samedi 6 août 2016

NASA Sees Tropical Storm Earl Over Mexico












NASA - NOAA Suomi NPP satellite logo.

Aug. 6, 2016

Earl (Caribbean Sea)

Tropical Storm Earl made landfall as a Category 1 hurricane in Belize on Aug. 4, and NASA-NOAA's Suomi NPP satellite saw the storm move over Mexico's Yucatan Peninsula the next day.


Image above: This true color image from NASA-NOAA Suomi NPP satellite on Aug. 4 at 3:30 p.m. EDT (19:30 UTC) shows Tropical Storm Earl over Mexico's Yucatan Peninsula. Image Credits: NOAA/NASA.

On Aug. 4 at 3:30 p.m. EDT (19:30 UTC) the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA's Suomi NPP satellite captured a visible-light image of Earl over the Yucatan. The VIIRS image showed that Earl still had thunderstorms around its center of circulation, but bands of thunderstorms around the center were fragmented.

On Aug. 5 a tropical storm warning is in effect for Ciudad del Carmen westward to Laguna Verde, Mexico, as Earl was hugging the coast of the Bay of Campeche.

At 8 a.m. EDT (1200 UTC) the center of Tropical Storm Earl was estimated near 18.5 north latitude and 93.5 west longitude. That put Earl's center just 65 miles (105 km) east-northeast of Coatzacoalcos, Mexico.

Suomi NPP satellite. Image Credits: NASA/NOAA

Earl is moving toward the west-northwest at near 12 mph (19 kph). The National Hurricane Center forecasts a turn toward the west and a decrease in forward speed later today (Aug. 5). On the forecast track, the center of Earl will be moving near the coast along the extreme southern Bay of Campeche today and tonight. Earl will then move into southeastern mainland Mexico on Saturday, Aug. 6.

Maximum sustained winds remain near 40 mph (65 kph) with higher gusts. Little change in strength is likely today or tonight, with weakening expected on Saturday when Earl moves into mainland Mexico.

For updated forecasts from NHC, visit: http://www.nhc.noaa.gov

For more information about NASA-NOAA's Suomi NPP satellite, visit: http://www.nasa.gov/mission_pages/NPP/main/

Images (mentioned), Text, Credits: NASA's Goddard Space Flight Center, by Rob Gutro.

Greetings, Orbiter.ch

vendredi 5 août 2016

CERN - Chicago sees floods of LHC data and new results at ICHEP












CERN - European Organization for Nuclear Research logo.

August 5, 2016


Image above: One of the many meetings at CERN where physicists prepared to showcase results at ICHEP. (Image: Maximilien Brice/ CERN).

Particle physicists are showcasing a wealth of brand new results from the Large Hadron Collider (LHC) experiments at CERN [1] at the “ICHEP 2016” [2] conference in Chicago. With a flood of new data, the experiment collaborations can now dive in and explore at the new energy frontier of 13 TeV, following last year’s first glimpse of physics at this unprecedented energy level. LHC collaborations are presenting more than 100 different new results, including many analyses based on newly taken 2016 data.

Thanks to the outstanding performances of the LHC, experiments have already recorded about 5 times more data in 2016 than in 2015, in just a few months of operations. The LHC surpassed its design luminosity in June – a parameter measuring the number of collisions per second. The peak luminosity reaches about 1 billion collisions per second so that even the rarest processes at the highest effective energy could occur. The LHC is thus running beyond expectations and the objective of 25 inverse femtobarn [3] of proton–proton collisions delivered to experiments for the whole of 2016 is within sight. The Worldwide LHC Computing Grid has stretched well beyond previous records, with more than 25 PB of data stored and processed since the beginning of the year.

“The LHC really entered a new regime by reaching its nominal luminosity, now exceeded by 20%,” said CERN Director for Accelerators and Technology, Frédérick Bordry. “It’s a major achievement and we can be confident that we will go beyond our goals for the full second run of the LHC.”


Images above: Event selected in the search for a CP-odd Higgs boson decaying to Zh (ATLAS-CONF-2016-015). The resolved jets are represented by red and yellow cones. The Z boson is reconstructed as Z → e+e-, and the electron tracks are shown as green lines. The di-jet system has an invariant mass of 128 GeV, and the measured mZh in this event is 268 GeV. (Image: ATLAS Collaboration/CERN).

Physicists have been hard at work in the past months dealing with the huge amount of data recorded by the LHC experiments. With a larger data set now analysed, more precise measurements of the Standard Model processes and more sensitive searches for the direct production of new particles at the highest energy are possible. As an example, the 125 GeV Higgs boson, discovered in 2012, has now also been observed at the new energy of 13 TeV with higher statistical significance. In addition, both ATLAS and CMS experiments have made new precise measurements of Standard Model processes, especially looking for anomalous particle interactions at high mass, a very sensitive but indirect test for physics beyond the Standard Model.

“This is one of the most exciting times in recent years for physicists, as we dig into the unknown in earnest: the particle physics at an energy never explored before,” said CERN Director for Research and Computing, Eckhard Elsen.

ATLAS and CMS have also looked for any signs of the direct production of new particles predicted by Supersymmetry and other exotic theories of physics beyond the Standard Model, but no compelling evidence of new physics has appeared yet. In particular, the intriguing hint of a possible resonance at 750 GeV decaying into photon pairs, which caused considerable interest from the 2015 data, has not reappeared in the much larger 2016 data set and thus appears to be a statistical fluctuation.


Image above: This image shows a collision event with the largest-mass jet pair fulfilling all analysis requirements observed so far by the CMS detector in proton-proton collision data collected in 2016. The mass of the di-jet system is 7.7 TeV. Both jets are reconstructed in the barrel region and each have transverse momenta of over 3 TeV. (Image: Thomas Mc Cauley/CERN).

LHCb are presenting many interesting new results as well, in the domain of flavour physics. A particular highlight is the discovery of the decay mode B0->K+K-, the rarest B-meson decay into a hadronic final state ever observed, as well as studies of unprecedented sensitivity of CP violation, a very subtle phenomenon explaining nature’s “preference” for matter over antimatter. LHCb have also conducted measurements that could help to reveal some new phenomena such as the first measurement of the photon polarisation in radiative decays of Bs mesons and determinations of the production cross-sections of several key processes at a collision energy of 13 TeV – some of which, at first sight, are at variance with current predictions.

All four experiments are presenting results from heavy ion collisions at the LHC. Amongst these, The ALICE Collaboration are presenting new measurements of the properties of quark-gluon plasma – a state of matter that existed a few millionths of a second after the Big Bang. ALICE physicists are studying how the nuclear forces are modified in this primordial state of matter. Researchers also measured the viscosity of the plasma at the new energy, showing that it flows almost like an ideal liquid, the same behaviour this is observed at lower collision energies.

“We're just at the beginning of the journey,” said CERN Director-General, Fabiola Gianotti. “The superb performance of the LHC accelerator, experiments and computing bode extremely well for a detailed and comprehensive exploration of the several TeV energy scale, and significant progress in our understanding of fundamental physics.”

video
ICHEP 2016 - Interview: Fabiola Gianotti, CERN Director-General

Video above: CERN Director-General, Fabiola Gianotti, shares her thoughts on the LHC physics results presented at ICHEP 2016. (Video: Jacques Herve Fichet, Photography: Maximilien Brice/CERN).

video
ICHEP 2016 - Interview: Gian Giudice, CERN Head of Theory

Video above: CERN Head of Theory Department, Gian Giudice, shares his thoughts on the LHC physics results presented at ICHEP 2016. (Video: BBC Horizon / Edited by CERN).

Updates from the experiments:

ALICE: http://aliceinfo.cern.ch/Public/Welcome.html

ATLAS: https://atlas.cern/tags/ichep2016

CMS: http://cms-results.web.cern.ch/cms-results/public-results/preliminary-results/ICHEP-2016.html

LHCb: http://lhcb-public.web.cern.ch/lhcb-public/Welcome.html

Notes:

[1] CERN, the European Organization for Nuclear Research, is the world's leading laboratory for particle physics. Its headquarters are in Geneva. Its Member States are: Austria, Belgium, Bulgaria, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Israel, Italy, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Spain, Sweden, Switzerland and United Kingdom. Cyprus and Serbia are Associate Member States in the pre-stage to Membership. Pakistan and Turkey are Associate Member States. The European Union, India, Japan, JINR, the Russian Federation, UNESCO and the United States of America have Observer status.

[2] The 38th International Conference on High Energy Physics, 3–10 August in Chicago, USA http://www.ichep2016.org/ .

[3] One inverse femtobarn at the LHC corresponds to approximately 100 trillion (100x1012) proton–proton collisions.

Related links:

Large Hadron Collider (LHC): http://home.cern/topics/large-hadron-collider

Worldwide LHC Computing Grid: http://home.cern/about/computing/worldwide-lhc-computing-grid

Standard Model: http://home.cern/tags/standard-model

Higgs boson: http://home.cern/topics/higgs-boson

Supersymmetry: http://home.cern/about/physics/supersymmetry

Big Bang: http://home.cern/tags/big-bang

For more information about the European Organization for Nuclear Research (CERN), visit: http://home.web.cern.ch/

Images (mentioned), Videos (mentioned), Text, Credits: CERN/Kathryn Coldham.

Best regards, Orbiter.ch

IRIS Spots Plasma Rain on Sun's Surface










NASA - Interface Region Imaging Spectrograph (IRIS) logo.

Aug. 5, 2016

IRIS Spots Plasma Rain on Sun's Surface

Image Credits: NASA's Goddard Space Flight Center; Joy Ng, producer/IRIS/Lockheed Martin Solar and Astrophysics Laboratory.

On July 24, 2016, NASA’s Interface Region Imaging Spectrograph, or IRIS, captured a mid-level solar flare: a sudden flash of bright light on the solar limb – the horizon of the sun – as seen at the beginning of this video. Solar flares are powerful explosions of radiation. During flares, a large amount of magnetic energy is released, heating the sun’s atmosphere and releasing energized particles out into space. Observing flares such as this helps the IRIS mission study how solar material and energy move throughout the sun’s lower atmosphere, so we can better understand what drives the constant changes we can see on our sun.

video
IRIS Spots Plasma Rain on Sun's Surface

Video Credits: NASA's Goddard Space Flight Center; Joy Ng, producer/IRIS/Lockheed Martin Solar and Astrophysics Laboratory.

As the video continues, solar material cascades down to the solar surface in great loops, a flare-driven event called post-flare loops or coronal rain. This material is plasma, a gas in which positively and negatively charged particles have separated, forming a superhot mix that follows paths guided by complex magnetic forces in the sun's atmosphere. As the plasma falls down, it rapidly cools – from millions down to a few tens of thousands of kelvins. The corona is much hotter than the sun’s surface; the details of how this happens is a mystery that scientists continue to puzzle out. Bright pixels that appear at the end of the video aren’t caused by the solar flare, but occur when high-energy particles bombard IRIS’s charge-coupled device camera – an instrument used to detect photons.

Related Links:

IRIS mission overview: https://www.nasa.gov/mission_pages/iris/overview/index.html

IRIS (Interface Region Imaging Spectrograph): http://www.nasa.gov/mission_pages/iris/index.html

Image (mentioned), Video (mentioned), Text, Credits: NASA's Goddard Space Flight Center, by Lina Tran/Rob Garner.

Greetings, Orbiter.ch

Decades of Discovery: NASA’s Exploration of Jupiter












NASA - JUNO Mission logo.

Aug. 5, 2016


Image above: This illustration depicts NASA's Juno spacecraft in orbit above Jupiter. From its unique polar orbit, Juno will repeatedly dive between the planet and its intense belts of charged particle radiation, coming only about 3,000 miles (5,000 kilometers) from the cloud tops at closest approach. Image Credits: NASA/JPL-Caltech.

Launched five years ago on Aug. 5, 2011, NASA’s Juno mission maneuvered into orbit around Jupiter on July 4, 2016, joining a long tradition of discovery at the gas giant.

One of the brightest objects in the night sky, Jupiter has enthralled humans since ancient times. Today, scientists believe that learning more about the planet may be the key to discovering our solar system’s origins and formation. They theorize that Jupiter didn’t always rest where it is now, but that it moved throughout the solar system in its youth, disrupting the formation of Mars, influencing the formation and location of the asteroid belt, and more.

Scientists began to use space missions to unlock the planet’s secrets in the early 1970s when Juno’s earliest ancestors, Pioneer 10 and 11, launched. The pair of spacecraft reached the planet in late 1973 and early 1974. For the first time ever, scientists could obtain direct observations and close-up images of Jupiter, its moons and the mysterious Great Red Spot.


Image above: An artist's concept of the Pioneer 10 spacecraft. Image Credit: NASA.

From Pioneer’s findings, scientists were able to make numerous conclusions about Jupiter. They found that the planet is composed mostly of liquid, and that it has a magnetotail, an extension of its magnetic field, like Earth. This hinted at Jupiter’s composition and the possibility of a solid core. They also got a close look at Jupiter’s clouds – from 26,000 miles (about 42,000 km) – to determine weather patterns.

The Pioneer missions paved the way for a second set of Jupiter-focused missions in the late 1970s, Voyager 1 and 2. Launched in 1977, the spacecraft are most famous for traversing to the outermost portion of the solar system – Voyager 1 has even passed its outer limits and has now passed into the space between solar systems. In time, Voyager 2 and the Pioneer missions will also leave the solar system. The Voyager pair flew past Jupiter in 1979, taking more than 52,000 photos of the planet and its moons over the course of several months.

These images and accompanying observations sparked seemingly countless new discoveries. The data revealed many features of the weather on Jupiter, including the existence of lightning in the cloud tops and of hurricane-like storm systems. Plus, for the first time, scientists discovered the existence of active volcanoes elsewhere than Earth, on the planet’s moon Io.


Image above: Voyager 1 took this photo of Jupiter and two of its satellites (Io, left, and Europa) on Feb. 13, 1979. This photo was assembled from three black and white negatives by the Image Processing Lab at Jet Propulsion Laboratory. Image Credits: NASA/JPL.

The Galileo missions to Jupiter followed in the late 1980s. Unlike previous missions, this set of spacecraft – an atmospheric probe and an orbiter – were designed to orbit the planet rather than collect data on flyby. The probe was the first spacecraft to directly measure characteristics of Jupiter’s atmosphere – descending 95 miles (153 kilometers) into it before melting and vaporizing from the extreme heat. The probe passed 58 minutes of atmospheric data to the orbiter, which then transmitted it back to Earth. The data included measurements of Jupiter’s atmospheric elements and showed that their abundance differed from that of the sun, providing insight into the planet’s formation.

The orbiter itself made numerous long-term observations about the Jupiter system, including finding evidence to support the theory that an ocean of water lies under the surface of the moon Europa and finding Jupiter’s ring system, a nearly invisible set of rings composed of dust created by meteoroid impacts with the planet’s four moons. In July 1994, Galileo also witnessed the collision of Comet Shoemaker-Levy 9 with Jupiter, the first observation of such an impact as it occurred on any planet besides Earth.

The Ulysses mission to study the sun collected data on Jupiter’s magnetosphere while the planet provided a gravitational assist to change the spacecraft’s trajectory in 1992. The Cassini spacecraft also observed Jupiter in 2000 on its way to its target destination, Saturn. Cassini’s camera took 26,000 images of the planet and its moons and created the most detailed global color portrait of Jupiter ever produced at the time.


Image above: This is a composite photo, assembled from separate images of Jupiter and comet Shoemaker-Levy 9, as imaged by the NASA/ESA Hubble Space Telescope in 1994. Image Credits: NASA, ESA, H. Weaver and E. Smith (STScI) and J. Trauger and R. Evans (NASA's Jet Propulsion Laboratory).

More recently, New Horizons, a mission to Pluto, added to these observations during its flyby of Jupiter in 2007, finding the planet changed since previous looks by NASA – the Galileo spacecraft burned up in Jupiter’s atmosphere in fall 2003. New Horizons spent about six months observing the Jupiter planet system during its flyby on the way to Pluto, further exploring its weather systems, moons and rings. Perhaps most notably, New Horizons saw about 36 volcanoes on Io and measured the temperature of lava, finding it similar to that of Earth-based volcanoes.

The Hubble Space Telescope has made multiple observations and taken numerous photos of Jupiter since its launch in April 1990. Hubble’s observations of the planet stretch over 26 years, and many of its observations are concurrent with other Jupiter missions, particularly Galileo. In fact, Hubble also witnessed the collision of Comet Shoemaker-Levy 9 with Jupiter, providing another perspective of the impact sites. Hubble’s observations of the gas giant have continued to the present day. In October 2015, Hubble photos showed changes in Jupiter’s Great Red Spot, and in June 2016, Hubble took awe-inspiring photos of auroras on the planet’s poles. Hubble’s observations of the solar system and the wider universe are expected to continue through 2020 and beyond.

With Juno’s successful orbit insertion at Jupiter in July 2016, scientists expect to release information about the mission’s first findings in September. NASA has already released several images taken of the planet by the JunoCam camera. Juno will make observations about Jupiter’s atmosphere and magnetic and gravitational fields, providing more information about the planet’s structure so scientists can deepen their understanding of Jupiter’s origin and evolution. Any of these clues could begin to unravel the mystery of the solar system’s origins and formation.

Related information:

    http://www.nasa.gov/mission_pages/juno/main/index.html
    http://www.nasa.gov/centers/ames/missions/archive/pioneer10-11.html
    http://www.nasa.gov/mission_pages/voyager/index.html
    https://solarsystem.nasa.gov/galileo/index.cfm
    http://pluto.jhuapl.edu/Mission/The-Path-to-Pluto/Jupiter-Encounter.php
    https://www.nasa.gov/mission_pages/hubble/main/index.html
    http://www.nasa.gov/mission_pages/newhorizons/main/index.html
    https://www.nasa.gov/pioneer/
    https://www.nasa.gov/mission_pages/voyager/index.html

Images (mentioned), Text, Credits: NASA's Goddard Space Flight Center, by Ashley Morrow.

Greetings, Orbiter.ch

A Hubble Sky Full of Stars












NASA - Hubble Space Telescope patch.

Aug. 5, 2016


Located approximately 22,000 light-years away in the constellation of Musca (The Fly), this tightly packed collection of stars — known as a globular cluster — goes by the name of NGC 4833. This NASA/ESA Hubble Space Telescope image shows the dazzling stellar group in all its glory.

NGC 4833 is one of the over 150 globular clusters known to reside within the Milky Way. These objects are thought to contain some of the oldest stars in our galaxy. Studying these ancient cosmic clusters can help astronomers to unravel how a galaxy formed and evolved, and give an idea of the galaxy’s age.

Globular clusters are responsible for some of the most striking sights in the cosmos, with hundreds of thousands of stars congregating in the same region of space. Hubble has observed many of these clusters during its time in orbit around our planet, each as breathtaking as the last.

video
Hubble and the sunrise over Earth

For more information about the Hubble Space Telescope, visit:

http://hubblesite.org/
http://www.nasa.gov/hubble
https://www.spacetelescope.org/

Image credits: ESA/Hubble and NASA/Video credit: European Space Agency (ESA)/Text credits: European Space Agency/NASA/Ashley Morrow.

Best regards, Orbiter.ch

jeudi 4 août 2016

SDO Status Update - Aug. 4, 2016












NASA - Solar Dynamics Observatory (SDO) patch.

Aug. 4, 2016

UPDATE, Aug. 4, 2016 (3:26 p.m. EDT) - Two of SDO’s three science instruments – the Helioseismic and Magnetic Imager, or HMI, and the Extreme Ultraviolet Variability Experiment, or EVE – are online and sending science data to Earth. The SDO team is currently working on getting its third science instrument – the Atmospheric Imaging Assembly, or AIA – back online.

Original Story, Aug. 3, 2016 (5:03 p.m. EDT) - NASA’s Solar Dynamics Observatory, or SDO, saw a lunar transit – when the moon passes between the spacecraft and the sun – on Aug. 2, 2016, from 7:13 a.m. to 8:08 a.m. EDT. The spacecraft did not go back into science mode at the end of the transit. SDO is currently in inertial mode. The team is receiving data from the spacecraft and is bringing SDO’s instruments back online.


Image above: NASA’s Solar Dynamics Observatory, or SDO, saw a lunar transit – when the moon passes between the spacecraft and the sun – on Aug. 2, 2016, from 7:13 a.m. to 8:08 a.m. EDT. Image Credits: NASA/SDO.

Related links:

Eclipses and Transits: http://www.nasa.gov/topics/solarsystem/features/eclipse/index.html

Solar Dynamics Observatory (SDO): http://www.nasa.gov/mission_pages/sdo/main/index.html

Image (mentioned), Text, Credits: NASA's Goddard Space Flight Center/Sarah Frazier/Rob Garner.

Greetings, Orbiter.ch

Expedition 48 Commander Jeff Williams Marks 500 Days in Space











ISS - Expedition 48 Mission patch.

Aug. 4, 2016


Image above: Commander Jeff Williams monitors bowling ball-sized internal satellites known as SPHERES during a maintenance run in the Japanese Kibo Laboratory Module.

Expedition 48 Commander Jeff Williams has accumulated 500 days of living in space over four missions as of today. Williams, who is scheduled to return to Earth Sept. 6, will break NASA astronaut Scott Kelly’s record of 520 days on Aug. 24.

While Williams marked his milestone, he spent most of the day researching fluid shifts from the lower body to the upper body caused by microgravity. The fluid shifts increase pressure on the head and eyes potentially affecting an astronaut’s vision. Cosmonauts OIeg Skripochka and Alexey Ovchinin assisted Williams during experiment operations.

Flight Engineer Kate Rubins continued her preparations for an Aug. 19 spacewalk with Williams to install a new International Docking Adapter. She worked in the Quest airlock today gathering tools and equipment the duo will use during their 6.5-hour spacewalk. She also spent some time with Japanese astronaut Takuya Onishi transferring cargo from the SpaceX Dragon cargo craft.

Get weekly video highlights at: http://jscfeatures.jsc.nasa.gov/videoupdate/

Related links:

International Docking Adapter: http://www.nasa.gov/feature/spacex-crs-9-carrying-crucial-port-to-station

SPHERES: http://www.nasa.gov/mission_pages/station/research/experiments/311.html

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

Expedition 48: https://www.nasa.gov/mission_pages/station/expeditions/expedition48/index.html

Image, Text, Credits: NASA/Mark Garcia.

Best regards, Orbiter.ch

NASA Rover Game Released for Curiosity’s Anniversary










NASA - Mars Science Laboratory (MSL) logo.

Aug. 4, 2016


Image above: NASA's Curiosity Mars rover began close-up investigation of a target called "Marimba," on lower Mount Sharp, during the week preceding the fourth anniversary of the mission's Aug. 6, 2016, landing. Curiosity's Navigation Camera took this shot of the rover's arm over Marimba on Aug. 2, 2016. Image Credits: NASA/JPL-Caltech/MSSS.

As Curiosity marks its fourth anniversary (in Earth years) since landing on Mars, the rover is working on collecting its 17th sample. While Curiosity explores Mars, gamers can join the fun via a new social media game, Mars Rover.

On their mobile devices, players drive a rover through rough Martian terrain, challenging themselves to navigate and balance the rover while earning points along the way. The game also illustrates how NASA's next Mars rover, in development for launch in 2020, will use radar to search for underground water.

"We're excited about a new way for people on the go to engage with Curiosity's current adventures on Mars and future exploration by NASA's Mars 2020 rover too," said Michelle Viotti, manager of Mars public engagement initiatives at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Using social networks, the user can share the fun with friends. The interest that is shared through gameplay also helps us open a door to deeper literacy in science, technology, engineering and mathematics." JPL collaborated with GAMEE, a network for game-players, for development of the game, called Mars Rover.

For more information about how the Mars Rover game relates to exploration by NASA's Mars rovers, visit: http://mars.nasa.gov/gamee-rover

Meanwhile, on Mars the real rover has driven to position for drilling into a rock target called "Marimba," to acquire rock powder for onboard laboratory analysis. The rover has begun a multi-month ascent of a mudstone geological unit as it heads toward higher and progressively younger geological evidence on Mount Sharp, including some rock types not yet explored.


Image above: This is a shareable image about a social media game called Mars Rover. On their mobile devices, players drive a rover through rough Martian terrain, challenging themselves to navigate and balance the rover while earning points along the way. Image Credits: NASA/JPL-Caltech/GAMEE.

The mission is examining the lower slopes of Mount Sharp, a layered mountain inside Gale Crater, to learn more about how and when ancient environmental conditions in the area evolved from freshwater settings into conditions drier and less favorable for life. Six of the mission's 13 drilled rock-samples so far, and two of its four scooped soil samples, have been collected since the third anniversary of landing. In its four years, Curiosity has returned more than 128,000 images and fired its laser more than 362,000 times. As of the fourth anniversary, Curiosity has driven 8.43 miles (13.57 kilometers).

Curiosity landed inside Mars' Gale Crater on Aug. 6, 2012, EDT (evening of Aug. 5, PDT), with a touchdown technique called the sky-crane maneuver. During the rover's first Earth year on Mars, the mission accomplished its main goal when it found and examined an ancient habitable environment. Researchers determined that a freshwater lake at the "Yellowknife Bay" site billions of years ago offered the chemical ingredients and energy favorable for supporting microbial life, if life has ever existed on Mars.

NASA's orbiters and rovers at Mars enable continued scientific discoveries and prepare the way for future astronauts to explore the Red Planet.

More information about NASA's Journey to Mars is available online at:

https://www.nasa.gov/topics/journeytomars

For more information about Curiosity, visit:

http://www.nasa.gov/msl

http://mars.nasa.gov/msl

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

Greetings, Orbiter.ch

ESA, NASA’s SOHO Sees Bright Sungrazer Comet












ESA & NASA - SOHO Mission patch.

Aug. 4, 2016


ESA and NASA’s Solar and Heliospheric Observatory, or SOHO, saw a bright comet plunge toward the sun on Aug. 3-4, 2016, at nearly 1.3 million miles per hour. Comets are chunks of ice and dust that orbit the sun, usually on highly elliptical orbits that carry them far beyond the orbit of Pluto at their farthest points. This comet, first spotted by SOHO on Aug. 1, is part of the Kreutz family of comets, a group of comets with related orbits that broke off of a huge comet several centuries ago.

This comet didn’t fall into the sun, but rather whipped around it – or at least, it would have if it had survived its journey. Like most sungrazing comets, this comet was torn apart and vaporized by the intense forces near the sun.

The disk of the sun is represented by the white circle in this image.

For more information about Solar and Heliospheric Observatory (SOHO), visit: http://www.nasa.gov/mission_pages/soho/index.html and http://sci.esa.int/soho/

Text by Sarah Frazier, NASA's Goddard Space Flight Center, Greenbelt, Md. Image credits: ESA/NASA/SOHO/Joy Ng.

Greetings, Orbiter.ch

mercredi 3 août 2016

First Map Of Thawed Areas Under Greenland Ice Sheet














NASA - EOS Aqua Mission logo / NASA - EOS Terra Mission logo.

Aug. 3, 2016

NASA researchers have helped produce the first map showing what parts of the bottom of the massive Greenland Ice Sheet are thawed – key information in better predicting how the ice sheet will react to a warming climate.

Greenland’s thick ice sheet insulates the bedrock below from the cold temperatures at the surface, so the bottom of the ice is often tens of degrees warmer than at the top, because the ice bottom is slowly warmed by heat coming from the Earth’s depths. Knowing whether Greenland’s ice lies on wet, slippery ground or is anchored to dry, frozen bedrock is essential for predicting how this ice will flow in the future, But scientists have very few direct observations of the thermal conditions beneath the ice sheet, obtained through fewer than two dozen boreholes that have reached the bottom. Now, a new study synthesizes several methods to infer the Greenland Ice Sheet’s basal thermal state –whether the bottom of the ice is melted or not– leading to the first map that identifies frozen and thawed areas across the whole ice sheet.

(Click on the image for enlarge)

Image above: This first-of-a-kind map, showing which parts of the bottom of the Greenland Ice Sheet are likely thawed (red), frozen (blue) or still uncertain (gray), will help scientists better predict how the ice will flow in a warming climate. Image Credits: NASA Earth Observatory/Jesse Allen.

“We’re ultimately interested in understanding how the ice sheet flows and how it will behave in the future,” said Joe MacGregor, lead author of the study and a glaciologist at NASA’s Goddard Space Flight Center in Greenbelt, Md. “If the ice at its bottom is at the melting point temperature, or thawed, then there could be enough liquid water there for the ice to flow faster and affect how quickly it responds to climate change.”

Artist's view of Aqua satellite. Image Credit: NASA

For this study, published last month in the Journal of Geophysical Research – Earth Surface, MacGregor’s team combined four different approaches to investigate the basal thermal state. First, they examined results from eight recent computer models of the ice sheet, which predict bottom temperatures.  Second, they studied the layers that compose the ice sheet itself, which are detected by radars onboard NASA’s Operation IceBridge aircraft and suggest where the bottom of the ice is melting rapidly. Third, they looked at where the ice surface speed measured by satellites exceeds its “speed limit”, the maximum velocity at which the ice could flow and still be frozen to the rock beneath it. Fourth, they studied imagery from the Moderate Resolution Imaging Spectroradiometers on the NASA Terra and Aqua satellites looking for rugged surface terrain that is usually indicative of ice sliding over a thawed bed.

Artist's concept of Terra satellite. Image Credit: NASA

“Each of these methods has strengths and weaknesses. Considering just one isn’t enough. By combining them, we produced the first large-scale assessment of Greenland’s basal thermal state,” MacGregor said.

For each method, MacGregor’s team looked for areas where the technique confidently inferred that the bed of Greenland’s ice sheet was thawed or frozen. They then looked at the places where these methods agreed and classified these areas as likely thawed or likely frozen. The zones where there was insufficient data or the methods disagreed, they classified as uncertain.

From this synthesis, MacGregor and his colleagues determined that the bed is likely thawed under Greenland’s southwestern and northeastern ice drainages, while it’s frozen in the interior and west of the ice sheet’s central ice divide. For a third of the Greenland ice sheet, there’s not enough data available to determine its basal thermal state.

MacGregor said the team’s map is just one step in fully assessing the thermal state of the bottom of Greenland’s ice sheet.

“I call this the piñata, because it’s a first assessment that is bound to get beat up by other groups as techniques improve or new data are introduced. But that still makes our effort essential, because prior to our study, we had little to pick on,” MacGregor said.

Related links:

Aqua Satellite: http://www.nasa.gov/mission_pages/aqua/index.html

Terra Satellite: http://www.nasa.gov/mission_pages/terra/index.html

IceBridge: http://www.nasa.gov/mission_pages/icebridge/index.html

Goddard Space Flight Center: https://www.nasa.gov/centers/goddard/home/index.html

Jet Propulsion Laboratory (JPL): https://www.nasa.gov/centers/jpl/home/index.html

Images (mentioned), Text, Credits: NASA's Earth Science News Team, by Maria-José Viñas/Karl Hille.

Greetings, Orbiter.ch

What’s Inside Ceres? New Findings from Gravity Data












NASA - Dawn Mission patch.

Aug. 3, 2016

In the tens of thousands of photos returned by NASA’s Dawn spacecraft, the interior of Ceres isn’t visible. But scientists have powerful data to study Ceres’ inner structure: Dawn’s own motion.

Since gravity dominates Dawn's orbit at Ceres, scientists can measure variations in Ceres’ gravity by tracking subtle changes in the motion of the spacecraft. Using data from Dawn, scientists have mapped the variations in Ceres' gravity for the first time in a new study in the journal Nature, which provides clues to the dwarf planet's internal structure.

"The new data suggest that Ceres has a weak interior, and that water and other light materials partially separated from rock during a heating phase early in its history," said Ryan Park, the study’s lead author and the supervisor of the solar system dynamics group at NASA’s Jet Propulsion Laboratory, Pasadena, California.

Ceres' gravity field is measured by monitoring radio signals sent to Dawn, and then received back on Earth, by NASA’s Deep Space Network. This network is a collection of large antennas at three locations around the globe that communicate with interplanetary spacecraft. Using these signals, scientists can measure the spacecraft's speed to a precision of 0.004 inches (0.1 millimeters) per second, and then calculate the details of the gravity field.

Ceres has a special property called "hydrostatic equilibrium," which was confirmed in this study. This means that Ceres' interior is weak enough that its shape is governed by how it rotates. Scientists reached this conclusion by comparing Ceres' gravity field to its shape. Ceres' hydrostatic equilibrium is one reason why astronomers classified the body as a dwarf planet in 2006.


Image above: This artist's concept shows a diagram of how the inside of Ceres could be structured, based on data about the dwarf planet's gravity field from NASA's Dawn mission. Image Credits: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.

The data indicate that Ceres is “differentiated,” which means that it has compositionally distinct layers at different depths, with the densest layer at the core. Scientists also have found that, as they suspected, Ceres is much less dense than Earth, the moon, giant asteroid Vesta (Dawn’s previous target) and other rocky bodies in our solar system. Additionally, Ceres has long been suspected to contain low-density materials such as water ice, which the study shows separated from the rocky material and rose to the outer layer along with other light materials.

"We have found that the divisions between different layers are less pronounced inside Ceres than the moon and other planets in our solar system," Park said. “Earth, with its metallic core, semi-fluid mantle and outer crust, has a more clearly defined structure than Ceres," Park said.

Scientists also found that high-elevation areas on Ceres displace mass in the interior. This is analogous to how a boat floats on water: the amount of displaced water depends on the mass of the boat. Similarly, scientists conclude that Ceres’ weak mantle can be pushed aside by the mass of mountains and other high topography in the outermost layer as though the high-elevation areas "float" on the material below. This phenomenon has been observed on other planets, including Earth, but this study is the first to confirm it at Ceres.

The internal density structure, based on the new gravity data, teaches scientists about what internal processes could have occurred during the early history of Ceres. By combining this new information with previous data from Dawn about Ceres' surface composition, they can reconstruct that history: Water must have been mobile in the ancient subsurface, but the interior did not heat up to the temperatures at which silicates melt and a metallic core forms.

Artist's view of Dawn passing over Ceres. Image Credits: NASA/JPL

"We know from previous Dawn studies that there must have been interactions between water and rock inside Ceres," said Carol Raymond, a co-author and Dawn’s deputy principal investigator based at JPL. "That, combined with the new density structure, tells us that Ceres experienced a complex thermal history."

Dawn's mission is managed by JPL for NASA's Science Mission Directorate in Washington D.C. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Alabama. UCLA is responsible for overall Dawn mission science. Orbital ATK Inc., in Dulles, Virginia, designed and built the spacecraft. The German Aerospace Center, Max Planck Institute for Solar System Research, Italian Space Agency and Italian National Astrophysical Institute are international partners on the mission team. For a complete list of mission participants, visit: http://dawn.jpl.nasa.gov/mission

More information about Dawn is available at the following sites:

http://dawn.jpl.nasa.gov

http://www.nasa.gov/dawn

Images (mentioned), Text, Credits: NASA/Tony Greicius/JPL/Elizabeth Landau.

Best regards, Orbiter.ch

Moon Express becomes first private company to receive permission to go to the Moon












Moon Express Mission patch.

August 3, 2016

A US startup has received government approval to send an unmanned on the moon next year capsule.

Moon Express Lunar Lander approaching the Moon

To date only the US government, China and the then Soviet Union sent equipment on the moon.

A US startup called Moon Express received approval from the US Government to send an unmanned on the moon next year capsule, a first for a private company, she said Wednesday.

To date only the US government, China and the then Soviet Union sent equipment on the moon.

A first for a private company

"We are at present free to go explore the" eighth continent "of the Earth, the Moon, to learn and seek resources for the good of all humanity," said Bob Richards, CEO of Moon Express , founded in 2010 and based in Cape Canaveral, Florida (southeast).

The agreement was given by the Federal Agency of Aviation (FAA), which has previously consulted the White House, the State Department and the US space agency (NASA).

Moon Express Lunar Lander Testing Compact Rover

Moon Express has not yet completed construction of its capsule, called MX-1. This will take off the end of 2017 with a rocket produced by Rocket Lab, another start-up, which has currently not yet made trade mission.

"The sky is not the limit for Moon Express"

"The sky is not the limit for Moon Express, is just the launch base," said Naveen Jain, co-founder of Moon Express, which considers the coalition agreement as another "giant leap for mankind" , like the words spoken by astronaut Neil Armstrong during his first steps on the moon.

Let's Create History Together

The aim of the company is to develop a low-cost device space and explore the resources of the Moon.

"In the near future, we want to return to Earth valuable resources, lunar metals and stones," said Mr. Jain.

For more information about Moon Express, visit: http://www.moonexpress.com/

Moon Express YouTube channel: https://www.youtube.com/user/MoonExpressInc

Images, Video, Text, Credits: Moon Express / NXP / ATS / Orbiter.ch Aerospace / Roland Berga.

Greetings, Orbiter.ch

The "Jade Rabbit" completed its mission










CNSA - China National Space Administration logo.

August 3, 2016

The unmanned vehicle sent by Beijing on the moon, was definitely off, said Wednesday the Chinese state media.

 Jade Rabbit on the descent of the lunar lander

The unit was the symbol of the space ambitions of the communist regime. The population was enthusiastic about his prowess, commented extensively on social networks.

The craft unmanned said goodbye after nearly three years of mission marked by several phases of coma.

Designed for operational twelve weeks, the "Jade Rabbit" (Yutu in Mandarin) will be probed and finally walked on the moon in 31 months, linking technical and resurrections to the delight of Chinese Internet users.

The unit, symbol of space ambitions of the communist regime, had become a source of pride in China, where the population is enthusiastic about his prowess, commented extensively on social networks.

But this time the machine finally stopped for good business, said the official Xinhua news agency, citing the State Administration for Science, Technology and Industry at the service of National Defense.

"Great Success"
Half a century after the United States and their Apollo program, China has its eyes fixed on the moon, where she dreams of being the first Asian country to send a human, probably after 2025.

Jade Rabbit

Anxious to improve its technical, China had managed to land on the moon in late 2013 its Chang'e-3 probe (named after the Chinese goddess of the moon) and then land on the surface of the "Bunny jade" qualified assignment "full success".

Comments upset

On an official microblog account, a final message attributed to "Rabbit jade" Sunday offered his moving farewell to mankind: "This time it is 'good night' for ever (...) I am the rabbit which has seen the most stars! Moon said she was preparing me dream for a very long time. "

This message, together with the piece "Universal Traveler" the French group Air, was shared almost 100,000 times and provoked upset comments rains, one promised Yutu of "carrot pies by the millions."

Jade Rabbit rolling on the moon

Another social network user commented: "I do not understand why I have so much heartbroken. After all, it is only a machine. "

Symbol of Power

China spends billions of dollars to the conquest of space, seen as a symbol of the new power of the country under the ruling of the Communist Party.

China now plans to launch by 2018 a rover called Chang'e-4 on the far side of the Moon, which would be a historic first.

For more information about Jade Rabbit an China National Space Administration (CNSA), visit: https://en.wikipedia.org/wiki/China_National_Space_Administration and the official website: http://www.cnsa.gov.cn/

Images, Text, Credits: CNSA/News.cn/Xinhua/NXP/ATS/Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.ch

mardi 2 août 2016

GPM Looks at Historic Flooding from Slow-Moving Maryland Storms













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

Aug. 2, 2016

NASA analyzed rainfall data from slow-moving storms that triggered flash floods over parts of central Maryland and caused devastating flooding in historic Ellicott City, Maryland.

A slow-moving line of heavy thunderstorms dumped as much as 6 to 7 inches of rain in about two hours' time during the evening of Saturday, July 30, over parts of Howard County in central Maryland, resulting in severe local flash flooding.


Image above: This image shows instantaneous IMERG-estimated rainfall rates at 8 p.m. EDT on July 30, 2016. It depicts a strong band of heavy rain (an inch per hour in purple areas) extending east-west over north-central Maryland extending southwestward into northern Virginia. Image Credits: NASA/JAXA/Hal Pierce.

The hardest hit area was the historic town of Ellicott City, where two people were trapped in their cars and drowned. The town suffered substantial damage to many buildings, numerous cars were tossed about, and around 150 people had to be rescued from the downtown area. The heavy rains and flooding were a result of successive waves of rather slow moving storms that merged over the area.

NOAA's National Weather Service (NWS) in Baltimore issued a public information statement about the flooding on July 31, calling it "historic heavy rainfall Saturday in Ellicott City." NWS noted that extremely heavy rain fell and a rain gauge provided by Howard County to the National Weather Service measured 6.5 inches.


Image above: Visualization of the GPM Core Observatory and Partner Satellites. Image Credits: NASA/JAXA.

A warm, humid air mass, a stationary frontal boundary, and rather weak winds aloft set the stage for the slow-moving storms. Earlier in the afternoon, storms formed up and organized along the Appalachian Mountains before moving slowly out across the Piedmont. The Piedmont is a plateau area between the Atlantic coastal plain and the Appalachians.

This slow-moving line triggered new storms along its leading edge and was eventually overtaken by a second line of successive storms moving out from the Appalachians. The result was a mass of heavy raining thunderstorms across central Maryland that slowing moved eastward before weakening over the northern Chesapeake Bay.


Image above: IMERG was also used to estimate rainfall totals for the period from July 30 at 4 p.m. EDT (8 p.m. UTC) to July 31 at 6 a.m. EDT (10 a.m. UTC). Rainfall totals across central Maryland were on the order of more than 70 mm (about 3 inches, shown in brown). The white crosses denote the location of Ellicott City, Maryland. Image Credits: NASA/JAXA/Hal Pierce.

NASA's Integrated Multi-satellite Retrievals for GPM, or IMERG, is used to make estimates of precipitation from a combination of passive microwave sensors, including the GMI microwave sensor on board the GPM, or Global Precipitation Measurement, mission satellite, and geostationary IR (infrared) data. These data were used to create images and animations at NASA's Goddard Space Flight Center in Greenbelt, Maryland. GPM is a joint mission between NASA and the Japan Aerospace Exploration Agency.

One image created showed instantaneous IMERG-estimated rainfall rates at 8 p.m. EDT on July 30 (12 a.m. UTC on July 31), 2016. IMERG showed a strong band of heavy rain extending east-west over north-central Maryland extending southwestward into northern Virginia. Within this band, rain rates are generally on the order of an inch per hour with localized areas of higher rates.


Image above: File photo of The B&O railroad bridge entrance to Ellicott City, Maryland, taken July 2014. Image Credit: courtesy of Rob Gutro.

IMERG was also used to estimate rainfall totals for the period from July 20 at 4 p.m. EDT (8 p.m. UTC) to July 31 at 6 a.m. EDT (10 a.m. UTC). Rainfall totals across central Maryland were on the order of more than 3 inches (70 mm).

On Aug. 1, 2016, because of the severity of the flooding, Howard County Maryland Executive Allan H. Kittleman signed an executive order closing a portion of Ellicott City to all but emergency vehicle and pedestrian traffic. For updated information from Howard County, visit: https://www.howardcountymd.gov/.

For more information about  GPM (Global Precipitation Measurement), visit: http://www.nasa.gov/mission_pages/GPM/main/index.html and http://global.jaxa.jp/projects/sat/gpm/topics.html

Images (mentioned), Text, Credits: NASA's Goddard Space Flight Center/Steve Lang and Rob Gutro/Rob Garner.

Greetings, Orbiter.ch

Aladin wind probe ready for Aeolus












ESA - ADM-AEOLUS Mission patch.

2 August 2016

It has been years in the making, but one of the trickiest pieces of space technology ever developed is finally ready to join its satellite for launch by the end of next year. With this milestone, we are another step closer to a better understanding of Earth’s winds.

Carrying pioneering lasers, Aeolus will be the first satellite to probe the wind globally.

These vertical slices through the atmosphere, along with information on aerosols and clouds, will advance our knowledge of atmospheric dynamics and contribute to climate research.

Profiling the world's winds

Since Aeolus will deliver measurements almost in real time, it is also set to provide much-needed information to improve weather forecasts.

Its state-of-the-art Aladin instrument, which was designed by Airbus Defence and Space in France, incorporates two powerful lasers, a large telescope and very sensitive receivers.

The laser generates ultraviolet light that is beamed towards Earth. This light bounces off air molecules and small particles such as dust, ice and droplets of water in the atmosphere. The fraction of light that is scattered back towards the satellite is collected by Aladin’s telescope and measured.

Prof. Erland Källén, Director of Research at the European Centre for Medium Range Weather Forecasts, said, “The Aeolus mission will provide wind observations that are unique with respect to the current global observing system capabilities.

“The observations fill a gap in the global observing system and despite the many years of delay there is still a need for the mission and we expect it to have a big impact on weather forecasting.

“In the Tropics, wind information dominates atmospheric analyses and this influences the quality of weather forecasts for Europe for the week ahead.

Aladin ready for Aeolus

“Wind information from Aeolus is also expected to be important over oceans in both hemispheres for determining the position and evolution of jet streams and atmospheric fronts.”

Developing advanced new space technologies is never easy and the Aeolus mission has certainly faced its share of challenges.

For instance, the optics have to survive exposure to high-intensity laser pulses for at least three years in the unforgiving environment of space. Developing optics that could withstand these extremes took much longer than anticipated.

Nevertheless, recent tests have shown that such technical problems have been resolved.

Aladin revealed

Frederic Fabre, Project Manager for Aladin at Airbus Defence and Space, said, “This is very good news for the meteorologists and scientists who have been waiting some time for Aladin data to improve weather forecasting.

“The completion of the instrument is a result of the day-to day-involvement of the whole Aladin team including ESA, Airbus Defence & Space and several subcontractors throughout Europe.”

Denny Wernham, ESA’s Aladin Instrument Manager, remarked, “The very successful results on Aladin are testimony to the dedication, determination and expertise of the team in Toulouse, who have overcome many technical hurdles to deliver the instrument to their UK colleagues.

“It is a really tremendous achievement and we would like to congratulate them for all their efforts.”

Related links:

ESA's wind mission / ADM-Aeolus / Earth Explorers: http://www.esa.int/Our_Activities/Observing_the_Earth/The_Living_Planet_Programme/Earth_Explorers/ADM-Aeolus/ESA_s_wind_mission

Selex-ES: http://www.selex-es.com/

Airbus Defence and Space: http://airbusdefenceandspace.com/

Facts and figures:
ADM-Aeolus fact sheet: http://esamultimedia.esa.int/docs/EarthObservation/AEOLUS_factsheet_March2016.pdf

Images, Text, Credits: European Space Agency (ESA)/ATG medialab/Airbus Defence and Space.

Best regards, Orbiter.ch

New Research Reveals Fluctuating Atmosphere of Jupiter’s Volcanic Moon






GEMINI Observatory logo.


Aug. 2, 2016

Jupiter’s volcanic moon Io has a thin atmosphere that collapses in the shadow of Jupiter, condensing as ice, according to a new study by NASA-funded researchers. The study reveals the freezing effects of Jupiter’s shadow during daily eclipses on the moon’s volcanic gases.

“This research is the first time scientists have observed this remarkable phenomenon directly, improving our understanding of this geologically active moon,” said Constantine Tsang, a scientist at the Southwest Research Institute in Boulder, Colorado. The study was published Aug. 2 in the Journal of Geophysical Research.

Image Credit: Gemini North telescope

Io is the most volcanically active object in the solar system. The volcanoes are caused by tidal heating, the result of gravitational forces from Jupiter and other moons. These forces result in geological activity, most notably volcanoes that emit umbrella-like plumes of sulfur dioxide gas that can extend up to 300 miles (480 kilometers) above Io and produce extensive basaltic lava fields that can flow for hundreds of miles.

The new study documents atmospheric changes on Io as the giant planet casts its shadow over the moon’s surface during daily eclipses. Io’s thin atmosphere, which consists primarily of sulfur dioxide (SO2) gas emitted from volcanoes, collapses as the SO2 freezes onto the surface as ice when Io is shaded by Jupiter, then is restored when the ice warms and sublimes (i.e. transforms from solid back to gas) when the moon moves out of eclipse back into sunlight.

The study used the large eight-meter Gemini North telescope in Hawaii and an instrument called the Texas Echelon Cross Echelle Spectrograph (TEXES). Data showed that Io’s atmosphere begins to “deflate” when the temperatures drop from -235 degrees Fahrenheit in sunlight to -270 degrees Fahrenheit during eclipse. Eclipse occurs two hours of every Io day (1.7 Earth days). In full eclipse, the atmosphere effectively collapses, as most of the sulfur dioxide gas settles as frost on the moon’s surface. The atmosphere redevelops as the surface warms once the moon returns to full sunlight.


Image above: Artist’s concept of the atmospheric collapse of Jupiter’s volcanic moon Io, which is eclipsed by Jupiter for two hours of each day (1.7 Earth days). The resulting temperature drop freezes sulfur dioxide gas, causing the atmosphere to “deflate,” as seen in the shadowed area on the left. Image Credits: SwRI/Andrew Blanchard.

“This confirms that Io’s atmosphere is in a constant state of collapse and repair, and shows that a large fraction of the atmosphere is supported by sublimation of SO2 ice,” said John Spencer, a co-author of the new study, also at the Southwest Research Institute. “Though Io’s hyperactive volcanoes are the ultimate source of the SO2, sunlight controls the atmospheric pressure on a daily basis by controlling the temperature of the ice on the surface.  We’ve long suspected this, but can finally watch it happen.”

Prior to the study, no direct observations of Io’s atmosphere in eclipse had been possible because Io’s atmosphere is difficult to observe in the darkness of Jupiter’s shadow.  This breakthrough was possible because TEXES measures the atmosphere using heat radiation, not sunlight, and the giant Gemini telescope can sense the faint heat signature of Io’s collapsing atmosphere.

The observations occurred over two nights in November 2013, when Io was more than 420 million miles (675 million kilometers) from Earth. On both occasions, Io was observed moving into Jupiter’s shadow for a period about 40 minutes before and after the start of the eclipse.

The research was funded by NASA’s Solar System Workings and Solar System Observations programs.

Related links:

Gemini North telescope: http://www.gemini.edu/

Solar System: https://www.nasa.gov/topics/solarsystem/index.html

Planet Jupiter: https://www.nasa.gov/jupiter

Jupiter moon Io: https://www.nasa.gov/subject/3150/io

Images (mentioned), Text, Credits: NASA/Tricia Talbert.

Greetings, Orbiter.ch