vendredi 27 avril 2018

Astronauts and Robotics Controllers Prepping Dragon for Departure

ISS - Expedition 55 Mission patch.

April 27, 2018

Image above: Houston, Texas, the home of NASA’s Johnson Space Center, and Galveston Bay are pictured from the space station at an altitude of about 250 miles. Image Credit: NASA.

Robotics controllers and Expedition 55 crew members are getting ready for the departure of the SpaceX Dragon resupply ship next week. The commercial space freighter will leave the International Space Station and splashdown in the Pacific Ocean on Wednesday loaded with cargo for retrieval and analysis.

Flight Engineer Ricky Arnold powered up command and communications gear today that will aid the crew when Dragon departs the station on Wednesday at 10:22 a.m. EDT. NASA TV will begin its live coverage of the departure activities at 10 a.m. Dragon will splashdown in the Pacific Ocean about six hours later to be recovered by SpaceX and NASA personnel. The splashdown off the southern coast of California will not be seen on NASA TV.

Image above: SpaceX's Dragon cargo craft arrived at the International Space Station April 4, 2018, on the company's 14th station resupply mission. After delivering more than 5,800 pounds of science investigations and crew supplies, the Dragon is scheduled to depart the station May 2, 2018, returning to Earth with more than 4,000 pounds of cargo, including science samples from human and animal research, biology and biotechnology studies, physical science investigations and education activities. Image Credit: NASA.

The Canadarm2 will be remotely maneuvered today to grapple Dragon today while it is still attached to the Harmony module. In the meantime the 57.7-foot-long robotic arm and its fine-tuned robotic hand, also known as Dextre, are completing the installation of an external materials exposure experiment outside of Japan’s Kibo laboratory module.

Image above: Flying over Gulf of Saint-Laurent, Canada, seen by EarthCam on ISS, speed: 27'617 Km/h, altitude: 420,57 Km, image captured by Roland Berga (on Earth in Switzerland) from International Space Station (ISS) using ISS-HD Live application with EarthCam's from ISS on April 27, 2018 at 14:42 UTC.

Astronauts Drew Feustel and Scott Tingle are still packing Dragon today with a variety of cargo including space station hardware and research samples. The STaARS-1 experiment facility has completed a year of operations at the station and is being readied for its return aboard Dragon next week. The research device supported observations of living systems exposed to simulated gravity such as Earth, the Moon and Mars. Feustel also stowed faulty life support gear in Dragon for refurbishment back on Earth.

Related links:

Materials exposure experiment:

STaARS-1 experiment facility:

SpaceX Dragon:


Expedition 55:

Space Station Research and Technology:

International Space Station (ISS):

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

Best regards,

ExoMars returns first images from new orbit

ESA & ROSCOSMOS - ExoMars Mission patch.

27 April 2018

ExoMars images Korolev Crater

The ExoMars Trace Gas Orbiter has returned the first images of the Red Planet from its new orbit.

The spacecraft arrived in a near-circular 400 km altitude orbit a few weeks ago ahead of its primary goal to seek out gases that may be linked to active geological or biological activity on Mars.

The orbiter’s Colour and Stereo Surface Imaging System, CaSSIS, took this stunning image, which features part of an impact crater, during the instrument’s test period. The camera was activated on 20 March and was tested for the start of its main mission on 28 April.

“We transmitted new software to the instrument at the start of the test phase and after a couple of minor issues, the instrument is in good health and ready to work,” says the camera’s principal investigator, Nicolas Thomas from the University of Bern in Switzerland.

The image captures a 40 km-long segment of Korolev Crater located high in the northern hemisphere. The bright material on the rim of the crater is ice.

“We were really pleased to see how good this picture was given the lighting conditions,” says Antoine Pommerol, a member of the CaSSIS science team working on the calibration of the data. “It shows that CaSSIS can make a major contribution to studies of the carbon dioxide and water cycles on Mars.”

The image is assembled from three images in different colours that were taken almost simultaneously on 15 April.

“We aim to fully automate the image production process,” says Nick. “Once we achieve this, we can distribute the data quickly to the science community for analysis.”

The team also plans to make regular public releases.

The orbiter’s camera is one of four instruments on the Trace Gas Orbiter, or TGO, which also hosts two spectrometer suites and a neutron detector.

The spectrometers began their science mission on 21 April with the spacecraft taking its first ‘sniff’ of the atmosphere. In reality, the sniffing is the spectrometers looking at how molecules in the atmosphere absorb sunlight: each has a unique fingerprint that reveals its chemical composition.

A long period of data collection will be needed to bring out the details, especially for particularly rare – or not even yet discovered – ingredients in the atmosphere. Trace gases, as hinted at from their name, are only present in very small amounts: that is, less than one percent of the volume of the planet’s atmosphere. In particular, the orbiter will seek evidence of methane and other gases that could be signatures of active biological or geological activity.

The camera will eventually help characterise features on the surface that may be related to trace gas sources.

“We are excited to finally be starting collecting data at Mars with this phenomenal spacecraft,” says Håkan Svedhem, ESA’s TGO project scientist. “The test images we have seen so far certainly set the bar high.”

Trace Gas Orbiter at Mars

The ExoMars programme is a joint endeavour between ESA and Roscosmos. The Trace Gas Orbiter is the first of two missions in the programme: the next is scheduled for launch in 2020 and will comprise a rover and a surface science platform. TGO will act as a communication relay for both. It proved this capability earlier this week in the first of a series of relay communications with NASA’s Curiosity rover, highlighting the cooperation between ESA and NASA to maintain a communications infrastructure around Mars for future missions.

Related links:


Robotic exploration of Mars:


ExoMars at IKI:

Thales Alenia Space:

NASA In 2016 ExoMars orbiter (Electra radio):

Where on Mars?:

Images, Text, Credits: ESA/Markus Bauer/Håkan Svedhem/University of Bern/Nicolas Thomas/Roscosmos/CaSSIS/ATG medialab.

Best regards,

jeudi 26 avril 2018

CASC - Long March 11 launches multiple satellites

CASC - China Aerospace Science and Technology Corporation logo.

April 26, 2018

Long March-11 rocket carrying multiple satellites launch. Image Credit: CASC

China launched its fourth Long March-11 rocket on Thursday, carrying a multiple small satellites into orbit. The launch took place from a mobile launch platform from the Jiuquan Satellite Launch Center at 04:42 UTC.

Onboard the LM-11 rocket was the OVS-2 upgraded version of Zhuhai-1 video satellite and four hyperspectral satellites from the OHS-2s series.

Long March-11 launches five Zhuhai-1 satellites

Developed by the Zhuhai Obit Space Science and Technology Co., Ltd., the Zhuhai-1 earth observation satellites are the video component of the Chinese Orbital earth observation system. Two OVS-1 (OVS-1a and OVS-1b) satellites launched on June 16, 2017, constituted the prototype OVS-1 video component of the system. The operational Orbita constellation is to consist of video satellites (OVS-2), hyperspectral satellites (OHS-2) and small personal satellites (OPS-2).

The new up upgraded version of the previously launched video satellites has a resolution of 0.9 meters, which will greatly improve the spatial resolution and data acquisition capabilities of the previous satellites orbited in the system (with a resolution of 1.98 meters). Images obtained cover an area of 25km x 2.7km, approximately 67.5 square kilometers.

Zhuhai-1 (OVS-1). Image Credit: Zhuhai Orbita

The four new hyperspectral satellites have a resolution of 10 meters. This is the first-generation of hyperspectral satellites launched by private enterprises in China, having a broad market potential. Images obtained cover an area of 140km×0.24km, approximately 33.6 square kilometers. The four satellites have a global coverage once every five days.

The OHS-1-01 satellite is also known as ‘Qingkeda-1’ and was developed in cooperation with the Qingdao University of Science and Technology. The OHS-1-03 satellite is also known as ‘Guiyang-1’.

For more information about China Aerospace Science and Technology Corporation (CASC), visit:

For more information about China National Space Administration (CNSA), visit:

Images (mentioned), Video, Text, Credits: NASA C. Barbosa/SciNews/Günter Space Page.


Astronauts Explore Life Science and Prepare for Spacewalk

ISS - Expedition 55 Mission patch.

April 26, 2018

A wide variety of life science is being explored today aboard the International Space Station as Expedition 55 crew members prepare for a spacewalk planned for next month. The space residents also continued the upkeep of the orbital lab while robotics controllers set up an external experiment.

Japanese astronaut Norishige Kanai split his time today between tending mice and removing sensors attached to his arm. The rodents are being observed to detect the chemical signals that lead to muscle and bone loss in space and to provide therapies to keep astronauts healthy. Kanai also removed an armband monitor and sensors he wore for 36 hours that recorded alterations in his circadian rhythm caused by living in space.

Image above: NASA astronaut Scott Tingle prepares video equipment for a series of education videos being recorded for the STEMonstration campaign which demonstrates scientific concepts in space for students and teachers. Image Credit: NASA.

Flight Engineers Ricky Arnold and Drew Feustel are getting ready for a May 16 spacewalk to swap out thermal control gear that circulates ammonia to keep station systems cool. The duo readied their spacewalk tools today then dumped water and purged gases from a pair of U.S. spacesuits.

Scott Tingle of NASA worked inside the Harmony module today to replace a deteriorating Pump Package Assembly (PPA) with a spare device. The PPA is a thermal control system that provides water cooling to station payloads and critical systems avionics.

Image above: This view from above the nation of Turkey looks out across the Aegean Sea, over Greece and onto the Ionian Sea where Sicily and the boot of Italy are barely visible. The sun's glint on the Mediterranean waters highlight the Greek islands while clouds cloak the island of Crete. This Earth observation image was taken by a member of the Expedition 55 crew aboard the International Space Station on April 2, 2018. Image Credit: NASA.

Science is also taking place outside the space station and robotics controllers are working to transfer a tray for the materials exposure experiment (MISSE-FF) outside of the Kibo lab module through the lab’s airlock for reconfiguration tomorrow. The complex robotic maneuvers are remotely controlled from the ground and use not only the Canadarm2 robotic arm but also the fine-tuning robotic hand known as Dextre. MISSE-FF will test materials, coatings, and components in the harsh environment of space.

Also, overnight, Russian flight controllers sent commands to deorbit the unpiloted ISS Progress 68 cargo craft that had been orbiting for the past month for engineering test following its undocking from the station March 28. It burned up harmlessly in the Earth’s atmosphere over the southern Pacific.

Related links:

Circadian rhythm:


Expedition 55:

Space Station Research and Technology:

International Space Station (ISS):

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

Best regards,

Before the Flood Arrives

NASA logo.

April 26, 2018

New NASA Study May Improve Future River-Observing Satellites

River floods are one of the most common and devastating of Earth’s natural disasters. In the past decade, deluges from rivers have killed thousands of people every year around the world and caused losses on the order of tens of billions of U.S. dollars annually. Climate change, which is projected to increase precipitation in certain areas of the planet, might make river floods in these places more frequent and severe in the coming decades.

Now, a new study led by researchers at NASA’s Jet Propulsion Laboratory in Pasadena, California, analyzes what it would take for river-observing satellites to become an even more useful tool to mitigate flood damage and improve reservoir management globally in near real-time.

Image above: Artist’s illustration of NASA’s planned Surface Water and Ocean Topography (SWOT) satellite over the Amazon basin. The colors depict estimated minimum times for flood waves to travel downstream and reach the ocean, data that can inform requirements of satellites like SWOT that can detect floods. Image Credits: NASA/JPL-Caltech.

“Early flood warning systems traditionally depend on gauge networks that detect floods farther up the river, but gauge data are becoming more and more scarce," said George Allen, lead author of the new research and a hydrologist at JPL. “Our study shows that there’s room for satellites to help fill in the gap. But for satellites to inform real-time flood mitigation, they have to provide data to water managers within a sufficiently short lag time.”

River floods occur when a channel fills with water beyond the capacity of its banks, normally due to heavy rainfall. The flood travels along the course of the river as a wave, moving downstream faster than the water itself. Several satellite missions have been able to detect floods as sudden changes in the height or width of river waters. Once a flood is observed, it is relatively easy to predict accurately how it will move down the river. This information is extremely useful in early flood warning systems and other real-time river management applications.

To study the speed at which floods propagate through the planet’s rivers, Allen and his colleagues ran a simple numerical model of flow waves that used information such as the width, slope, depth and roughness -- the amount of friction water experiences when traveling along a river -- of rivers worldwide. After analyzing wave speeds through 11 million miles (17.7 million kilometers) of rivers around the planet, the researchers found that flood waves traveling at their maximum speed take a median time of three days to reach the next downstream dam, four days to arrive to the next downstream city and six days to exit the river system entirely.

Image above: Global map of the minimum times it takes flood waves to exit the global river network. Such information can be used to develop data requirements for satellites that can detect floods, for applications in making real-time river management decisions. Image Credits: NASA/JPL-Caltech.

The team compared their model’s results with discharge records from more than 20,000 U.S. Geological Survey gauge stations along around 40,000 miles (64,400 kilometers) of varied river systems in the United States. They found that the model estimated faster wave speeds than the gauge data showed.

“That was expected, based on the fact that we’re modeling waves moving at maximum speeds, whereas the gauge data are looking at all types of wave speeds: low speeds, high speeds, everything in between,” Allen said. “In this way, our study estimates a worst-case-scenario of how fast floods can move down rivers.”

The scientists then used their wave speed findings to calculate data latency -- how quickly satellite data should be downloaded, processed and made available to the public to be useful for flood early warning systems and other real-time flood mitigation strategies, as well as reservoir management. In particular, they focused on future data from NASA’s upcoming Surface Water and Ocean Topography (SWOT) mission. SWOT, scheduled to launch in 2021, is specifically designed to observe rivers. That’s because it has a repeat orbit of 21 days and will be able to detect flood waves, particularly in higher-latitude large rivers. The researchers found that making SWOT data available within days after being acquired by the spacecraft could be useful for real-time flood mitigation. Compared to past or current satellites providing river and flood information, SWOT will provide never-before-seen maps of river height, allowing for more reliable prediction of flood timing and magnitude.

If the data were to be processed in two days or less, Allen’s team calculated, it would be ready for emergency managers before at least two-thirds of observed waves reached the next downstream city. For dams, the quick turnaround of satellite measurements would give advance notice to downstream reservoirs in at least half of the cases when  SWOT detects a flood wave. 

“There is a trade-off between data latency and data quality,” said Cédric David of JPL, who directed the new study and is a member of SWOT’s science team. “So, do we want to wait to get the best data possible, or do we want to get a rough version of what’s going on now, so we can provide actionable information? As we prepare for new satellite missions like SWOT, that’s when we start asking these types of questions.”

Satellite data that could inform flood early warning systems would be particularly useful for developing nations, where either there are insufficient river gauges or countries do not share gauge data with their downstream neighbors, Allen said.

Results of the study are published in the journal Geophysical Research Letters:

For more information on SWOT, visit:

Images (mentioned), Text, Credits: NASA/Tony Greicius/JPL/Alan Buis/NASA’s Earth Science News Team, written by Maria-José Viñas.


Stellar Thief Is the Surviving Companion to a Supernova

NASA - Hubble Space Telescope patch.

April 26, 2018

Seventeen years ago, astronomers witnessed a supernova go off 40 million light-years away in the galaxy called NGC 7424, located in the southern constellation Grus, the Crane. Now, in the fading afterglow of that explosion, NASA's Hubble Space Telescope has captured the first image of a surviving companion to a supernova. This picture is the most compelling evidence that some supernovas originate in double-star systems.

“We know that the majority of massive stars are in binary pairs,” said Stuart Ryder from the Australian Astronomical Observatory (AAO) in Sydney, Australia, and lead author of the study. “Many of these binary pairs will interact and transfer gas from one star to the other when their orbits bring them close together.”

Image above: Seventeen years ago, astronomers witnessed supernova 2001ig go off 40 million light-years away in the galaxy NGC 7424, in the southern constellation Grus, the Crane. Shortly after, scientists photographed the supernova with the European Southern Observatory’s Very Large Telescope (VLT) in 2002. Two years later, they followed up with the Gemini South Observatory, which hinted at the presence of a surviving binary companion. As the supernova’s glow faded, scientists focused Hubble on that location in 2016. They pinpointed and photographed the surviving companion, which was possible only due to Hubble’s exquisite resolution and ultraviolet sensitivity. Hubble observations of SN 2001ig provide the best evidence yet that some supernovas originate in double-star systems. Image Credits: NASA, ESA, S. Ryder (Australian Astronomical Observatory), and O. Fox (STScI).

The companion to the supernova’s progenitor star was no innocent bystander to the explosion. It siphoned off almost all of the hydrogen from the doomed star’s stellar envelope, the region that transports energy from the star’s core to its atmosphere. Millions of years before the primary star went supernova, the companion’s thievery created an instability in the primary star, causing it to episodically blow off a cocoon and shells of hydrogen gas before the catastrophe.

The supernova, called SN 2001ig, is categorized as a Type IIb stripped-envelope supernova. This type of supernova is unusual because most, but not all, of the hydrogen is gone prior to the explosion. This type of exploding star was first identified in 1987 by team member Alex Filippenko of the University of California, Berkeley.

How stripped-envelope supernovas lose that outer envelope is not entirely clear. They were originally thought to come from single stars with very fast winds that pushed off the outer envelopes. The problem was that when astronomers started looking for the primary stars from which supernovas were spawned, they couldn’t find them for many stripped-envelope supernovas.

“That was especially bizarre, because astronomers expected that they would be the most massive and the brightest progenitor stars,” explained team member Ori Fox of the Space Telescope Science Institute in Baltimore. “Also, the sheer number of stripped-envelope supernovas is greater than predicted.” That fact led scientists to theorize that many of the primary stars were in lower-mass binary systems, and they set out to prove it.

Looking for a binary companion after a supernova explosion is no easy task. First, it has to be at a relatively close distance to Earth for Hubble to see such a faint star. SN 2001ig and its companion are about at that limit. Within that distance range, not many supernovas go off. Even more importantly, astronomers have to know the exact position through very precise measurements.

In 2002, shortly after SN 2001ig exploded, scientists pinpointed the precise location of the supernova with the European Southern Observatory’s Very Large Telescope (VLT) in Cerro Paranal, Chile. In 2004, they then followed up with the Gemini South Observatory in Cerro Pachón, Chile. This observation first hinted at the presence of a surviving binary companion.

Knowing the exact coordinates, Ryder and his team were able to focus Hubble on that location 12 years later, as the supernova’s glow faded. With Hubble’s exquisite resolution and ultraviolet capability, they were able to find and photograph the surviving companion—something only Hubble could do.

Prior to the supernova explosion, the orbit of the two stars around each other took about a year.

When the primary star exploded, it had far less impact on the surviving companion than might be thought. Imagine an avocado pit—representing the dense core of the companion star—embedded in a gelatin dessert—representing the star’s gaseous envelope. As a shock wave passes through, the gelatin might temporarily stretch and wobble, but the avocado pit would remain intact.

In 2014, Fox and his team used Hubble to detect the companion of another Type IIb supernova, SN 1993J. However, they captured a spectrum, not an image. The case of SN 2001ig is the first time a surviving companion has been photographed. “We were finally able to catch the stellar thief, confirming our suspicions that one had to be there,” said Filippenko.

Hubble Space Telescope (HST). Animation Credits:ESA/NASA

Perhaps as many as half of all stripped-envelope supernovas have companions—the other half lose their outer envelopes via stellar winds. Ryder and his team have the ultimate goal of precisely determining how many supernovas with stripped envelopes have companions.

Their next endeavor is to look at completely stripped-envelope supernovas, as opposed to SN 2001ig and SN 1993J, which were only about 90 percent stripped. These completely stripped-envelope supernovas don’t have much shock interaction with gas in the surrounding stellar environment, since their outer envelopes were lost long before the explosion. Without shock interaction, they fade much faster. This means that the team will only have to wait two or three years to look for surviving companions.

In the future, they also hope to use the James Webb Space Telescope to continue their search.

The paper on this team’s current work was published on March 28, 2018, in the Astrophysical Journal:

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.

For NASA's Hubble webpage, visit:

For more images and information, visit:

For the science paper, visit:

Image (mentioned), Animation (mentioned), Text, Credits: NASA/Karl Hille/Space Telescope Science Institute/Ori Fox/Ann Jenkins/Ray Villard/Australian Astronomical Observatory/Stuart Ryder/University of California/Alex Filippenko.

Best regards,

Back to (Nucleic) Bases - Studying DNA aboard the International Space Station

ISS - International Space Station patch / Genes in Space logo.

April 26, 2018

Image above: The miniPCR is used for a variety of genetic investigations to help astronauts quickly amplify,or make copies of, a single DNA sequence. Image Credit: NASA.

What do astronauts, microbes, and plants all have in common? Each relies on deoxyribonucleic acid (DNA) – essentially a computer code for living things - to grow and thrive.

Studying DNA in space could lead to a better understanding of microgravity’s impact on living organisms and could also offer ways to identify unknown microbes in spacecraft, humans and the deep space locations we seek to visit. The microscopic size of DNA, however, can create some big challenges for studying it aboard the International Space Station.

Most Earth-based molecular research equipment is large in size and requires significant amounts of power to run. Those are two characteristics that can be difficult to support aboard the orbiting laboratory, so previous research samples requiring DNA amplification and sequencing had to be stored in space until they could be sent back to Earth aboard a cargo spacecraft, adding to the time required to get results.

Image above: NASA astronaut Ricky Arnold prepares the miniPCR for Genes in Space-5, a student designed investigation studying alterations in DNA that may lead to weakened immunity. Image Credit: NASA.

However, all of that has changed in a few short years as NASA has worked to find new solutions for rapid in-flight molecular testing aboard the space station.

“We need[ed] to get machines to be compact, portable, robust, and independent of much power generation to allow for more agile testing in space,” NASA astronaut and molecular biologist Kate Rubins said in a 2016 downlink with the National Institutes of Health.

The result? An advanced suite of tabletop and palm-sized tools including MinION, miniPCR, and Wet-Lab-2, and more tools and processes on the horizon.

Space-based DNA testing took off in 2016 with the Biomolecule Sequencer. Comprised of the MinION sequencer and a Surface Pro 3 tablet for analysis, the tool was used to sequence DNA in space for the first time with Rubins at the helm.

Image above: Astronaut Kate Rubins working with Wet Lab-2, a tool for quantitative gene expression analysis set for further testing this year. Image Credit: NASA.

In 2017, that tool was used again for Genes in Space-3, as NASA astronaut Peggy Whitson collected and tested samples of microbial growth from around the station. Alongside MinION, astronauts also tested miniPCR, a thermal cycler used to perform the polymerase chain reaction that had been downsized to fit workbenches aboard the space station. Together these platforms provided the identification of unknown station microbes for the first time from space.

This year, those testing capabilities translated into an even stronger portfolio of DNA-focused research for the orbiting laboratory’s fast-paced science schedule. For example, miniPCR is being used to test weakened immune systems and DNA alterations as part of a student-designed investigation known as Genes in Space-5. The study hopes to reveal more about astronaut health and potential stress-related changes to DNA created by spaceflight. Additionally, WetLab-2 facility is a suite of tools aboard the station designed to process biological samples for real-time gene expression analysis. More tools for filling out the complete molecular studies opportunities on the orbiting laboratory are heading to space soon.

“The mini revolution has begun,” said Sarah Wallace, NASA’s principal investigator for the upcoming Biomolecule Extraction and Sequencing Technology (BEST) investigation. “These are very small, efficient tools. We have a nicely equipped molecular lab on station and devices ideally sized for spaceflight.”

Image above: Microbiologist Sarah Stahl tests the BEST swab-to-sequence procedure in JSC Microbiology lab. Image Credit: Sarah Wallace.

BEST will compare swab-to-sequencer testing of unknown microbes aboard the space station against current culture-based methods.

“We see changes in gene expression in response to spaceflight for every living thing in which we have looked for it,” said Wallace. “Studying those changes is critical to understand adaptations to spaceflight and also provides the potential to discover novel responses that could result in alternative healthcare treatments on Earth.”

Cosmic Carpool: DNA To Go

While resupply and ground support are available for astronauts aboard the space station, missions beyond low-Earth orbit will require crews to rely on these new, space-saving technologies to track their health across time and to monitor potential health risks living alongside them. Fast, reliable sequencing and identification processes could keep explorers safer on missions into deep space. On Earth, these technologies may make genetic research more accessible, affordable and mobile.

Related links:




Biomolecule Sequencer:

Genes in Space-3:

Genes in Space-5:

Biomolecule Extraction and Sequencing Technology (BEST):

Space Station Research and Technology:

International Space Station (ISS):

Images, (mentioned), Video, Text, Credits: NASA/Michael Johnson/NASA Johnson/JSC/Morgan McAllister/Rachel Barry.


mercredi 25 avril 2018

Ancient Galaxy Megamergers

ALMA - Atacama Large Millimeter/submillimeter Array logo.

25 April 2018

 Artist’s impression of ancient galaxy megamerger

The ALMA and APEX telescopes have peered deep into space — back to the time when the Universe was one tenth of its current age — and witnessed the beginnings of gargantuan cosmic pileups: the impending collisions of young, starburst galaxies. Astronomers thought that these events occurred around three billion years after the Big Bang, so they were surprised when the new observations revealed them happening when the Universe was only half that age! These ancient systems of galaxies are thought to be building the most massive structures in the known Universe: galaxy clusters.

Using the Atacama Large Millimeter/submillimeter Array (ALMA) and the Atacama Pathfinder Experiment (APEX), two international teams of scientists led by Tim Miller from Dalhousie University in Canada and Yale University in the US and Iván Oteo from the University of Edinburgh, United Kingdom, have uncovered startlingly dense concentrations of galaxies that are poised to merge, forming the cores of what will eventually become colossal galaxy clusters.

Peering 90% of the way across the observable Universe, the Miller team observed a galaxy protocluster named SPT2349-56. The light from this object began travelling to us when the Universe was about a tenth of its current age.

The individual galaxies in this dense cosmic pileup are starburst galaxies and the concentration of vigorous star formation in such a compact region makes this by far the most active region ever observed in the young Universe. Thousands of stars are born there every year, compared to just one in our own Milky Way.

Images of a galaxy protocluster from SPT, APEX and ALMA

The Oteo team discovered a similar megamerger formed by ten dusty star-forming galaxies, nicknamed a “dusty red core” because of its very red colour, by combining observations from ALMA and the APEX.

Iván Oteo explains why these objects are unexpected: “The lifetime of dusty starbursts is thought to be relatively short, because they consume their gas at an extraordinary rate. At any time, in any corner of the Universe, these galaxies are usually in the minority. So, finding numerous dusty starbursts shining at the same time like this is very puzzling, and something that we still need to understand.”

These forming galaxy clusters were first spotted as faint smudges of light, using the South Pole Telescope and the Herschel Space Observatory. Subsequent ALMA and APEX observations showed that they had unusual structure and confirmed that their light originated much earlier than expected — only 1.5 billion years after the Big Bang.

The new high-resolution ALMA observations finally revealed that the two faint glows are not single objects, but are actually composed of fourteen and ten individual massive galaxies respectively, each within a radius comparable to the distance between the Milky Way and the neighbouring Magellanic Clouds.

Artist’s impression of ancient galaxy megamerger

"These discoveries by ALMA are only the tip of the iceberg. Additional observations with the APEX telescope show that the real number of star-forming galaxies is likely even three times higher. Ongoing observations with the MUSE instrument on ESO’s VLT are also identifying additional galaxies,” comments Carlos De Breuck, ESO astronomer.

Current theoretical and computer models suggest that protoclusters as massive as these should have taken much longer to evolve. By using data from ALMA, with its superior resolution and sensitivity, as input to sophisticated computer simulations, the researchers are able to study cluster formation less than 1.5 billion years after the Big Bang.

"How this assembly of galaxies got so big so fast is a mystery. It wasn’t built up gradually over billions of years, as astronomers might expect. This discovery provides a great opportunity to study how massive galaxies came together to build enormous galaxy clusters," says Tim Miller, a PhD candidate at Yale University and lead author of one of the papers.

More information:

This research was presented in two papers, “The Formation of a Massive Galaxy Cluster Core at z = 4.3”, by T. Miller et al., to appear in the journal Nature, and “An Extreme Proto-cluster of Luminous Dusty Starbursts in the Early Universe”, by I. Oteo et al., which appeared in the Astrophysical Journal.

The Miller team is composed of: T. B. Miller (Dalhousie University, Halifax, Canada; Yale University, New Haven, Connecticut, USA), S. C. Chapman (Dalhousie University, Halifax, Canada; Institute of Astronomy, Cambridge, UK), M. Aravena (Universidad Diego Portales, Santiago, Chile), M. L. N. Ashby (Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA), C. C. Hayward (Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA; Center for Computational Astrophysics, Flatiron Institute, New York, New York, USA), J. D. Vieira (University of Illinois, Urbana, Illinois, USA), A. Weiß (Max-Planck-Institut für Radioastronomie, Bonn, Germany), A. Babul (University of Victoria, Victoria, Canada) , M. Béthermin (Aix-Marseille Université, CNRS, LAM, Laboratoire d’Astrophysique de Marseille, Marseille, France), C. M. Bradford (California Institute of Technology, Pasadena, California, USA; Jet Propulsion Laboratory, Pasadena, California, USA), M. Brodwin (University of Missouri, Kansas City, Missouri, USA), J. E. Carlstrom (University of Chicago, Chicago, Illinois USA), Chian-Chou Chen (ESO, Garching, Germany), D. J. M. Cunningham (Dalhousie University, Halifax, Canada; Saint Mary’s University, Halifax, Nova Scotia, Canada), C. De Breuck (ESO, Garching, Germany), A. H. Gonzalez (University of Florida, Gainesville, Florida, USA), T. R. Greve (University College London, Gower Street, London, UK), Y. Hezaveh (Stanford University, Stanford, California, USA), K. Lacaille (Dalhousie University, Halifax, Canada; McMaster University, Hamilton, Canada), K. C. Litke (Steward Observatory, University of Arizona, Tucson, Arizona, USA), J. Ma (University of Florida, Gainesville, Florida, USA), M. Malkan (University of California, Los Angeles, California, USA) , D. P. Marrone (Steward Observatory, University of Arizona, Tucson, Arizona, USA), W. Morningstar (Stanford University, Stanford, California, USA), E. J. Murphy (National Radio Astronomy Observatory, Charlottesville, Virginia, USA), D. Narayanan (University of Florida, Gainesville, Florida, USA), E. Pass (Dalhousie University, Halifax, Canada), University of Waterloo, Waterloo, Canada), R. Perry (Dalhousie University, Halifax, Canada), K. A. Phadke (University of Illinois, Urbana, Illinois, USA), K. M. Rotermund (Dalhousie University, Halifax, Canada), J. Simpson (University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh; Durham University, Durham, UK), J. S. Spilker (Steward Observatory, University of Arizona, Tucson, Arizona, USA), J. Sreevani (University of Illinois, Urbana, Illinois, USA), A. A. Stark (Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA), M. L. Strandet (Max-Planck-Institut für Radioastronomie, Bonn, Germany) and A. L. Strom (Observatories of The Carnegie Institution for Science, Pasadena, California, USA).

The Oteo team is composed of: I. Oteo (Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, UK; ESO, Garching, Germany), R. J. Ivison (ESO, Garching, Germany; Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, UK), L. Dunne (Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, UK; Cardiff University, Cardiff, UK), A. Manilla-Robles (ESO, Garching, Germany; University of Canterbury, Christchurch, New Zealand), S. Maddox (Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, UK; Cardiff University, Cardiff, UK), A. J. R. Lewis (Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, UK), G. de Zotti (INAF-Osservatorio Astronomico di Padova, Padova, Italy), M. Bremer (University of Bristol, Tyndall Avenue, Bristol, UK), D. L. Clements (Imperial College, London, UK), A. Cooray (University of California, Irvine, California, USA), H. Dannerbauer (Instituto de Astrofíısica de Canarias, La Laguna, Tenerife, Spain; Universidad de La Laguna, Dpto. Astrofísica, La Laguna, Tenerife, Spain), S. Eales (Cardiff University, Cardiff, UK), J. Greenslade (Imperial College, London, UK), A. Omont (CNRS, Institut d’Astrophysique de Paris, Paris, France; UPMC Univ. Paris 06, Paris, France), I. Perez–Fournón (University of California, Irvine, California, USA; Instituto de Astrofísica de Canarias, La Laguna, Tenerife, Spain), D. Riechers (Cornell University, Space Sciences Building, Ithaca, New York, USA), D. Scott (University of British Columbia, Vancouver, Canada), P. van der Werf (Leiden Observatory, Leiden University, Leiden, The Netherlands), A. Weiß (Max-Planck-Institut für Radioastronomie, Bonn, Germany) and Z-Y. Zhang (Institute for Astronomy, University of Edinburgh, Royal Observatory, Edinburgh, UK; ESO, Garching, Germany).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It has 15 Member States: Austria, Belgium, 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 with 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”.


ESOcast 157 Light: Ancient Galaxy Pileups:

Research paper (Miller et al.):

Research paper (Oteo et al.):

Photos of APEX:

Photos of ALMA:

Atacama Large Millimeter/submillimeter Array (ALMA):

Atacama Pathfinder Experiment (APEX):

South Pole Telescope:

Herschel Space Observatory:

Images, Video, Text, Credits: ESO/M. Kornmesser/ALMA (ESO/NAOJ/NRAO)/Miller et al.


Seventh Sentinel satellite launched for Copernicus

ESA - Sentinel 3 Mission logo.

25 April 2018

Sentinel-3B liftoff

The second Sentinel-3 satellite, Copernicus Sentinel-3B, was launched today, joining its identical twin Sentinel-3A in orbit. This pairing of satellites increases coverage and data delivery for the European Union’s Copernicus environment programme.

The 1150 kg Sentinel-3B satellite was carried into orbit on a Rockot launcher from Plesetsk, Russia, at 17:57 GMT (19:57 CEST; 21:57 local time) on 25 April.

Sentinel-3B liftoff replay

Rockot’s upper stage delivered Sentinel-3B into its planned orbit.

Just 92 minutes after liftoff, Sentinel-3B sent its first signals to the Kiruna station in Sweden. Data links were quickly established by teams at ESA’s operations centre in Darmstadt, Germany, allowing them to assume control of the satellite.

During the three-day launch and the early orbit phase, controllers will check that all the satellite’s systems are working and begin calibrating the instruments to commission the satellite. The mission is expected to begin routine operations after five months.

“This is the seventh launch of a Sentinel satellite in the last four years. It is a clear demonstration of what European cooperation can achieve and it is another piece to operating the largest Earth observation programme in the world, together with our partners from the European Commission and Eumetsat,” said ESA Director General Jan Wörner.

Sentinel-3 in orbit

With this launch, the first set of Sentinel missions for the European Union’s Copernicus environmental monitoring network are in orbit, carrying a range of technologies to monitor Earth’s land, oceans and atmosphere.

ESA’s Director of Earth Observation Programmes, Josef Aschbacher, said, “With Sentinel-3B, Europe has put the first constellation of Sentinel missions into orbit – this is no small job and has required strong support by all involved. It allows us to get a very detailed picture of our planet on a daily basis and provides crucial information for policy makers.

“It also offers lots of opportunities for commercial companies to develop new innovative services. And, the free and open data policy allows every citizen to have updates for their own use.

“When we designed such a satellite constellation 20 years ago not everyone was convinced Europe could do that. I am glad to see this has become reality and that it is now a large European success story.”

Sentinel-3 scans Earth’s colour

Copernicus relies on the Sentinels and contributing missions to provide data for monitoring the environment and for supporting civil security activities. Sentinel-3 carries a series of cutting-edge sensors to do just that.

Over oceans, it measures the temperature, colour and height of the sea surface as well as the thickness of sea ice. These measurements are used, for example, to monitor changes in Earth’s climate and for more hands-on applications such as marine pollution.

Over land, this innovative mission monitors wildfires, maps the way land is used, checks vegetation health and measures the height of rivers and lakes.

Data from the Copernicus Programme are used worldwide and are free of charge.

Related links:


Sentinel data access:


Images, Video, Text, Credits: ESA/ATG medialab.

Best regards,

Space Gardening, Dragon Packing and Spacewalk Work Aboard Lab

ISS - Expedition 55 Mission patch.

April 25, 2018

The Expedition 55 crew is experimenting with space gardening today while packing research samples and cargo for return to Earth. The space residents are also breaking down gear brought in from last month’s spacewalk and getting ready for the next spacewalk.

Botany research aboard the International Space Station helps scientists and astronauts learn how to grow food off Earth to sustain future missions. Today’s space gardening work performed by Flight Engineer Drew Feustel will test the automated nourishment of lettuce and mizuna greens grown in the Veggie facility. The plants will be harvested and samples sent back to Earth for analysis.

Botanical samples are just one example of the multiple types of research and cargo that is sent to Earth packed inside the SpaceX Dragon cargo craft. Radiation monitors that recorded exposure levels in the station’s crew quarters were collected by Japanese astronaut Norishige Kanai today for stowage inside Dragon. Engineers on the ground will examine the radiation data and determine the exposure risk to the crew and develop countermeasures.

Image above: Astronauts Scott Tingle (left) and Ricky Arnold wrap up spacesuit work following a successful spacewalk on March 29, 2018. The duo scrubbed cooling loops, performed the iodination of ion filters and tested the water conductivity inside a pair of U.S. spacesuits. Image Credit: NASA.

NASA astronauts Scott Tingle and Ricky Arnold disassembled an external television camera group (ETVCG) brought in from last month’s spacewalk. Tingle then replaced a failed light bulb in a light to be used on another ETVCG which will be installed on the next spacewalk scheduled for mid-May. Parts from the old ETVCG will be shipped back to Earth in Dragon for refurbishment.

Dragon is due for two more work days of packing before its return to Earth next week. Ground controllers will remotely detach Dragon from the Harmony module before releasing it from the grips of Canadarm2 into space at 10:22 a.m. EDT Wednesday, May 2. Tingle will monitor the robotics activities as NASA TV broadcasts the departure activities live starting at 10 a.m. Splashdown in the Pacific Ocean is planned for 4:02 p.m. and will not be seen on NASA TV.

Related links:


SpaceX Dragon:

Expedition 55:

Space Station Research and Technology:

International Space Station (ISS):

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

Best regards,

Stellar Dust Survey Paves Way for Exoplanet Missions

NASA logo.

April 25, 2018

Image above: This artist’s illustration shows what the sky might look like from a planet in a particularly dusty solar system. Dust that orbits a star in the plane of the solar system is called zodiacal dust, and the light reflected and scattered by that dust is called zodiacal light. The Hunt for Observable Signatures of Terrestrial Systems, or HOSTS, survey was tasked with learning more about the effect of zodiacal dust on the search for new worlds, to help guide the design of future planet-hunting missions. Image Credits: NASA/JPL-Caltech.

Veils of dust wrapped around distant stars could make it difficult for scientists to find potentially habitable planets in those star systems. The Hunt for Observable Signatures of Terrestrial Systems, or HOSTS, survey was tasked with learning more about the effect of dust on the search for new worlds. The goal is to help guide the design of future planet-hunting missions. In a new paper published in the Astrophysical Journal, HOSTS scientists report on the survey’s initial findings.

Using the Large Binocular Telescope Interferometer, or LBTI, on Mount Graham in Arizona, the HOSTS survey determines the brightness of warm dust floating in the orbital planes of other stars (called exozodiacal dust). In particular, HOSTS has studied dust in nearby stars’ habitable zones, where liquid water could exist on the surface of a planet. The LBTI is five to 10 times more sensitive than the previous telescope capable of detecting exozodiacal dust, the Keck Interferometer Nuller.

Image above: The Large Binocular Telescope Interferometer, or LBTI, is a ground-based instrument connecting two 8-meter class telescopes on Mount Graham in Arizona to form the largest single-mount telescope in the world. The interferometer is designed to detect and study stars and planets outside our solar system. Image Credits: NASA/JPL-Caltech.

Among the findings detailed in the new paper, the HOSTS scientists report that a majority of Sun-like stars in their survey do not possess high levels of dust -- good news for future efforts to study potentially-habitable planets around those stars. A final report on the full HOSTS survey results is expected early next year.

More information about the new findings from HOSTS and the search for Earthlike planets beyond our solar system is available in this news release from the University of Arizona:

The LBTI is funded by NASA's Exoplanet Exploration Program office and managed by the agency's Jet Propulsion Laboratory in Pasadena, California. JPL is a division of Caltech, also in Pasadena. Six JPL scientists co-authored the new research paper. The LBTI is an international collaboration among institutions in the U.S., Italy and Germany, and it is managed and headquartered at the University of Arizona in Tucson.

NASA is taking a multifaceted approach to finding and studying planets outside our solar system. On April 18, NASA launched its newest planet-hunting observatory, the Transiting Exoplanet Survey Satellite (TESS), which is expected to find thousands of new exoplanets, mostly around stars smaller than our Sun.

Large Binocular Telescope Interferometer (LBTI):


Images (mentioned), Text, Credits: NASA/Tony Greicius/JPL/Calla Cofield/University of Arizona/Doug Carroll.


Gaia creates richest star map of our Galaxy – and beyond

ESA - Gaia Mission patch.

25 April 2018

ESA’s Gaia mission has produced the richest star catalogue to date, including high-precision measurements of nearly 1.7 billion stars and revealing previously unseen details of our home Galaxy.

Gaia’s sky in colour

A multitude of discoveries are on the horizon after this much awaited release, which is based on 22 months of charting the sky. The new data includes positions, distance indicators and motions of more than one billion stars, along with high-precision measurements of asteroids within our Solar System and stars beyond our own Milky Way Galaxy.

Preliminary analysis of this phenomenal data reveals fine details about the make-up of the Milky Way’s stellar population and about how stars move, essential information for investigating the formation and evolution of our home Galaxy.

“The observations collected by Gaia are redefining the foundations of astronomy,” says Günther Hasinger, ESA Director of Science.

“Gaia is an ambitious mission that relies on a huge human collaboration to make sense of a large volume of highly complex data. It demonstrates the need for long-term projects to guarantee progress in space science and technology and to implement even more daring scientific missions of the coming decades.”

Gaia was launched in December 2013 and started science operations the following year. The first data release, based on just over one year of observations, was published in 2016; it contained distances and motions of two million stars.

The new data release, which covers the period between 25 July 2014 and 23 May 2016, pins down the positions of nearly 1.7 billion stars, and with a much greater precision. For some of the brightest stars in the survey, the level of precision equates to Earth-bound observers being able to spot a Euro coin lying on the surface of the Moon.

With these accurate measurements it is possible to separate the parallax of stars – an apparent shift on the sky caused by Earth’s yearly orbit around the Sun – from their true movements through the Galaxy.

The Galactic census takes shape

The new catalogue lists the parallax and velocity across the sky, or proper motion, for more than 1.3 billion stars. From the most accurate parallax measurements, about ten per cent of the total, astronomers can directly estimate distances to individual stars.

“The second Gaia data release represents a huge leap forward with respect to ESA’s Hipparcos satellite, Gaia’s predecessor and the first space mission for astrometry, which surveyed some 118 000 stars almost thirty years ago,” says Anthony Brown of Leiden University, The Netherlands. 

Anthony is the chair of the Gaia Data Processing and Analysis Consortium Executive, overseeing the large collaboration of about 450 scientists and software engineers entrusted with the task of creating the Gaia catalogue from the satellite data.

Gaia’s first and second data releases

“The sheer number of stars alone, with their positions and motions, would make Gaia’s new catalogue already quite astonishing,” adds Anthony.

“But there is more: this unique scientific catalogue includes many other data types, with information about the properties of the stars and other celestial objects, making this release truly exceptional.” 

Something for everyone

The comprehensive dataset provides a wide range of topics for the astronomy community.

As well as positions, the data include brightness information of all surveyed stars and colour measurements of nearly all, plus information on how the brightness and colour of half a million variable stars change over time. It also contains the velocities along the line of sight of a subset of seven million stars, the surface temperatures of about a hundred million and the effect of interstellar dust on 87 million.

Asteroid survey

Gaia also observes objects in our Solar System: the second data release comprises the positions of more than 14 000 known asteroids, which allows precise determination of their orbits. A much larger asteroid sample will be compiled in Gaia’s future releases.

Further afield, Gaia closed in on the positions of half a million distant quasars, bright galaxies powered by the activity of the supermassive black holes at their cores. These sources are used to define a reference frame for the celestial coordinates of all objects in the Gaia catalogue, something that is routinely done in radio waves but now for the first time is also available at optical wavelengths.

Cosmic scales covered by Gaia

Major discoveries are expected to come once scientists start exploring Gaia’s new release. An initial examination performed by the data consortium to validate the quality of the catalogue has already unveiled some promising surprises – including new insights on the evolution of stars.

Galactic archaeology

The new Gaia data are so powerful that exciting results are just jumping at us,” says Antonella Vallenari from the Istituto Nazionale di Astrofisica (INAF) and the Astronomical Observatory of Padua, Italy, deputy chair of the data processing consortium executive board.

“For example, we have built the most detailed Hertzsprung-Russell diagram of stars ever made on the full sky and we can already spot some interesting trends. It feels like we are inaugurating a new era of Galactic archaeology.”

Gaia spacecraft

Named after the two astronomers who devised it in the early twentieth century, the Hertzsprung-Russell diagram compares the intrinsic brightness of stars with their colour and is a fundamental tool to study populations of stars and their evolution.

A new version of this diagram, based on four million stars within five thousand light-years from the Sun selected from the Gaia catalogue, reveals many fine details for the first time. This includes the signature of different types of white dwarfs – the dead remnants of stars like our Sun – such that a differentiation can be made between those with hydrogen-rich cores and those dominated by helium. 

Hertzsprung-Russell diagram

Combined with Gaia measurements of star velocities, the diagram enables astronomers to distinguish between various populations of stars of different ages that are located in different regions of the Milky Way, such as the disc and the halo, and that formed in different ways. Further scrutiny suggests that the fast-moving stars thought to belong to the halo encompass two stellar populations that originated via two different formation scenarios, calling for more detailed investigations.

“Gaia will greatly advance our understanding of the Universe on all cosmic scales,” says Timo Prusti, Gaia project scientist at ESA.

“Even in the neighbourhood of the Sun, which is the region we thought we understood best, Gaia is revealing new and exciting features.”

Galaxy in 3D

For a subset of stars within a few thousand light-years of the Sun, Gaia has measured the velocity in all three dimensions, revealing patterns in the motions of stars that are orbiting the Galaxy at similar speeds.

Future studies will confirm whether these patterns are linked to perturbations produced by the Galactic bar, a denser concentration of stars with an elongated shape at the centre of the Galaxy, by the spiral arm architecture of the Milky Way, or by the interaction with smaller galaxies that merged with it billions of years ago.

Rotation of the Large Magellanic Cloud

At Gaia’s precision, it is also possible to see the motions of stars within some globular clusters – ancient systems of stars bound together by gravity and found in the halo of the Milky Way – and within our neighbouring galaxies, the Small and Large Magellanic Clouds.

Gaia data were used to derive the orbits of 75 globular clusters and 12 dwarf galaxies that revolve around the Milky Way, providing all-important information to study the past evolution of our Galaxy and its environment, the gravitational forces that are at play, and the distribution of the elusive dark matter that permeates galaxies.

Globular cluster and dwarf galaxy orbits

“Gaia is astronomy at its finest,” says Fred Jansen, Gaia mission manager at ESA.

“Scientists will be busy with this data for many years, and we are ready to be surprised by the avalanche of discoveries that will unlock the secrets of our Galaxy.”

Star motions in the sky

Notes for Editors:

The data from Gaia’s first release can be accessed at

The content of the second Gaia release was presented today during a media briefing at the ILA Berlin Air and Space Show in Germany.

A series of scientific papers describing the data contained in the release and their validation process will appear in a special issue of Astronomy & Astrophysics.

A series of 360-degree videos and other Virtual Reality visualisation resources are available at

Gaia is an ESA mission to survey more than one billion stars in our Galaxy and its local neighbourhood in order to build the most precise 3D map of the Milky Way and answer questions about its structure, origin and evolution.

A large pan-European team of expert scientists and software developers, the Data Processing and Analysis Consortium, located in and funded by many ESA member states, is responsible for the processing and validation of Gaia’s data, with the final objective of producing the Gaia Catalogue. Scientific exploitation of the data will only take place once they are openly released to the community.

More data releases will be issued in future years, with the final Gaia catalogue to be published in the 2020s. This will be the definitive stellar catalogue for the foreseeable future, playing a central role in a wide range of fields in astronomy.

Gaia was originally planned for a five-year mission, operating until mid-2019. ESA has already approved an indicative extension until the end of 2020, which is up for confirmation at the end of this year.

Related article:

Gaia’s billion-star map hints at treasures to come (Gaia first data release)

ESA Gaia:

Images, Videos, Text, Credits: ESA/Markus Bauer/Timo Prusti/Fred Jansen/INAF, Astronomical Observatory of Padua/Antonella Vallenari/Leiden Observatory/Anthony Brown/ESA/Gaia/DPAC/CC BY-SA 3.0 IGO.

Best regards,

What Uranus Cloud Tops Have in Common With Rotten Eggs

GEMINI Observatory logo.

April 25, 2018

Image above: Arriving at Uranus in 1986, Voyager 2 observed a bluish orb with extremely subtle features. A haze layer hid most of the planet's cloud features from view. Image Credits: NASA/JPL-Caltech.

Even after decades of observations and a visit by NASA's Voyager 2 spacecraft, Uranus held on to one critical secret -- the composition of its clouds. Now, one of the key components of the planet's clouds has finally been verified.

A global research team that includes Glenn Orton of NASA's Jet Propulsion Laboratory in Pasadena, California, has spectroscopically dissected the infrared light from Uranus captured by the 26.25-foot (8-meter) Gemini North telescope on Hawaii's Mauna Kea. They found hydrogen sulfide, the odiferous gas that most people avoid, in Uranus' cloud tops. The long-sought evidence was published in the April 23rd issue of the journal Nature Astronomy.

The detection of hydrogen sulfide high in Uranus' cloud deck (and presumably Neptune's) is a striking difference from the gas giant planets located closer to the Sun -- Jupiter and Saturn -- where ammonia is observed above the clouds, but no hydrogen sulfide. These differences in atmospheric composition shed light on questions about the planets' formation and history.

Gemini North telescope on Hawaii's Mauna Kea. Image Credits: CNRC-NRC

"We've strongly suspected that hydrogen sulfide gas was influencing the millimeter and radio spectrum of Uranus for some time, but we were unable to attribute the absorption needed to identify it positively. Now, that part of the puzzle is falling into place as well," Orton said.

The Gemini data, obtained with the Near-Infrared Integral Field Spectrometer (NIFS), sampled reflected sunlight from a region immediately above the main visible cloud layer in Uranus' atmosphere.

"While the lines we were trying to detect were just barely there, we were able to detect them unambiguously thanks to the sensitivity of NIFS on Gemini, combined with the exquisite conditions on Mauna Kea," said lead author Patrick Irwin of the University of Oxford, U.K.

No worries, though, that the odor of hydrogen sulfide would overtake human senses. According to Irwin, "Suffocation and exposure in the negative 200 degrees Celsius [392 degrees Fahrenheit] atmosphere made of mostly hydrogen, helium and methane would take its toll long before the smell."

Read more on the news of Uranus' atmosphere from Gemini Observatory here:

Caltech in Pasadena, California, manages JPL for NASA.

Images (mentioned), Text, Credits: NASA/JoAnna Wendel/JPL/Gretchen McCartney/Gemini Observatory/Peter Michaud.