and dark zones, color variations in the bedrock, smoothly horizontal laminations that vary more than tenfold in thickness of individual layers, and more than fourfold variation in the iron content of local rock targets examined by the rover.

"There's just a treasure trove of interesting targets concentrated in this one area," said Curiosity Project Scientist Ashwin Vasavada of NASA's Jet Propulsion Laboratory, Pasadena, California. "Each is a clue, and the more clues, the better. It's going to be fun figuring out what it all means."

Vera Rubin Ridge stands out as an erosion-resistant band on the north slope of lower Mount Sharp inside Gale Crater. It was a planned destination for Curiosity even before the rover's 2012 landing on the crater floor near the mountain. The rover began climbing the ridge about five months ago and has now reached the uphill, southern edge. Some features here might be related to a transition to the next destination area uphill, which is called the "Clay Unit" because of clay minerals detected from orbit.

Image above: The surface of the Martian rock target in this stereo, close-up image from the Curiosity rover's MAHLI camera includes small hollows with a "swallowtail" shape characteristic of gypsum crystals. The view appears three-dimensional when seen through blue-red glasses with the red lens on the left. Image Credits: NASA/JPL-Caltech/MSSS.

The team drove the rover to a site called "Jura" in mid-January to examine an area where -- even in images from orbit -- the bedrock is noticeably pale and gray, compared to the red, hematite-bearing bedrock forming most of Vera Rubin Ridge.

"These tiny 'V' shapes really caught our attention, but they were not at all the reason we went to that rock," said Curiosity science-team member Abigail Fraeman of JPL. "We were looking at the color change from one area to another. We were lucky to see the crystals. They're so tiny, you don't see them until you're right on them."

The features are about the size of a sesame seed. Some are single elongated crystals. Commonly, two or more coalesce into V-shaped "swallowtails" or more complex "lark's foot" or star configurations. "These shapes are characteristic of gypsum crystals," said Sanjeev Gupta, a Curiosity science-team member at Imperial College, London, who has studied such crystals in rocks of Scotland. Gypsum is a form of calcium sulfate. "These can form when salts become concentrated in water, such as in an evaporating lake."

The finely laminated bedrock at Jura is thought to result from lakebed sedimentation, as has been true in several lower, older geological layers Curiosity has examined. However, an alternative to the crystals forming in an evaporating lake is that they formed much later from salty fluids moving through the rock. That is also a type of evidence Curiosity has documented in multiple geological layers, where subsurface fluids deposited features such as mineral veins.

Image above: The stick-shaped features on this Martian rock are about the size of grains of rice. This view from the MAHLI camera on NASA's Curiosity Mars rover covers an area about 2 inches across, on a target called "Haroldswick." The sticks might be bits of dark material from mineral veins in this area. Image Credits: NASA/JPL-Caltech/MSSS.

Some rock targets examined in the Jura area have two-toned mineral veins that formed after the lake sediments had hardened into rock. Brighter portions contain calcium sulfate; darker portions contain more iron. Some of the features shaped like gypsum crystals appear darker than gypsum, are enriched in iron, or are empty. These are clues that the original crystallizing material may have been replaced or removed by later effects of underground water.

The small, stick-shaped features were first seen two days before Curiosity reached Jura. All raw images from Mars rovers are quickly posted online, and some showing the "sticks" drew news-media attention comparing them to fossils. Among the alternative possibilities is that they are bits of the dark vein material. Rover science team members have been more excited about the swallowtails than the sticks.

"So far on this mission, most of the evidence we've seen about ancient lakes in Gale Crater has been for relatively fresh, non-salty water," Vasavada said. "If we start seeing lakes becoming saltier with time, that would help us understand how the environment changed in Gale Crater, and it's consistent with an overall pattern that water on Mars became more scarce over time."

Such a change could be like the difference between freshwater mountain lakes, resupplied often with snowmelt that keeps salts diluted, and salty lakes in deserts, where water evaporates faster than it is replaced.

If the crystals formed inside hardened rock much later, rather than in an evaporating lake, they offer evidence about the chemistry of a wet underground environment.

Image above: A mineral vein with bright and dark portions distiguishes this Martian rock target, called "Rona," near the upper edge of "Vera Rubin Ridge" on Mount Sharp. The MAHLI camera on NASA's Curiosity Mars rover took the image after the rover brushed dust off the gray area, roughly 2 inches by 3 inches. Image Credits: NASA/JPL-Caltech/MSSS.

"In either scenario, these crystals are a new type of evidence that builds the story of persistent water and a long-lived habitable environment on Mars," Vasavada said.

Variations in iron content in the veins, smaller features and surrounding bedrock might provide clues about conditions favorable for microbial life. Iron oxides vary in their solubility in water, with more-oxidized types generally less likely to be dissolved and transported. An environment with a range of oxidation states can provide a battery-like energy gradient exploitable by some types of microbes.

"In upper Vera Rubin Ridge, we see clues that there were fluids carrying iron and, through some mechanism, the iron precipitated out," Fraeman said. "There was a change in fluid chemistry that could be significant for habitability."

For more about NASA's Curiosity Mars rover mission, visit:

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


Leaky atmosphere linked to lightweight planet

ESA - Mars Express Mission patch.

8 February 2018

The Red Planet’s low gravity and lack of magnetic field makes its outermost atmosphere an easy target to be swept away by the solar wind, but new evidence from ESA’s Mars Express spacecraft shows that the Sun’s radiation may play a surprising role in its escape.

Terrestrial planet magnetospheres

Why the atmospheres of the rocky planets in the inner Solar System evolved so differently over 4.6 billion years is key to understanding what makes a planet habitable. While Earth is a life-rich water-world, our smaller neighbour Mars lost much of its atmosphere early in its history, transforming from a warm and wet environment to the cold and arid plains that we observe today. By contrast, Earth’s other neighbour Venus, which although inhospitable today is comparable in size to our own planet, and has a dense atmosphere.

One way that is often thought to help protect a planet’s atmosphere is through an internally generated magnetic field, such as at Earth. The magnetic field deflects charged particles of the solar wind as they stream away from the Sun, carving out a protective ‘bubble’ – the magnetosphere – around the planet.

At Mars and Venus, which don’t generate an internal magnetic field, the main obstacle to the solar wind is the upper atmosphere, or ionosphere. Just as on Earth, solar ultraviolet radiation separates electrons from the atoms and molecules in this region, creating a region of electrically charged – ionised – gas: the ionosphere. At Mars and Venus this ionised layer interacts directly with the solar wind and its magnetic field to create an induced magnetosphere, which acts to slow and divert the solar wind around the planet.

For 14 years, ESA’s Mars Express has been looking at charged ions, such as oxygen and carbon dioxide, flowing out to space in order to better understand the rate at which the atmosphere is escaping the planet.

The study has uncovered a surprising effect, with the Sun’s ultraviolet radiation playing a more important role than previously thought.

“We used to think that the ion escape occurs due to an effective transfer of the solar wind energy through the martian induced magnetic barrier to the ionosphere,” says Robin Ramstad of the Swedish Institute of Space Physics, and lead author of the Mars Express study.

“Perhaps counter-intuitively, what we actually see is that the increased ion production triggered by ultraviolet solar radiation shields the planet’s atmosphere from the energy carried by the solar wind, but very little energy is actually required for the ions to escape by themselves, due to the low gravity binding the atmosphere to Mars.”

Ion escape at Mars

The ionising nature of the Sun’s radiation is found to produce more ions than can be removed by the solar wind. Although the increased ion production helps to shield the lower atmosphere from the energy carried by the solar wind, the heating of the electrons appears to be sufficient to drag along ions under all conditions, creating a ‘polar wind’. Mars’ weak gravity – about one third that of Earth’s – means the planet cannot hold on to these ions and they readily escape into space, regardless of the extra energy supplied by a strong solar wind.

At Venus, where the gravity is similar to Earth’s, a lot more energy is required to strip the atmosphere in this way, and ions leaving the sunward side would likely fall back towards the planet on the lee-side unless they are accelerated further.

“We therefore conclude that in the present day, ion escape from Mars is primarily production-limited, and not energy-limited, whereas at Venus it is likely to be energy-limited given the larger planet’s higher gravity and high rate of ionisation, being nearer to the Sun,” adds Robin.

“In other words, the solar wind likely only had a very small direct effect on the amount of Mars atmosphere that has been lost over time, and rather only enhances the acceleration of already escaping particles.”

“Continuous monitoring of Mars since 2004, which covered the change in solar activity from solar minimum to maximum, gives us a large dataset that is vital in understanding the long-term behaviour of a planet’s atmosphere and its interaction with the Sun,” says Dmitri Titov, ESA’s Mars Express project scientist. “Collaboration with NASA’s MAVEN mission, which has been at Mars since 2014, is also allowing us to study the atmospheric escape processes in more detail.”

Mars Express

The study also has implications for the search for Earth-like atmospheres elsewhere in the Universe.

“Perhaps a magnetic field is not as important in shielding a planet’s atmosphere as the planet’s gravity itself, which defines how well it can hang on to its atmospheric particles after they have been ionised by the Sun’s radiation, regardless of the power of the solar wind,” adds Dmitri.

Notes for Editors:

“Global Mars-solar wind coupling and ion escape,” by Ramstad et al. is published in the Journal of Geophysical Research: Space Physics (2017) doi:10.1002/2017JA024306.

The study is based on data collected by the Mars Express ASPERA-3 instrument, the Analyser of Space Plasmas and Energetic Atoms.

A twin instrument also operated on ESA’s Venus Express, which concluded its mission in 2014.

Mars Express was launched on 2 June 2003 and reaches 15 years in space this year.

Related links:

Mars Express:


HRSC data viewer:

Mars Express overview:

Behind the lens...:

Frequently asked questions:

Images, Text, Credits: ESA/Markus Bauer/Dmitri Titov/Swedish Institute of Space Physics, Kiruna, Sweden/Robin Ramstad.

Best regards,

mercredi 7 février 2018

Bursting with Excitement – A Look at Bubbles and Fluids in Space

ISS - International Space Station logo.

Feb. 7, 2018

Image above: Roscosmos cosmonaut Oleg Kononenko conducts a sample exchange for the OASIS investigation. OASIS studies the unique behavior of liquid crystals in microgravity, including their overall motion and the merging of crystal layers known as smectic islands. Image Credit: NASA.

Watching a bubble float effortlessly through the International Space Station may be mesmerizing and beautiful to witness, but that same bubble is also teaching researchers about how fluids behave differently in microgravity than they do on Earth. The near-weightless conditions aboard the station allow researchers to observe and control a wide variety of fluids in ways that are not possible on Earth, primarily due to surface tension dynamics and the lack of buoyancy and sedimentation within fluids in the low-gravity environment. Understanding how fluids react in these conditions could lead to improved designs on fuel tanks, water systems and other fluid-based systems for space travel, as well as back on Earth.

Image above: NASA astronaut Kate Rubins sets up the Eli Lilly – Hard to Wet Surfaces Sample Module by injecting buffer solutions into the sample vials then mixing all six sample vials inside the Sample Module. This investigation studies how certain materials used in the pharmaceutical industry dissolve in water while in microgravity and could lead to improved tablet design. Image Credit: NASA.

Many investigations aboard the orbiting laboratory focus on fluid physics including the motion of liquids or the formation of bubbles. As on Earth, the formation of a bubble is sometimes a welcomed addition, but could also be an indication that something has gone wrong and must be reworked. Technology, investigations, and even tasks as simple as drinking water must take bubbles into consideration to be adapted to be functional in a microgravity environment.

Here are several investigations that use bubbles or fluid physics to their advantage:

- The Observation Analysis of Smectic Islands in Space (OASIS) investigation studied the unique behavior of liquid crystals in microgravity, noting the way these crystals act as both a solid and a liquid. Freely suspended crystal bubbles in microgravity represent nearly ideal fluid systems that are physically and chemically the same for the study of liquids in motion. Understanding how these crystals behave in space could lead to improvements to space-helmet micro-displays, as well as higher-quality screen displays on devices that use liquid crystal displays (LCDs).

- The Capillary Flow Experiment (CFE) sought to solve the problem of transferring fluid from one container to another in space. Without gravity, liquids don’t flow the same way they do on Earth, nor do they collect at the bottom of a container the way you would expect them to in gravity. Research found that although controlling the flow of fluids is difficult in space, capillary forces, or the ability for a fluid to flow through a narrow tube without the assistance of gravity, are still present. Capillary Flow Experiment 2 is expanding the fluid physics research conducted during CFE by exploring liquid’s ability to spread across a surface in microgravity. Results from the Capillary Flow Experiments could lead to more efficient fluid systems aboard future spacecraft, and a better understanding of capillary forces present within porous materials such as sand, soil, wicks and sponges.

- Researchers used the data collected during the Constrained Vapor Bubble investigation to gain a better understanding of the physics of evaporation and condensation and how they affect cooling processes. The results from this investigation aided in the development of simple models of bubble formation, which could help develop more efficient microelectronic cooling systems.

- The Eli Lilly Hard to Wet Surfaces investigation studies a material’s ability to dissolve in water while in microgravity, and may shed light on why drugs seem less effective in space compared to on Earth. Results from this investigation could help improve the design of tablets that dissolve in the body and lead to more efficient drug delivery on Earth and in space.

- The Nucleate Pool Boiling Experiment used microgravity to observe bubble growth from a heated surface and the subsequent detachment of the bubble to a cooler surrounding liquid, and the process by which bubbles can transfer heat through fluid flow. Information gathered during this investigation could lead to optimal equipment used to transfer heat in harsh environments such as the deep ocean, extreme cold and high altitudes.

- Two-Phase Flow investigates the heat transfer characteristics of how liquids flow when boiling in microgravity environments. Heat is removed in the boiling process normally by turning liquid into vapor at the heated surface, and that vapor returns to a liquid by way of condensation which continues to cycle and make a cooling system. Liquid and bubble behave much differently in space than on Earth, and this research may help to provide a fundamental understanding of the behaviors of bubble formation, liquid vapor flow in a tube and how heat transfers in cooling systems.

Image above: NASA astronaut Karen Nyberg watches a water bubble float freely between her and the camera, showing her image refracted in the droplet. Image Credit: NASA.

Designed to host a wide range of investigations, there are multiple facilities aboard the station for conducting fluid physics investigations. The Fluids Integrated Rack, the Fluid Science Laboratory, and the Fluid Physics Experiment Facility all host investigations in areas such as colloids, bubbles, wetting, capillary action and phase changes.

Related links:

Fluid physics:

Observation Analysis of Smectic Islands in Space (OASIS):

Capillary Flow Experiment (CFE):

Capillary Flow Experiment 2:

Constrained Vapor Bubble:

Eli Lilly Hard to Wet Surfaces:

Nucleate Pool Boiling Experiment:

Two-Phase Flow:

Fluids Integrated Rack:

Fluid Science Laboratory:

Fluid Physics Experiment Facility:

Space Station Research and Technology:

International Space Station (ISS):

Images (mentioned), Text, Credits: NASA/Michael Johnson/JSC/Jenny Howard.


Europe Nears 10 Years at Station; Crew Studies Mice and Plants

ISS - Expedition 54 Mission patch.

February 7, 2018

International Space Station (ISS). Animation credit: NASA

The International Space Station program is getting ready to recognize the 10th year in space of its Columbus lab module from the European Space Agency (ESA). The Expedition 54 crew members, meanwhile, spent the day helping scientists on the ground understand the impacts of living in space.

ESA is getting ready to celebrate the 10th anniversary of the launch of Columbus. The European lab module blasted off inside space shuttle Atlantis on Feb. 7, 2008, for a two-day ride to the station. Canadarm2, the station’s robotic arm, removed Columbus from Atlantis’s cargo bay two days after its arrival and attached it the starboard side of the Harmony module.

A month after the installation of Columbus, ESA launched its first resupply ship to the station. The “Jules Verne” Automated Transfer Vehicle (ATV-1) lifted off March 9, 2008, atop an Ariane-5 rocket from Kourou, French Guiana. The ATV-1 then took a month-long ride for a series navigation tests before to automatically docking to the station.

Image above: NASA astronaut Rex Walheim works outside Europe’s new Columbus lab module shortly after it was installed in February of 2008. Image Credit: NASA.

Astronauts Scott Tingle and Norishige Kanai continued studying mice on the space station for a drug study to potentially improve muscle health in microgravity and despite a lack of exercise. The rodents are housed in a special microgravity habitat for up to two months with results of the study helping scientists design therapies for humans with muscle-related ailments.

Flight Engineer Mark Vande Hei set up botany gear in the Columbus lab module for the Veggie-3 experiment. The long-running plant study is exploring the feasibility of harvesting edible plants such as cabbage, lettuce and mizuna for consumption during spaceflight. Samples are returned to Earth for analysis.

Related article:

Columbus: 10 years a lab

Related links:


“Jules Verne” Automated Transfer Vehicle (ATV-1):

Mice on the space station:


Expedition 54:

Space Station Research and Technology:

International Space Station (ISS):

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

Best regards,

Two Small Asteroids Safely Pass Earth This Week

Asteroid Watch logo.

Feb. 7, 2018

Animation above: Asteroid 2018 CB will pass closely by Earth on Friday, Feb. 9, at a distance of about 39,000 miles. Image Credits: NASA/JPL-Caltech.

Two small asteroids recently discovered by astronomers at the NASA-funded Catalina Sky Survey (CSS) near Tucson, Arizona, are safely passing by Earth within one lunar distance this week.

The first of this week’s close-approaching asteroids -- discovered by CSS on Feb. 4 -- is designated asteroid 2018 CC. Its close approach to Earth came Tuesday (Feb. 6) at 12:10 p.m. PST (3:10 p.m. EST) at a distance of about 114,000 miles (184,000 kilometers). The asteroid is estimated to be between 50 and 100 feet (15 and 30 meters) in size.

Of potentially greater interest is asteroid 2018 CB, which will also pass closely by Earth on Friday, Feb. 9, at around 2:30 p.m. PST (5:30 p.m. EST), at a distance of about 39,000 miles (64,000 kilometers), which is less than one-fifth the distance of Earth to the Moon). The asteroid, which is estimated to be between 50 and 130 feet (15 and 40 meters) in size, was also discovered by CSS on Feb. 4.

“Although 2018 CB is quite small, it might well be larger than the asteroid that entered the atmosphere over Chelyabinsk, Russia, almost exactly five years ago, in 2013,” said Paul Chodas, manager of the Center for Near-Earth Object Studies at NASA’s Jet Propulsion Laboratory in Pasadena, California. “Asteroids of this size do not often approach this close to our planet -- maybe only once or twice a year.”

Asteroids passing Earth. Image Credit: ESA

JPL hosts the Center for Near-Earth Object Studies for NASA's Near-Earth Object Observations Program, an element of the Planetary Defense Coordination Office within the agency's Science Mission Directorate.

More information about asteroids and near-Earth objects can be found at:

For more information about NASA's Planetary Defense Coordination Office, visit:

For asteroid and comet news and updates, follow AsteroidWatch on Twitter:

Animation (mentioned), Image (mentioned), Text, Credits: NASA/Tony Greicius/JPL/DC Agle.


mardi 6 février 2018

NASA Tests Atomic Clock for Deep Space Navigation

NASA Goddard Space Flight Center logo.

Feb. 6, 2018

In deep space, accurate timekeeping is vital to navigation, but not all spacecraft have precise timepieces aboard. For 20 years, NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, has been perfecting a clock. It’s not a wristwatch; not something available in a store. It’s the Deep Space Atomic Clock (DSAC), an instrument being built for deep space exploration.

Image above: A glimpse of the Deep Space Atomic Clock in the middle bay of the General Atomics Orbital Test Bed spacecraft. Image Credit: NASA.

Currently, most missions rely on ground-based antennas paired with atomic clocks for navigation. Ground antennas send narrowly focused signals to spacecraft, which, in turn, return the signal. NASA uses the difference in time between sending a signal and receiving a response to calculate the spacecraft’s location, velocity and path.

This method, though reliable, could be made much more efficient. For example, a ground station must wait for the spacecraft to return a signal, so a station can only track one spacecraft at a time. This requires spacecraft to wait for navigation commands from Earth rather than making those decisions onboard and in real-time.

Image above: The Atomic Clock, GPS Receiver, and Ultra-Stable Oscillator which make up the Deep Space Atomic Clock Payload, following integration into the middle bay of Surrey Satellite US's Orbital Test Bed Spacecraft. Image Credits: Surrey Satellite Technology.

“Navigating in deep space requires measuring vast distances using our knowledge of how radio signals propagate in space,” said Todd Ely of JPL, DSAC’s principal investigator. “Navigating routinely requires distance measurements accurate to a meter or better. Since radio signals travel at the speed of light, that means we need to measure their time-of-flight to a precision of a few nanoseconds. Atomic clocks have done this routinely on the ground for decades. Doing this in space is what DSAC is all about.”

The DSAC project aims to provide accurate onboard timekeeping for future NASA missions. Spacecraft using this new technology would no longer have to rely on two-way tracking. A spacecraft could use a signal sent from Earth to calculate position without returning the signal and waiting for commands from the ground, a process that can take hours. Timely location data and onboard control allows for more efficient operations, more precise maneuvering and adjustments to unexpected situations.

This paradigm shift enables spacecraft to focus on mission objectives rather than adjusting their position to point antennas earthward to close a link for two-way tracking.

Additionally, this innovation would allow ground stations to track multiple satellites at once near areas like Mars, crowded with NASA science missions. In certain scenarios, the accuracy of that tracking data would exceed traditional methods by a factor of five.

Image above: Tom Cwik, the head of JPL's Space Technology Program (left) and Allen Farrington, JPL Deep Space Atomic Clock Project Manager, view the integrated Atomic Clock Payload on Surrey Satellite US's Orbital Test Bed Spacecraft. Image Credits: Surrey Satellite Technology.

DSAC is an advanced prototype of a small, low-mass atomic clock based on mercury-ion trap technology. The atomic clocks at ground stations in the Deep Space Network are about the size of a refrigerator. DSAC is about the size of a four-slice toaster, and could be further miniaturized for future missions.

The DSAC test flight will take this technology from the laboratory to the space environment. While in orbit, the DSAC mission will use the navigation signals from U.S. GPS coupled with precise knowledge of GPS satellite orbits and clocks to confirm DSAC’s performance. The demonstration should confirm that DSAC can maintain time accuracy to better than two nanoseconds (.000000002 seconds) over a day, with a goal of achieving 0.3 nanosecond accuracy.

Once DSAC has proven the technology, future missions can use its technology enhancements. The clock promises increased tracking data quantity and improved tracking data quality. Coupling DSAC with onboard radio navigation could ensure that future exploration missions have the navigation data needed to send humans back to the moon and traverse the solar system.

Technologies aboard DSAC could also improve GPS clock stability and, in turn, the service GPS provides to users worldwide. Ground-based test results have shown DSAC to be upwards of 50 times more stable than the atomic clocks currently flown on GPS. DSAC promises to be the most stable navigation space clock ever flown.

“We have lofty goals for improving deep space navigation and science using DSAC,” said Ely. “It could have a real and immediate impact for everyone here on Earth if it’s used to ensure the availability and continued performance of the GPS system.”

DSAC is a partnership between NASA’s Space Technology Mission Directorate and the Space Communications and Navigation program office, a program under the Human Exploration and Operations Mission Directorate. DSAC will launch in 2018 as a hosted payload on General Atomic’s Orbital Test Bed spacecraft aboard the U.S. Air Force Space Technology Program (STP-2) mission.

For more information about DSAC visit

Related links:

SCaN (Space Communications and Navigation):

Space Travel:

Deep Space Network:

Deep Space Atomic Clock (DSAC):

Images (mentioned), Text, Credits: NASA/Sara Blumberg/Goddard Space Flight Center, by Danny Baird.


SpaceX - Falcon Heavy Test Flight Success

SpaceX - Falcon Heavy Test Flight patch.

Feb. 6, 2018

Falcon Heavy Test Flight lift off

The first test flight of Falcon Heavy lift off today at 3:45 PM ET from Launch Complex 39A at Kennedy Space Center in Florida.

Falcon Heavy Test Flight

When Falcon Heavy lifts off, it will be the most powerful operational rocket in the world by a factor of two. With the ability to lift into orbit nearly 64 metric tons (141,000 lb)---a mass greater than a 737 jetliner loaded with passengers, crew, luggage and fuel--Falcon Heavy can lift more than twice the payload of the next closest operational vehicle, the Delta IV Heavy, at one-third the cost. Falcon Heavy draws upon the proven heritage and reliability of Falcon 9. SpaceX's First Falcon Heavy Rocket Launches Tesla Electric Car to Leave Earth.

Image above: A “Starman” in a red Roadster: SpaceX’s Tesla Roadster and spacesuited mannequin driver set to launch on the company’s first Falcon Heavy rocket.

Falcon Heavy at the Launch Complex 39A

Falcon Heavy's first stage is composed of three Falcon 9 nine-engine cores whose 27 Merlin engines together generate more than 5 million pounds of thrust at liftoff, equal to approximately eighteen 747 aircraft. Only the Saturn V moon rocket, last flown in 1973, delivered more payload to orbit. Falcon Heavy was designed from the outset to carry humans into space and restores the possibility of flying missions with crew to the Moon or Mars.

For more infornation about SpaceX, visit:

Images, Video, Text, Credits: SpaceX/ Aerospace.


Space Station Science Highlights: Week of Jan. 29, 2018

ISS - Expedition 54 Mission patch.

Feb. 6, 2018

Last week, the crew living and working aboard the International Space Station had a busy week of science and spacewalk preparations, as well as an early Friday morning spacewalk for Russian crew members.

Image above: NASA astronaut Joe Acaba works with the SPHERES satellite as part of the SmoothNav investigation. Image Credit: NASA.

Crew members explored research in the fields of physical science, technology demonstrations and human research. Take a more detailed look at some of the science that happened last week aboard your orbiting laboratory:

Crew prepares ELF for upcoming operations

The Electrostatic Levitation Furnace (ELF) is an experimental facility designed to levitate, melt and solidify materials by container-less processing techniques using the electrostatic levitation method. With this facility, properties of high temperature melts can be measured, and solidification from deeply undercooled melts can be achieved.

Animation above: NASA astronauts Joe Acaba and Mark Vande Hei prepared for the SmoothNav investigation last week. This investigation develops an estimation algorithm aggregating relative state measurements between multiple, small, and potentially differently instrumented spacecraft. Animation Credit: NASA.

Last week, the crew moved samples to prepare for upcoming ground commandedoperations. Results from this investigation may contribute to the development of containerless processing technology, benefiting manufacturers and scientists designing new materials.

Crew conducts trial run for SmoothNav investigation

Many future space exploration and space-based business enterprise models, such as on-orbit satellite servicing, on-orbit assembly, and orbital debris removal, necessitate the use of fully autonomous multi-satellite systems. Smoothing-Based Relative Navigation (SmoothNav) develops an estimation algorithm aggregating relative state measurements between multiple, small, and potentially differently-instrumented spacecraft.

Space to Ground: Russian Spacewalk: 02/02/2018

The algorithm obtains the most probable estimate of the relative positions and velocities between all spacecraft using all available sensor information, including past measurements. The algorithm remains portable between different satellite platforms with different onboard sensors, adaptable in the case that one or more satellites become inoperable, and tolerant to delayed measurements or measurements received at different frequencies.

Last week, the crew set up the work area to activate and check out the hardware before conducting a trial run.

Investigation tests lighting aboard space station

Anyone who uses electric lights can benefit from lights that can be adjusted for intensity and wavelength across the day, improving alertness during waking hours and promoting sleep during evening hours. The Lighting Effects investigation studies the impact of the change from fluorescent light bulbs to solid-state light-emitting diodes (LEDs) with adjustable intensity and color and aims to determine if the new lights can improve crew circadian rhythms, sleep and cognitive performance.

Cosmonauts Alexander Misurkin (left) and Anton Shkaplerov are pictured in their Russian Orlan spacesuits during a fit check ahead of a Feb.2 spacewalk for International Space Station maintenance. Image Credit: NASA.

Last week, the crew conducted a visual performance test by stowing the hardware in their crew quarters, setting the light to the correct mode, turning all other light sources in the crew quarters off, and performing a color discrimination test.

Other work was done on these investigations: Personal CO2 Monitor,  Rodent Research-6, ACE-T-6, Two-Phase Flow, Plant Gravity Perception, At Home in Space, Space Headaches, Crew Earth Observations, ACME, TSIS, CBEF, Tropical Cyclone, Microbial Tracking-2, DOSIS-3D, MagVector, Transparent Alloys and DreamXCG.

Related links:

Electrostatic Levitation Furnace (ELF):

Lighting Effects:

Personal CO2 Monitor:

Rodent Research-6:


Two-Phase Flow:

Plant Gravity Perception:

At Home in Space:

Space Headaches:

Crew Earth Observations:




Tropical Cyclone:

Microbial Tracking-2:



Transparent Alloys:


Space Station Research and Technology:

International Space Station (ISS):

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


TRAPPIST-1 Planets Probably Rich in Water

ESO - European Southern Observatory logo.

6 February 2018

First glimpse of what Earth-sized exoplanets are made of

Artist’s impressions of the TRAPPIST-1 planetary system

A new study has found that the seven planets orbiting the nearby ultra-cool dwarf star TRAPPIST-1 are all made mostly of rock, and some could potentially hold more water than Earth. The planets' densities, now known much more precisely than before, suggest that some of them could have up to 5 percent of their mass in the form of water — about 250 times more than Earth's oceans. The hotter planets closest to their parent star are likely to have dense steamy atmospheres and the more distant ones probably have icy surfaces. In terms of size, density and the amount of radiation it receives from its star, the fourth planet out is the most similar to Earth. It seems to be the rockiest planet of the seven, and has the potential to host liquid water.

Artist’s impressions of the TRAPPIST-1 planetary system

Planets around the faint red star TRAPPIST-1, just 40 light-years from Earth, were first detected by the TRAPPIST-South telescope at ESO’s La Silla Observatory in 2016. In the following year further observations from ground-based telescopes, including ESO’s Very Large Telescope and NASA’s Spitzer Space Telescope, revealed that there were no fewer than seven planets in the system, each roughly the same size as the Earth. They are named TRAPPIST-1b,c,d,e,f,g and h, with increasing distance from the central star [1].

Artist’s impressions of the TRAPPIST-1 planetary system

Further observations have now been made, both from telescopes on the ground, including the nearly-complete SPECULOOS facility at ESO’s Paranal Observatory, and from NASA’s Spitzer Space Telescope and the Kepler Space Telescope.  A team of scientists led by Simon Grimm at the University of Bern in Switzerland have now applied very complex computer modelling methods to all the available data and have determined the planets’ densities with much better precision than was possible before [2].

The ultracool dwarf star TRAPPIST-1 in the constellation of Aquarius

Simon Grimm explains how the masses are found: "The TRAPPIST-1 planets are so close together that they interfere with each other gravitationally, so the times when they pass in front of the star shift slightly. These shifts depend on the planets' masses, their distances and other orbital parameters. With a computer model, we simulate the planets' orbits until the calculated transits agree with the observed values, and hence derive the planetary masses."

The sizes, masses and temperatures of the seven TRAPPIST-1 planets and others

Team member Eric Agol comments on the significance: "A goal of exoplanet studies for some time has been to probe the composition of planets that are Earth-like in size and temperature. The discovery of TRAPPIST-1 and the capabilities of ESO’s facilities in Chile and the NASA Spitzer Space Telescope in orbit have made this possible — giving us our first glimpse of what Earth-sized exoplanets are made of!"

Properties of the seven TRAPPIST-1 planets compared to other known planets

The measurements of the densities, when combined with models of the planets’ compositions, strongly suggest that the seven TRAPPIST-1 planets are not barren rocky worlds. They seem to contain significant amounts of volatile material, probably water [3], amounting to up to 5% the planet's mass in some cases — a huge amount; by comparison the Earth has only about 0.02% water by mass!

Properties of the seven TRAPPIST-1 planets

"Densities, while important clues to the planets' compositions, do not say anything about habitability. However, our study is an important step forward as we continue to explore whether these planets could support life," said Brice-Olivier Demory, co-author at the University of Bern.

Comparison of the properties of the seven TRAPPIST-1 planets

TRAPPIST-1b and c, the innermost planets, are likely to have rocky cores and be surrounded by atmospheres much thicker than Earth's. TRAPPIST-1d, meanwhile, is the lightest of the planets at about 30 percent the mass of Earth. Scientists are uncertain whether it has a large atmosphere, an ocean or an ice layer.

Comparison of the TRAPPIST-1 system and the Solar System

Scientists were surprised that TRAPPIST-1e is the only planet in the system slightly denser than Earth, suggesting that it may have a denser iron core and that it does not necessarily have a thick atmosphere, ocean or ice layer. It is mysterious that TRAPPIST-1e appears to be so much rockier in its composition than the rest of the planets. In terms of size, density and the amount of radiation it receives from its star, this is the planet that is most similar to Earth.

TRAPPIST-1f, g and h are far enough from the host star that water could be frozen into ice across their surfaces. If they have thin atmospheres, they would be unlikely to contain the heavy molecules that we find on Earth, such as carbon dioxide.

Planet Parade: the seven planets of TRAPPIST-1

"It is interesting that the densest planets are not the ones that are the closest to the star, and that the colder planets cannot harbour thick atmospheres," notes Caroline Dorn, study co-author based at the University of Zurich, Switzerland.

The TRAPPIST-1 system will continue to be a focus for intense scrutiny in the future with many facilities on the ground and in space, including ESO’s Extremely Large Telescope and the NASA/ESA/CSA James Webb Space Telescope.

Astronomers are also working hard to search for further planets around faint red stars like TRAPPIST-1. As team member Michaël Gillon explains [4]: "This result highlights the huge interest of exploring nearby ultracool dwarf stars — like TRAPPIST-1 — for transiting terrestrial planets. This is exactly the goal of SPECULOOS, our new exoplanet search that is about to start operations at ESO’s Paranal Observatory in Chile.”


[1] The planets were discovered using the ground-based TRAPPIST-South at ESO’s La Silla Observatory in Chile; TRAPPIST-North in Morocco; the orbiting NASA Spitzer Space Telescope; ESO’s HAWK-I instrument on the Very Large Telescope at the Paranal Observatory in Chile; the 3.8-metre UKIRT in Hawaii; the 2-metre Liverpool and 4-metre William Herschel telescopes on La Palma in the Canary Islands; and the 1-metre SAAO telescope in South Africa.

[2] Measuring the densities of exoplanets is not easy. You need to find out both the size of the planet and its mass. The TRAPPIST-1 planets were found using the transit method — by searching for small dips in the brightness of the star as a planet passes across its disc and blocks some light. This gives a good estimate of the planet’s size. However, measuring a planet’s mass is harder — if no other effects are present planets with different masses have the same orbits and there is no direct way to tell them apart. But there is a way in a multi-planet system — more massive planets disturb the orbits of the other planets more than lighter ones. This in turn affects the timing of transits. The team led by Simon Grimm have used these complicated and very subtle effects to estimate the most likely masses for all seven planets, based on a large body of timing data and very sophisticated data analysis and modelling.

[3] The models used also consider alternative volatiles, such as carbon dioxide. However, they favour water, as vapour, liquid or ice, as the most likely largest component of the planets’ surface material as water is the most abundant source of volatiles for solar abundance protoplanetary discs.

[4] The SPECULOOS survey telescopes facility is nearly complete at ESO’s Paranal Observatory.

More information:

This research was presented in a paper entitled “The nature of the TRAPPIST-1 exoplanets”, by S. Grimm et al., to appear in the journal Astronomy & Astrophysics.

The team is composed of Simon L. Grimm (University of Bern, Center for Space and Habitability, Bern, Switzerland) , Brice-Olivier Demory (University of Bern, Center for Space and Habitability, Bern, Switzerland), Michaël Gillon (Space Sciences, Technologies and Astrophysics Research Institute, Université de Liège, Liège, Belgium), Caroline Dorn (University of Bern, Center for Space and Habitability, Bern, Switzerland; University of Zurich, Institute of Computational Sciences, Zurich, Switzerland), Eric Agol (University of Washington, Seattle, Washington, USA; NASA Astrobiology Institute’s Virtual Planetary Laboratory, Seattle, Washington, USA; Institut d’Astrophysique de Paris, Paris, France), Artem Burdanov (Space Sciences, Technologies and Astrophysics Research Institute, Université de Liège, Liège, Belgium), Laetitia Delrez (Cavendish Laboratory, Cambridge, UK; Space Sciences, Technologies and Astrophysics Research Institute, Université de Liège, Liège, Belgium), Marko Sestovic (University of Bern, Center for Space and Habitability, Bern, Switzerland), Amaury H.M.J. Triaud (Institute of Astronomy, Cambridge, UK; University of Birmingham, Birmingham, UK), Martin Turbet (Laboratoire de Météorologie Dynamique, IPSL, Sorbonne Universités, UPMC Univ Paris 06, CNRS, Paris, France), Émeline Bolmont (Université Paris Diderot, AIM, Sorbonne Paris Cité, CEA, CNRS, Gif-sur-Yvette, France), Anthony Caldas (Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, Pessac, France), Julien de Wit (Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA), Emmanuël Jehin (Space Sciences, Technologies and Astrophysics Research Institute, Université de Liège, Liège, Belgium), Jérémy Leconte (Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, Pessac, France), Sean N. Raymond (Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, Pessac, France), Valérie Van Grootel (Space Sciences, Technologies and Astrophysics Research Institute, Université de Liège, Liège, Belgium), Adam J. Burgasser (Center for Astrophysics and Space Science, University of California San Diego, La Jolla, California, USA), Sean Carey (IPAC, Calif. Inst. of Technology, Pasadena, California, USA), Daniel Fabrycky (Department of Astronomy and Astrophysics, Univ. of Chicago, Chicago, Illinois, USA), Kevin Heng (University of Bern, Center for Space and Habitability, Bern, Switzerland), David M. Hernandez (Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA), James G. Ingalls (IPAC, Calif. Inst. of Technology, Pasadena, California, USA), Susan Lederer (NASA Johnson Space Center, Houston, Texas, USA), Franck Selsis (Laboratoire d’astrophysique de Bordeaux, Univ. Bordeaux, CNRS, Pessac, France) and Didier Queloz (Cavendish Laboratory, Cambridge, UK).

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

Related article:

New Clues to TRAPPIST-1 Planet Compositions, Atmospheres


ESOcast 150 Light: Planets around TRAPPIST-1 Probably Rich in Water:

Research paper:

Link to Hubble release on atmospheres of TRAPPIST-1 planets:

More information about TRAPPIST-South:

More information about SPECULOOS:

NASA’s Spitzer Space Telescope:

NASA’s Kepler Space Telescope:

ESO's Very Large Telescope (VLT):

Images, Graphics, Video, Text, Credits: ESO/Richard Hook/M. Kornmesser/SAINT-EX Research Group, University of Bern, Center for Space and Habitability/Brice-Olivier Demory/Simon Grimm/IAU and Sky & Telescope/NASA/JPL-Caltech/R. Hurt, T. Pyle (IPAC).

Best regards,