samedi 14 avril 2018

ULA - Atlas V 551 launches AFSPC-11


















ULA - Atlas V 551 / AFSPC-11 Mission poster.


April 14, 2018

Atlas V 551 rocket launches the AFSPC-11

A United Launch Alliance (ULA) Atlas V 551 rocket launched the AFSPC-11 mission from Space Launch Complex-41 at Cape Canaveral Air Force Station, Florida, on 14 April 2018, at 23:13 UTC (19:13 EDT).


Atlas V 551 launches AFSPC-11 (CBAS & EAGLE)

Air Force Space Command (AFSPC)-11 mission launched two spacecraft to a geosynchronous transfer orbit: CBAS (Continuous Broadcast Augmenting SATCOM) and EAGLE (ESPA Augmented GEO Laboratory Experiment).

EAGLE satellite

The mission launches the Air Force’s Continuous Broadcast Augmenting SATCOM (CBAS) payload and the EAGLE satellite hosting multiple military experiments. The rocket fly in the 551 vehicle configuration with a five-meter fairing, five solid rocket boosters and a single-engine Centaur upper stage.

Atlas V 551 rocket carrying AFSPC-11 at the launch-pad

The Atlas V 551 rocket is the most powerful in the Atlas V fleet.

For more information about United Launch Alliance (ULA), visit: https://www.ulalaunch.com/

Images, Video, Text, Credits: United Launch Alliance (ULA)/SciNews/Günter Space Page/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

vendredi 13 avril 2018

Space Station Science Highlights: Week of April 9, 2018











ISS - Expedition 55 Mission patch.

April 13, 2018

With the dust settling from the recent arrival of SpaceX CRS-14, the Expedition 55 crew members aboard the International Space Station had a week chock full of new and old science investigations to be commenced, continued and completed.


Image above: Destiny, the U.S. Laboratory aboard the space station. The pink glow from the Veggie plant growth facility in Columbus can be seen ahead in Node 2. Image Credit: NASA.

Take a look at some of the science that happened this week aboard your orbiting laboratory:

Student investigation studies alterations in DNA

Spaceflight causes many changes to the human body, including alterations in DNA and a weakened immune system. Understanding whether these two processes are linked is important for safeguarding crew health. Genes in Space-5, a student-designed investigation, tests whether the polymerase chain reaction (PCR) can be used to study DNA alterations aboard the space station.


Image above: The NASA astronaut Ricky Arnold processes DNA samples in the miniPCR. Image Credit: NASA.

In addition to providing valuable information about maintaining crew health in space, results from Genes in Space-5 provides a deeper understanding of the human immune system on Earth and provides students a direct, hands-on connection to science in space.

This week, the crew processed samples in the miniPCR and then transferred the data for downlink to Earth.

Crew deploys radiation detectors throughout space station

The RaDI-N2 Neutron Field Study (Radi-N2) measures neutron radiation levels aboard the orbiting laboratory using Space Bubble Detectors. Results from this investigation may provide a better understanding of the connections between neutron radiation and DNA damage and mutation rates, symptoms that affect some astronauts, and other radiation health issues on Earth.

International Space Station (ISS). Image Credits: NASA/STS-132

This week, crew members deployed eight Space Bubble Detectors, designed to detect neutrons and ignore all other forms of radiation.

Final harvest completed for VEG-03, facility prepared for APEX-06

Future long-duration missions into the solar system will require a fresh food supply to supplement crew diets, which means growing crops in space.

The Veg-03 investigation expands on previous validation tests of the new Veggie hardware, which crew members used to grow cabbage, lettuce and other fresh vegetables in space. This investigation marked the first time that two grow-outs have been initiated using two Veggie facilities in parallel aboard the space station.

This week, crew members completed the final harvest for the investigation, some for preservation and some for crew consumption.


Image above: NASA astronaut Scott Tingle with the final crops of the VEG-03 investigation. Image Credit: NASA.

The next investigation to be conducted in the Veggie facility is Using Brachypodium distachyon to Investigate Monocot Plant Adaptation to Spaceflight (APEX-06), an investigation which expands our understanding of plant growth in space and provides fundamental information about plant biology on Earth.

Space to Ground: Genes in Space: 04/13/2018

Other work was done on these investigations: Crew Earth Observations, Microbial Tracking-2, CBEF, Biochemical Profile, Polar, Story Time from Space, Plant Gravity Perception, Veg-03, CASIS PCG-9, MSG, CIR, MISSE-FF, SABL, Space Pup, EIISS, EarthKAM, Tango Lab Payload Card-6, Tango Lab-2, Multi-Use Variable-g platform (MVP), Metabolic Tracking, and SPHERES Tether Slosh.

Related links:

SpaceX CRS-14: https://www.nasa.gov/mission_pages/station/research/SpX-14_research_launch_feature

Genes in Space-5: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7656

Space Bubble Detectors: http://www.asc-csa.gc.ca/eng/sciences/osm/detector.asp

RaDI-N2 Neutron Field Study (Radi-N2): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=874

Veggie: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=374

Veg-03: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1159

APEX-06: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7524

Crew Earth Observations: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=84

Microbial Tracking-2: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1663

CBEF: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=333

Biochemical Profile: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=980

Polar: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=1092

Story Time from Space: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1152

Plant Gravity Perception: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=2019

CASIS PCG-9: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7627

MSG: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=341

CIR: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=317

MISSE-FF: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=7515

SABL: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=1148

Space Pup: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=870

EIISS: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7565

EarthKAM: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=87

Tango Lab Payload Card-6: http://www.spacetango.com/blog/2018/4/1/whats-flying-a-look-at-space-tango-crs-14-payloads

Tango Lab-2: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=7519

Multi-Use Variable-g platform (MVP): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=1777

Metabolic Tracking: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7517

SPHERES Tether Slosh: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7381

Expedition 55: https://www.nasa.gov/mission_pages/station/expeditions/expedition55/index.html

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

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

Images (mentioned), Video, Text, Credits: NASA/Michael Johnson/Yuri Guinart-Ramirez, Lead Increment Scientist Expeditions 55 & 56/NASA Johnson.

Best regards, Orbiter.ch

NASA's World Tour of the Atmosphere Reveals Surprises Along the Way












NASA - Airborne Science Program patch.

April 13, 2018


Image above: The DC-8 at sunset on ATom’s second deployment in February, 2017. Image Credts: NASA/Becky Hornbook.

Two thirds of Earth's surface are covered by water — and two thirds of Earth's atmosphere reside over the oceans, far from land and the traditional ways that people measure the gases and pollutants that cycle through the air and around the globe. While satellites in space measuring the major gases can close some of that gap, it takes an aircraft to find out what's really happening in the chemistry of the air above the oceans. That's where NASA's Atmospheric Tomography (ATom) mission comes in.

Since 2016, a team of scientists with 25 advanced instruments aboard NASA's DC-8 research aircraft has sampled over 400 different gases and a broad range of airborne particles on month-long excursions from Alaska down the Pacific to New Zealand, then over to South America and up the Atlantic to Greenland, and across the Arctic Ocean. Far from land, the atmosphere above the ocean is where to find the cleanest air on the planet — at least in theory. Over the course of three deployments, and with their fourth and final trek beginning in late April, the team has found surprising levels of pollutants above the Pacific, Atlantic and Arctic oceans.



Image above: Sea ice in the Arctic as seen from ATom’s DC-8 in January 2017. Image Credits: NASA/Róisín Commane.

"It is astounding to see such dense pollution in the middle of the ocean, so far from the source regions," said ATom's principal investigator Steve Wofsy of Harvard University, recalling their flight up the center of the Atlantic and their stop at Ascension Island halfway between Africa and South America, just south of the equator.

"As we descended the first time, we were stunned to find ourselves in a thick haze of smoke and dust that originated in Africa, thousands of kilometers to the east. The haze had an unappealing yellow-brown hue and was so thick we couldn't see the ocean. All of the hundreds of pollutant chemicals we measure had very high amounts. On each revisit since that first one, we have found a similar pall extending for thousands of kilometers, spanning the entire tropical Atlantic Ocean," he said.

Computer models that simulate the movement of the major gases such as carbon monoxide, created by incomplete combustion from fires, are one of the tools used by the ATom team to get an idea of what they might see on each leg of their flight. It's also one of the tools they are evaluating.

"One of the great things about ATom is showing how well the model generally works," said Paul Newman, chief scientist of Earth science at NASA's Goddard Space Flight Center in Greenbelt, Maryland. The model combines weather forecasts with known atmospheric chemistry to tell them where and when a pollution plume will intersect the flight path. "But it misses a lot of the detail. It’s giving you an understanding of where the stuff is coming from, and that allows you to refine your science. So we’re not out there discovering uncharted lands, but it’s like, I have a map of Iowa, and I’ll drive around there, and that map is probably, depending on how old it is, 95 percent right. It’s the 5 percent wrong that’s interesting."


Animation above: The DC-8 flies this pattern to collect atmospheric samples through the entire column of air. Animation Credits: NASA/Mersmann.

One of those interesting deviations occurred over the Arctic, according to atmospheric scientist and ATom team researcher Róisín Commane at Columbia University in New York City. "One of the largest pollution plumes we've seen wasn't predicted by the models, which came from fires in Siberia. So ATom has given us a snapshot of what we might be missing," she said.

Tracking plumes is only the first step. The next is getting a better understanding of how they change as they linger over the ocean. For example, the hydrocarbons from smoke plumes react in sunlight with other gases to form ozone, a greenhouse gas and air pollutant best known as the main ingredient in city smog. The instruments aboard the DC-8 can detect both ozone itself and all the gases that produce ozone by chemical reactions. This means that in addition to tracking ozone in plumes from land, the ATom team can also determine how much is produced from other gases over the ocean.

The center of the Pacific Ocean is much farther from land than the Atlantic. There, ATom observed generally low ozone levels, but the production of new ozone over the ocean based on the measured suite of ingredient gases was higher than the models predicted.


Image above: Researcher photographing the sea ice as the DC-8 flies over the Arctic January 2017. Image Credits: NASA/ Sam Hall.

"This implies that the remote Pacific is a larger source of tropospheric ozone than we previously understood," said ATom's deputy project scientist Michael Prather at the University of California, Irvine. "It's a preliminary result, and we have yet to analyze whether this produced ozone is natural or related to pollution, but it does mean we'll need to rethink what we believe about how much ozone is produced over the remote oceans, and what that means for the climate and our efforts to reduce ozone pollution on land."

ATom's final deployment will take place this spring. With the atmospheric data they've collected during flights from each season of the year, the science team will continue to analyze the data and improve the atmospheric models that help us understand our home planet.


Animation above: ATom is investigating the atmosphere above the remote oceans. Above the Atlantic ocean near Ascension Island, the research team saw haze from African fires during ATom’s February 2017 flight. Animation Credits: NASA/CI Lab.

ATom is funded by NASA's Earth Venture program and managed by the Earth Science Project Office at NASA’s Ames Research Center in Silicon Valley. The DC-8 research aircraft is managed by NASA's Armstrong Flight Research Center in building 703 in Palmdale, California. A team of over 100 people — scientists, engineers, flight crew and staff — across government agencies and universities support the mission both in the air and from the ground.

To learn more about the ATom mission, visit: https://www.nasa.gov/content/earth-expeditions-atom.

Editor note:

For aviation enthusiasts who own Flight Simulator X on their PCs, here is the link to my add-on NASA DC-8 research aircraft repaint for FSX on my website: https://simulators.jimdo.com/


Images (mentioned), Animations (mentioned), Text, Credits: NASA/Sara Blumberg/NASA's Earth Science News Team, by: Ellen Gray/Orbiter.ch Aerospace.

Greetings, Orbiter.ch

First LHC test collisions of 2018












CERN - European Organization for Nuclear Research logo.

13 Apr 2018

Proton slamming has resumed at the Large Hadron Collider (LHC). Almost a fortnight after the collider began circulating proton beams for the first time in 2018, the machine’s operations team has today steered beams into collision. While these are only test collisions, they are an essential step along the way to serious data taking, which is expected to kick off in early May.


Image above: A test collision recorded by the CMS experiment on 12 April 2018. The CMS collaboration uses these first collisions to prepare for data taking, fine-tuning and powering on various subsystems as needed. (Image: CERN).

Achieving first test collisions is anything but an easy job. It involves round-the-clock checking and rechecking of the thousands of systems that comprise the LHC. It includes ramping up the energy of each beam to the operating value of 6.5 TeV, checking the beams’ instrumentation and optics, testing electronic feedback systems, aligning jaw-like devices called collimators that close around the beams to absorb stray particles and, finally, focusing the beams to make them collide.

Each beam consists of packets of protons called bunches. For these test collisions, each beam contains only two “nominal” bunches, each made up of 120 billion protons. This is far fewer than the 1200 bunches per beam that will mark the start of serious data taking and particle hunting. As the year progresses, the operations team will continue to increase the number of bunches in each beam, up to the maximum of 2556.

Proton particles circulating in Large Hadron Collider (LHC). Animation Credit: CERN

With today’s test collisions, the teams of the experiments located at four collision points around the LHC ring (ALICE, LHCb, CMS and ATLAS) will now be able to check and calibrate their detectors. Stay tuned for the next steps.

Note:

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

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

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.

Related article:

Beams are back in the LHC
http://orbiterchspacenews.blogspot.ch/2018/04/beams-are-back-in-lhc.html

Related links:

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

ALICE: https://home.cern/node/119

LHCb: https://home.cern/node/122

CMS: https://home.cern/node/121

ATLAS: https://home.cern/node/120

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

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

Best regards, Orbiter.ch

Swarm turns to whistlers and storms








ESA - SWARM Mission logo.

13 April 2018

SWARM satellites

The batch of new results from ESA’s Swarm mission has not only included the highest-resolution map of the magnetic field generated by Earth’s crust and a map of the tiny magnetic signals from the oceans, but also, remarkably, some unexpected insight into lightning in the upper atmosphere and geomagnetic storms.

These latest findings are wowing this year’s European Geosciences Union meeting in Vienna, Austria. This week-long event draws scientists from all over the world to share discoveries about our planet.

Electric nature

One of these findings relates to the coupling between the weather we experience on the ground and its counterpart in space.

Discharging massive bursts of electricity, lightning is one of nature’s most dangerous yet beautiful displays. By the laws of physics, the flashes we witness from the ground must also propagate upwards. However, much is yet to be learnt about the other end of a lightning bolt.

Although not designed to do so, it turns out that Swarm can measure this ionospheric counterpart.

We are all used to seeing bursts of light unleased by lightning, but they also carry very low-frequency electromagnetic waves.

Early on in the mission, each of the three Swarm satellites’ magnetometers was run temporarily in a higher frequency mode than normal. Data from this time have been reanalysed and revealed that, surprisingly, the instruments detected these waves. Converted into sound, they are known as whistlers.

Whistlers

The whoosh of these lightning whistlers can be heard in the animation above.

Gauthier Hulot from the Institut de Physique du Globe de Paris said, “Although few whistlers at such unusual frequencies have been measured from space before, Swarm detected some 4000 in just four days, which is a particularly rich dataset.

“This gives us a unique opportunity to investigate the nature of the ionosphere and also see how lightning signals escape the atmosphere and propagate into space.”

In addition, Swarm is now contributing to our understanding of how storms in the upper atmosphere develop.

During a geomagnetic storm, solar wind interacts with Earth’s magnetic field, transferring large amounts of energy into the upper atmosphere in the form of electric currents.

While some of this energy can fuel auroras, most is transferred into heat in a process called Joule heating, which causes the upper atmosphere to expand.

Eelco Doornbos from Delft University of Technology explained, “Swarm has given us a novel view of how this heat is dispersed in the upper atmosphere.

St. Patrick’s Day storm

“The animation shows that when the storm begins, heat enters the auroral zone. In response, the atmospheric gas above the aurora expands and is lifted to higher altitudes. It then falls in waves that cover the entire globe in a matter of hours. This is a truly massive movement of gas in the upper atmosphere.”

Rune Floberghagen, ESA’s Swarm mission manager, noted, “The mission was built to give us new insight into the magnetic field, which it is doing spectacularly.

“And, while it continues to deliver on its promise, we see a steady stream of ground-breaking scientific results that ultimately help us understand the world we live in and the space around it.

“The remarkable results that just keep coming from Swarm never cease to amaze me.”

Related links:

ESA Swarm: http://www.esa.int/Our_Activities/Observing_the_Earth/Swarm

European Geosciences Union General Assembly 2018: https://www.egu2018.eu/

Institut de Physique du Globe de Paris: http://www.ipgp.fr/index2.php

Delft University of Technology: https://www.tudelft.nl/en/

EGU press conference replay:

ESA’s latest satellite data: https://client.cntv.at/egu2018/pc2

Images, Videos, Text, Credits: ESA/M. Lehmann/Institut de Physique du Globe de Paris/TU Delft.

Greetings, Orbiter.ch

jeudi 12 avril 2018

Giving Roots and Shoots Their Space: The Advanced Plant Habitat












ISS- Veggie Mission patch.

April 12, 2018

International Space Station (ISS). Animation Credit: NASA

The Advanced Plant Habitat (APH), a recent addition to the International Space Station, is the largest growth chamber aboard the orbiting laboratory. Roughly the size of a mini-fridge, the habitat is designed to test which growth conditions plants prefer in space and provides specimens a larger root and shoot area. This space in turn will allow a wider variety of crops to grow aboard the station. Thus far, the habitat has been used to grow and study Arabidopsis, small flowering plants related to cabbage and mustard, and Dwarf Wheat.

Its monitoring and environmental control systems regulate temperature, oxygen, and carbon dioxide levels, and the system settings can be adjusted for growing different types of plants. Although the system is largely autonomous, the crew adds water to the chamber and changes atmospheric elements such as an ethylene scrubber, carbon dioxide scrubber & bottles, and filters. All systems can be monitored and controlled from a computer on the ground that interfaces directly with the habitat to relay instructions and detailed adjustments to ensure investigation integrity.


Image above: This image features green Dwarf Wheat and Arabidopsis grown aboard the space station. It was taken from APH’s ground computer by Bryan Onate, who used the PHARMER computer on board station to send the command for an image capture and transfer. Image Credit: Bryan Onate.

Because gravity is a constant downward force on Earth, researchers take advantage of the microgravity environment of the space station to achieve a clearer perspective of plant growth habits. Gravity is one of the major cues plants use to guide their growth, but microgravity can act as a kind of mute button that suppresses the role of gravity, enabling researchers to see what other cues take charge.

The APH also has an upgraded LED system that goes beyond the red, blue and green LEDs used at low, medium and high settings in the Veggie plant habitat. APH is equipped with white, red, blue, green, and far red LEDs and has a wide variety of settings capable of producing light from zero to 1,000 micromoles, a unit of measurement used to describe the intensity of a light source. By expanding the spectrum of light, researchers can broaden the types of plants they study in space and tailor the light to that plant’s unique needs because each of the lights within APH can be set to any level within that range.


Image above: This image features green Dwarf Wheat within APH. The door of the facility has been removed to show the growth chamber within. Image Credit: NASA.

“It’s more of a fine-tuned instrument,” said project manager Bryan Onate. If a team wants a certain amount of light for an investigation, we can provide that.”

Humidity and temperature can also be manipulated to test plant threshold responses for both ideal and inhospitable growth environments.

APH also provides the first true foray into studies involving space-based agricultural cycles. “Not only can we grow small plants, but we will be able to grow seed to seed” said Onate. This means that an entire line of plants could be grow from one seed brought from Earth, creating generations of offspring destined for life among the stars.  “If we can get seeds that are viable in space and grow multiple generations from that one seed, that’s a new capability. And we now have the space to do that kind of testing with APH. We’ve tried to create a little Mother Earth,” adds Onate.


Image above: This image features growth of wheat samples as crew measure height to document final growth. Image Credit: NASA.

Alongside investigations like Veggie-PONDS and Plant Gravity Perception, this new facility sets the stage for a world of growth in space but also holds lessons for intervention gardening here on Earth. In learning more about the conditions plants prefer, botanists here at home may be able to plan new growth strategies for drought and blighted regions or push for the adoption of large-scale automated growth systems in regions with no naturally-arable soil.

Dwarf Wheat Grows in International Space Station’s Advanced Plant Habitat

The APH supports research solicited through NASA Research Announcements (NRAs) that are designed to meet NASA’s goals for the successful completion of exploration missions and the preservation of astronaut health throughout the life of the astronaut. In addition, the facility is available to support commercial and academic U.S. National Laboratory investigations sponsored by the Center for the Advancement of Science in Space.

Related article:

Rooting for Answers: Simulating G-Force to Test Plant Gravity Perception in Mustard Seedlings
http://orbiterchspacenews.blogspot.ch/2018/03/rooting-for-answers-simulating-g-force.html

Related links:

Advanced Plant Habitat (APH): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=2036

Veggie: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=374

Veggie-PONDS: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7581

Plant Gravity Perception: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=2019

U.S. National Laboratory investigations: https://www.nasa.gov/mission_pages/station/research/nlab/research_opportunities

Spot the Station: https://spotthestation.nasa.gov/

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

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

Images (mentioned), Animation (mentioned), Video, Text, Credits: NASA/Michael Johnson/JSC/International Space Station Program Science Office/Morgan McAllister.

Greetings, Orbiter.ch

Crew Researching Plants, Medicine and Unloading New Science from Dragon











ISS - Expedition 55 Mission patch.

April 12, 2018

Today’s research aboard the International Space Station is primarily focusing on how plants react and how medicine works in space. The Expedition 55 crew and robotics controllers are also continuing cargo operations inside and outside the SpaceX Dragon cargo craft.

Flight Engineer Ricky Arnold participated today in the Plant Gravity Perception experiment, one of several ongoing space botany studies. The station crew is helping scientists explore how plants determine which way to grow and perceive light in microgravity. Results may help future astronauts training for longer missions beyond low-Earth orbit learn how to grow crops in space to sustain themselves.


Image above: NASA astronaut and Flight Engineer Ricky Arnold works with the student-designed Genes in Space-5 experiment inside the Harmony module. The genetic research is helping scientists understand the relationship between DNA alterations and weakened immune systems possibly caused by living in space. Image Credit: NASA.

Japanese astronaut Norishige Kanai continued research into how the human body in space metabolizes medicine. NASA astronaut Drew Feustel started operations with the Metabolic Tracking (MT) experiment this morning before handing it off to Kanai. MT is looking at a particular type of medicine and how it interacts with human tissue cultures. Results could improve therapies in space and lead to better, cheaper drugs on Earth.

Scott Tingle of NASA partnered with Arnold today unloading more cargo from Dragon. They continue to unpack several thousand pounds of new science experiments, station hardware and crew supplies.


Image above: Flying over South Dakota, USA, seen by EarthCam on ISS, speed: 27'617 Km/h, altitude: 409,02 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 12, 2018 at 19:37 UTC.

Outside the Dragon in its trunk is the Atmosphere-Space Interactions Monitor (ASIM) experiment that will be robotically removed Friday. Engineers on the ground operating the Canadarm2 will maneuver ASIM, an Earth observation facility, and install it on Europe’s Columbus lab module.

Related links:

Plant Gravity Perception: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=2019

Metabolic Tracking (MT): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7517

Atmosphere-Space Interactions Monitor (ASIM): https://www.nasa.gov/mission_pages/station/research/experiments/2084.html

Expedition 55: https://www.nasa.gov/mission_pages/station/expeditions/expedition55/index.html

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

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

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

Best regards, Orbiter.ch

What in the World is an ‘Exoplanet?’











NASA logo.

April 12, 2018

Step outside on a clear night, and you can be sure of something our ancestors could only imagine: Every star you see likely plays host to at least one planet.


Image above: The Milky Way, our own galaxy, stretches across the sky above the La Silla telescope in Chile. Hidden inside our own galaxy are trillions of planets, most waiting to be found. Image Credits: ESO/S. Brunier.

Step outside on a clear night, and you can be sure of something our ancestors could only imagine: Every star you see likely plays host to at least one planet.

The worlds orbiting other stars are called “exoplanets,” and they come in a wide variety of sizes, from gas giants larger than Jupiter to small, rocky planets about as big around as Earth or Mars. They can be hot enough to boil metal or locked in deep freeze. They can orbit their stars so tightly that a “year” lasts only a few days; they can orbit two suns at once. Some exoplanets are sunless rogues, wandering through the galaxy in permanent darkness.

That galaxy, the Milky Way, is the thick stream of stars that cuts across the sky on the darkest, clearest nights. Its spiraling expanse probably contains about 400 billion stars, our Sun among them. And if each of those stars has not just one planet, but, like ours, a whole system of them, then the number of planets in the galaxy is truly astronomical: We’re already heading into the trillions.


Image above: This rocky super-Earth is an illustration of the type of planets future telescopes, like TESS and James Webb, hope to find outside our solar system.
Image Credits: ESO/M. Kornmesser.

We humans have been speculating about such possibilities for thousands of years, but ours is the first generation to know, with certainty, that exoplanets are really out there. In fact, way out there. Our nearest neighboring star, Proxima Centauri, was recently found to possess at least one planet – probably a rocky one. It’s 4.5 light-years away – more than 25 trillion miles (40 trillion kilometers). The bulk of exoplanets found so far are hundreds or thousands of light-years away.

The bad news: As yet we have no way to reach them, and won’t be leaving footprints on them anytime soon. The good news: We can look in on them, take their temperatures, taste their atmospheres and, perhaps one day soon, detect signs of life that might be hidden in pixels of light captured from these dim, distant worlds.

The first exoplanet to burst upon the world stage was 51 Pegasi b, a “hot Jupiter” 50 light-years away that is locked in a four-day orbit around its star. The watershed year was 1995. All of a sudden, exoplanets were a thing.

Transit Method Single Planet

Video above: When a planet passes directly between its star and an observer, it dims the star’s light by a measurable amount. Video Credits: NASA/JPL-Caltech.

But a few hints had already emerged. A planet now known as Tadmor was detected in 1988, though the discovery was withdrawn in 1992. Ten years later, more and better data showed definitively that it was really there after all.

And a system of three “pulsar planets” also had been detected, beginning in 1992. These planets orbit a pulsar some 2,300 light-years away. Pulsars are the high-density, rapidly spinning corpses of dead stars, raking any planets in orbit around them with searing lances of radiation.

Now we live in a universe of exoplanets. The count of confirmed planets is 3,700, and rising. That’s from only a small sampling of the galaxy as a whole. The count could rise to the tens of thousands within a decade, as we increase the number, and observing power, of robotic telescopes lofted into space.

How did we get here?

We’re standing on a precipice of scientific history. The era of early exploration, and the first confirmed exoplanet detections, is giving way to the next phase: sharper and more sophisticated telescopes, in space and on the ground. They will go broad but also drill down. Some will be tasked with taking an ever more precise population census of these far-off worlds, nailing down their many sizes and types. Others will make a closer inspection of individual planets, their atmospheres, and their potential to harbor some form of life.

Direct imaging of exoplanets – that is, actual pictures – will play an increasingly larger role, though we’ve arrived at our present state of knowledge mostly through indirect means. The two main methods rely on wobbles and shadows. The “wobble” method, called radial velocity, watches for the telltale jitters of stars as they are pulled back and forth by the gravitational tugs of an orbiting planet. The size of the wobble reveals the “weight,” or mass, of the planet.


Animation above: This evocative movie of four planets more massive than Jupiter orbiting the young star HR 8799 is a composite of sorts, including images taken over seven years at the W.M. Keck observatory in Hawaii. Animation Credits: Jason Wang/Christian Marois.

This method produced the very first confirmed exoplanet detections, including 51 Peg in 1995, discovered by astronomers Michel Mayor and Didier Queloz. Ground telescopes using the radial velocity method have discovered nearly 700 planets so far.

But the vast majority of exoplanets have been found by searching for shadows: the incredibly tiny dip in the light from a star when a planet crosses its face. Astronomers call this crossing a “transit.”

The size of the dip in starlight reveals how big around the transiting planet is. Unsurprisingly, this search for planetary shadows is known as the transit method.

NASA’s Kepler space telescope, launched in 2009, has found nearly 2,700 confirmed exoplanets this way. Now in its “K2” mission, Kepler is still discovering new planets, though its fuel is expected to run out soon.

Each method has its pluses and minuses. Wobble detections provide the mass of the planet, but give no information about the planet’s girth, or diameter. Transit detections reveal the diameter but not the mass.

But when multiple methods are used together, we can learn the vital statistics of whole planetary systems – without ever directly imaging the planets themselves. The best example so far is the TRAPPIST-1 system about 40 light-years away, where seven roughly Earth-sized planets orbit a small, red star.

The TRAPPIST-1 planets have been examined with ground and space telescopes. The space-based studies revealed not only their diameters, but the subtle gravitational influence these seven closely packed planets have upon each other; from this, scientists determined each planet’s mass.

So now we know their masses and their diameters. We also know how much of the energy radiated by their star strikes these planets’ surfaces, allowing scientists to estimate their temperatures. We can even make reasonable estimates of the light level, and guess at the color of the sky, if you were standing on one of them. And while much remains unknown about these seven worlds, including whether they possess atmospheres or oceans, ice sheets or glaciers, it’s become the best-known solar system apart from our own.

Where are we going?

The next generation of space telescopes is upon us. First up is the launch of TESS, the Transiting Exoplanet Survey Satellite. This extraordinary instrument will take a nearly full-sky survey of the closer, brighter stars to look for transiting planets. Kepler, the past master of transits, will be passing the torch of discovery to TESS.

TESS, in turn, will reveal the best candidates for a closer look with the James Webb Space Telescope, currently schedule to launch in 2020. The Webb telescope, deploying a giant, segmented, light-collecting mirror that will ride on a shingle-like platform, is designed to capture light directly from the planets themselves. The light then can be split into a multi-colored spectrum, a kind of bar code showing which gases are present in the planet’s atmosphere. Webb’s targets might include “super Earths,” or planets larger than Earth but smaller than Neptune – some that could be rocky planets like super-sized versions of our own.


Image above: An illustration of the different missions and observatories in NASA’s exoplanet program, both present and future. Image Credit: NASA.

Little is known about these big planets, including whether some might be suitable for life. If we’re very lucky, perhaps one of them will show signs of oxygen, carbon dioxide and methane in its atmosphere. Such a mix of gases would remind us strongly of our own atmosphere, possibly indicating the presence of life.

But hunting for Earth-like atmospheres on Earth-sized exoplanets will probably have to wait for a future generation of even more powerful space probes in the 2020s or 2030s.

Thanks to the Kepler telescope’s statistical survey, we know the stars above are rich with planetary companions. And as we stare up at the night sky, we can be sure not only of a vast multitude of exoplanet neighbors, but of something else: The adventure is just beginning.

Related links:

The launch of TESS: https://exoplanets.nasa.gov/news/1495/nasa-prepares-to-launch-next-mission-to-search-sky-for-new-worlds/

James Webb Space Telescope (JWST): https://www.nasa.gov/mission_pages/webb/main/index.html

TESS (Transiting Exoplanet Survey Satellite): http://www.nasa.gov/tess

Kepler and K2: https://www.nasa.gov/mission_pages/kepler/main/index.html

TRAPPIST-1: https://exoplanets.nasa.gov/news/1487/10-things-all-about-trappist-1/

Exoplanets: https://www.nasa.gov/content/the-search-for-life

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

Greetings, Orbiter.ch

Mars impact crater or supervolcano?












ESA - Mars Express Mission patch.

12 April 2018

Mars Express view of Ismenia Patera

These images from ESA’s Mars Express show a crater named Ismenia Patera on the Red Planet. Its origin remains uncertain: did a meteorite smash into the surface or could it be the remnants of a supervolcano?

Ismenia Patera – patera meaning ‘flat bowl’ in Latin – sits in the Arabia Terra region on Mars. This a transition area between the planet’s northern and southern regions – an especially intriguing part of the surface.

Mars’ topography is clearly split into two parts: the northern lowlands and the southern highlands, the latter sitting up to a few kilometres higher. This divide is a key topic of interest for scientists studying the Red Planet. Ideas for how this dramatic split formed suggest either a massive single impact, multiple impacts or ancient plate tectonics as seen on Earth, but its origin remains unclear.

Ismenia Patera in context within Arabia Terra

Ismenia Patera is some 75 km across. Its centre is surrounded by a ring of hills, blocks and lumps of rock thought to have been ejected and flung into the crater by nearby impacts.

The material thrown off from these events also created small dips and depressions that can be seen within Ismenia Patera itself. Gullies and channels snake down from the crater rim to the floor, which is covered by flat, icy deposits that show signs of flow and movement – these are likely akin to rocky, ice-rich glaciers, which have built up over time in the cold and arid climate.

Perspective view of Ismenia Patera

These images were taken on 1 January by the high-resolution stereo camera on Mars Express, which has been circling the planet since 2003.

Such high-resolution and detailed images shed light on numerous aspects of Mars – for example, how the features seen scarring the surface formed in the first place, and how they have evolved in the many millions of years since. This is a key question for Ismenia Patera: how did this depression form?

There are two leading ideas for its formation. One links it to a potential meteorite that collided with Mars. Sedimentary deposits and ice then flowed in to fill the crater until it collapsed to form the fissured, uneven landscape seen today.

The second idea suggests that, rather than a crater, Ismenia Patera was once home to a volcano that erupted catastrophically, throwing huge quantities of magma out into its surroundings and collapsing as a result.

Topographic view of Ismenia Patera

Volcanoes that lose such huge amounts of material in a single eruption are termed supervolcanoes. Scientists remain undecided on whether or not these existed on Mars, but the planet is known to host numerous massive and imposing volcanic structures, including the famous Olympus Mons – the largest volcano ever discovered in the Solar System.

Arabia Terra also shows signs of being the location of an ancient and long-inactive volcanic province. In fact, another supervolcano candidate, Siloe Patera, also lies in Arabia Terra (seen in the context view of Ismenia Patera).

Ismenia Patera in 3D

Certain properties of the surface features seen in Arabia Terra suggest a volcanic origin: for example, their irregular shapes, low topographic relief, their relatively uplifted rims and apparent lack of ejected material that would usually be present around an impact crater.

However, some of these features and irregular shapes could also be present in impact craters that have simply evolved and interacted with their environment in particular ways over time.

More data on the interior and subsurface of Mars will further our understanding and shed light on structures such as Ismenia Patera, revealing more about the planet’s complex and fascinating history.

Related links:

ESA’s Mars Express: http://www.esa.int/Our_Activities/Space_Science/Mars_Express

HRSC at DLR: http://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10364/548_read-400/#/gallery/657

HRSC data viewer: http://hrscview.fu-berlin.de/

Mars Express overview: http://www.esa.int/Our_Activities/Space_Science/Mars_Express_overview

Behind the lens...: http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Behind_the_lens

Frequently asked questions: http://www.esa.int/Our_Activities/Space_Science/Mars_Express/Frequently_asked_questions

Mars Webcam: http://blogs.esa.int/vmc

Images, Text, Credits: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO/NASA MGS MOLA Science Team.

Best regards, Orbiter.ch

mercredi 11 avril 2018

Variety of Life Studied to Benefit Humans on Earth and in Space











ISS - Expedition 55 Mission patch.

April 11, 2018

International Space Station (ISS). Image Credit: NASA

The Expedition 55 crew explored a wide variety of life science today studying how different biological systems are affected by long-term exposure to microgravity. The multi-faceted space residents observed human genetic and tissue samples, rodents and fruit flies aboard the orbital laboratory today.

Flight Engineer Ricky Arnold started his morning gearing up the student-designed Genes in Space-5 experiment. He processed hardware and genetic samples to help scientists understand the relationship between DNA alterations and weakened immune systems possibly caused by living in space.

Arnold later joined fellow NASA astronaut Drew Feustel for ultrasound eye exams with remote assistance from doctors on the ground. Feustel wrapped up his workday checking on fruit flies housed in the Multi-Use Variable-G Platform that enables research into smaller and microscopic organisms.


Image above: Daybreak begins to interrupt this aurora as the International Space Station flies an orbital day pass. Image Credit: NASA.

Norishige Kanai, from the Japan Aerospace Exploration Agency, tended to mice recently launched to space aboard the SpaceX Dragon cargo craft. The rodents are part of the Mouse Stress Defense experiment that tests strategies to counteract microgravity stresses and cell signaling that lead to bone and muscle loss.

Doctors are learning how medicine works in space and what it does inside astronaut’s bodies. NASA Flight Engineer Scott Tingle looked at a particular type of medicine today and how it interacts with human tissue cultures. Results could improve therapies in space and lead to better, cheaper drugs on Earth.

Related links:

Genes in Space-5: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7517

Multi-Use Variable-G Platform: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=1777

How medicine works in space: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7517

Expedition 55: https://www.nasa.gov/mission_pages/station/expeditions/expedition55/index.html

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

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

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

Greetings, Orbiter.ch

NASA’s Juno Mission Provides Infrared Tour of Jupiter’s North Pole












NASA - JUNO Mission logo.

April 11, 2018

Scientists working on NASA’s Juno mission to Jupiter shared a 3-D infrared movie depicting densely packed cyclones and anticyclones that permeate the planet’s polar regions, and the first detailed view of a dynamo, or engine, powering the magnetic field for any planet beyond Earth. Those are among the items unveiled during the European Geosciences Union General Assembly in Vienna, Austria, on Wednesday, April 11.

Low 3-D Flyover of Jupiter’s North Pole in Infrared

Video above: In this animation the viewer is taken low over Jupiter’s north pole to illustrate the 3-D aspects of the region’s central cyclone and the eight cyclones that encircle it. The movie utilizes imagery derived from data collected by the Jovian Infrared Auroral Mapper (JIRAM) instrument aboard NASA's Juno mission during its fourth pass over the massive planet. Infrared cameras are used to sense the temperature of Jupiter’s atmosphere and provide insight into how the powerful cyclones at Jupiter's poles work. In the animation, the yellow areas are warmer (or deeper into Jupiter’s atmosphere) and the dark areas are colder (or higher up in Jupiter’s atmosphere). In this picture the highest “brightness temperature” is around 260K (about -13°C) and the lowest around 190K (about -83°C). The “brightness temperature” is a measurement of the radiance, at 5 µm, traveling upward from the top of the atmosphere towards Juno, expressed in units of temperature.

Juno mission scientists have taken data collected by the spacecraft’s Jovian InfraRed Auroral Mapper (JIRAM) instrument and generated the 3-D fly-around of the Jovian world’s north pole. Imaging in the infrared part of the spectrum, JIRAM captures light emerging from deep inside Jupiter equally well, night or day. The instrument probes the weather layer down to 30 to 45 miles (50 to 70 kilometers) below Jupiter's cloud tops. The imagery will help the team understand the forces at work in the animation – a north pole dominated by a central cyclone surrounded by eight circumpolar cyclones with diameters ranging from 2,500 to 2,900 miles (4,000 to 4,600 kilometers).

“Before Juno, we could only guess what Jupiter’s poles would look like,” said Alberto Adriani, Juno co-investigator from the Institute for Space Astrophysics and Planetology, Rome. “Now, with Juno flying over the poles at a close distance it permits the collection of infrared imagery on Jupiter’s polar weather patterns and its massive cyclones in unprecedented spatial resolution.”

Jupiter’s Dynamo

Video above: NASA’s Juno mission has provided the first view of the dynamo, or engine, powering Jupiter's magnetic field. The new global portrait reveals unexpected irregularities and regions of surprising magnetic field intensity. Red areas show where magnetic field lines emerge from the planet, while blue areas show where they return. As Juno continues its mission, it will improve our understanding of Jupiter's complex magnetic environment.

Another Juno investigation discussed during the media briefing was the team’s latest pursuit of the interior composition of the gas giant. One of the biggest pieces in its discovery has been understanding how Jupiter’s deep interior rotates.

“Prior to Juno, we could not distinguish between extreme models of Jupiter’s interior rotation, which all fitted the data collected by Earth-based observations and other deep space missions,” said Tristan Guillot, a Juno co-investigator from the Université Côte d'Azur, Nice, France. “But Juno is different -- it orbits the planet from pole-to-pole and gets closer to Jupiter than any spacecraft ever before. Thanks to the amazing increase in accuracy brought by Juno’s gravity data, we have essentially solved the issue of how Jupiter’s interior rotates: The zones and belts that we see in the atmosphere rotating at different speeds extend to about 1,900 miles (3,000 kilometers).

“At this point, hydrogen becomes conductive enough to be dragged into near-uniform rotation by the planet’s powerful magnetic field.”

Jupiter North Pole Infrared Flyover

Video above: An infrared view of Jupiter’s North Pole. The movie utilizes imagery derived from data collected by the Jovian Infrared Auroral Mapper (JIRAM) instrument aboard NASA's Juno mission. The images were obtained during Juno’s fourth pass over Jupiter. Infrared cameras are used to sense the temperature of Jupiter’s atmosphere and provide insight into how the powerful cyclones at Jupiter's poles work. In the animation, the yellow areas are warmer (or deeper into Jupiter’s atmosphere) and the dark areas are colder (or higher up in Jupiter’s atmosphere). In this picture the highest “brightness temperature” is around 260K (about -13°C) and the lowest around 190K (about -83°C). The “brightness temperature” is a measurement of the radiance, at 5 µm, traveling upward from the top of the atmosphere towards Juno, expressed in units of temperature.

The same data used to analyze Jupiter’s rotation contain information on the planet’s interior structure and composition. Not knowing the interior rotation was severely limiting the ability to probe the deep interior. “Now our work can really begin in earnest -- determining the interior composition of the solar system’s largest planet,” said Guillot.

At the meeting, the mission’s deputy-principal investigator, Jack Connerney of the Space Research Corporation, Annapolis, Maryland, presented the first detailed view of the dynamo, or engine, powering the magnetic field of Jupiter.

Connerney and colleagues produced the new magnetic field model from measurements made during eight orbits of Jupiter. From those, they derived maps of the magnetic field at the surface and in the region below the surface where the dynamo is thought to originate. Because Jupiter is a gas giant, “surface” is defined as one Jupiter radius, which is about 44,400 miles (71,450 kilometers).

These maps provide an extraordinary advancement in current knowledge and will guide the science team in planning the spacecraft’s remaining observations.

“We’re finding that Jupiter’s magnetic field is unlike anything previously imagined,” said Connerney. “Juno’s investigations of the magnetic environment at Jupiter represent the beginning of a new era in the studies of planetary dynamos.”

The map Connerney’s team made of the dynamo source region revealed unexpected irregularities, regions of surprising magnetic field intensity, and that Jupiter’s magnetic field is more complex in the northern hemisphere than in the southern hemisphere. About halfway between the equator and the north pole lies an area where the magnetic field is intense and positive. It is flanked by areas that are less intense and negative. In the southern hemisphere, however, the magnetic field is consistently negative, becoming more and more intense from the equator to the pole.

Juno spacecraft orbiting Jupiter. Animation Credit: NASA

The researchers are still figuring out why they would see these differences in a rotating planet that’s generally thought of as more-or-less fluid.

“Juno is only about one third the way through its planed mapping mission and already we are beginning to discover hints on how Jupiter’s dynamo works,” said Connerney. “The team is really anxious to see the data from our remaining orbits.” 

Juno has logged nearly 122 million miles (200 million kilometers) to complete those 11 science passes since entering Jupiter's orbit on July 4, 2016. Juno's 12th science pass will be on May 24.

NASA's Jet Propulsion Laboratory, Pasadena, California, manages the Juno mission for the principal investigator, Scott Bolton, of the Southwest Research Institute in San Antonio. Juno is part of NASA's New Frontiers Program, which is managed at NASA's Marshall Space Flight Center in Huntsville, Alabama, for NASA's Science Mission Directorate. The Italian Space Agency (ASI), contributed two instruments, a Ka-band frequency translator (KaT) and the Jovian Infrared Auroral Mapper (JIRAM). Lockheed Martin Space, Denver, built the spacecraft.

https://www.nasa.gov/juno

https://www.missionjuno.swri.edu

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

https://www.facebook.com/NASAJuno

https://www.twitter.com/NASAJuno

More information on Jupiter can be found at: https://www.nasa.gov/jupiter

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

Best regards, Orbiter.ch

SPHERE Reveals Fascinating Zoo of Discs Around Young Stars












ESO - European Southern Observatory logo.

11 April 2018

SPHERE images a zoo of dusty discs around young stars

New images from the SPHERE instrument on ESO’s Very Large Telescope are revealing the dusty discs surrounding nearby young stars in greater detail than previously achieved. They show a bizarre variety of shapes, sizes and structures, including the likely effects of planets still in the process of forming.

The SPHERE instrument on ESO’s Very Large Telescope (VLT) in Chile allows astronomers to suppress the brilliant light of nearby stars in order to obtain a better view of the regions surrounding them. This collection of new SPHERE images is just a sample of the wide variety of dusty discs being found around young stars.

 SPHERE images the edge-on disc around the star GSC 07396-00759

These discs are wildly different in size and shape — some contain bright rings, some dark rings, and some even resemble hamburgers. They also differ dramatically in appearance depending on their orientation in the sky — from circular face-on discs to narrow discs seen almost edge-on.

SPHERE’s primary task is to discover and study giant exoplanets orbiting nearby stars using direct imaging. But the instrument is also one of the best tools in existence to obtain images of the discs around young stars — regions where planets may be forming. Studying such discs is critical to investigating the link between disc properties and the formation and presence of planets.

SPHERE image of the dusty disc around IM Lupi

Many of the young stars shown here come from a new study of T Tauri stars, a class of stars that are very young (less than 10 million years old) and vary in brightness. The discs around these stars contain gas, dust, and planetesimals — the building blocks of planets and the progenitors of planetary systems.

These images also show what our own Solar System may have looked like in the early stages of its formation, more than four billion years ago.

Most of the images presented were obtained as part of the DARTTS-S (Discs ARound T Tauri Stars with SPHERE) survey. The distances of the targets ranged from 230 to 550 light-years away from Earth. For comparison, the Milky Way is roughly 100 000 light-years across, so these stars are, relatively speaking, very close to Earth. But even at this distance, it is very challenging to obtain good images of the faint reflected light from discs, since they are outshone by the dazzling light of their parent stars.

ESOcast 156 Light: Weird and Wonderful Dusty Discs

Another new SPHERE observation is the discovery of an edge-on disc around the star GSC 07396-00759, found by the SHINE (SpHere INfrared survey for Exoplanets) survey. This red star is a member of a multiple star system also included in the DARTTS-S sample but, oddly, this new disc appears to be more evolved than the gas-rich disc around the T Tauri star in the same system, although they are the same age. This puzzling difference in the evolutionary timescales of discs around two stars of the same age is another reason why astronomers are keen to find out more about discs and their characteristics.

Astronomers have used SPHERE to obtain many other impressive images, as well as for other studies including the interaction of a planet with a disc, the orbital motions within a system, and the time evolution of a disc.

The new results from SPHERE, along with data from other telescopes such as ALMA, are revolutionising astronomers’ understanding of the environments around young stars and the complex mechanisms of planetary formation.

More information:

The images of T Tauri star discs were presented in a paper entitled “Disks Around T Tauri Stars With SPHERE (DARTTS-S) I: SPHERE / IRDIS Polarimetric Imaging of 8 Prominent T Tauri Disks”, by H. Avenhaus et al., to appear in in the Astrophysical Journal. The discovery of the edge-on disc is reported in a paper entitled “A new disk discovered with VLT/SPHERE around the M star GSC 07396-00759”, by E. Sissa et al., to appear in the journal Astronomy & Astrophysics.

The first team is composed of Henning Avenhaus (Max Planck Institute for Astronomy, Heidelberg, Germany; ETH Zurich, Institute for Particle Physics and Astrophysics, Zurich, Switzerland; Universidad de Chile, Santiago, Chile), Sascha P. Quanz (ETH Zurich, Institute for Particle Physics and Astrophysics, Zurich, Switzerland; National Center of Competence in Research “PlanetS”), Antonio Garufi (Universidad Autonónoma de Madrid, Madrid, Spain), Sebastian Perez (Universidad de Chile, Santiago, Chile; Millennium Nucleus Protoplanetary Disks Santiago, Chile), Simon Casassus (Universidad de Chile, Santiago, Chile; Millennium Nucleus Protoplanetary Disks Santiago, Chile), Christophe Pinte (Monash University, Clayton, Australia; Univ. Grenoble Alpes, CNRS, IPAG, Grenoble, France), Gesa H.-M. Bertrang (Universidad de Chile, Santiago, Chile), Claudio Caceres (Universidad Andrés Bello, Santiago, Chile), Myriam Benisty (Unidad Mixta Internacional Franco-Chilena de Astronomía, CNRS/INSU; Universidad de Chile, Santiago, Chile; Univ. Grenoble Alpes, CNRS, IPAG, Grenoble, France) and Carsten Dominik (Anton Pannekoek Institute for Astronomy, University of Amsterdam, The Netherlands).

The second team is composed of: E. Sissa (INAF-Osservatorio Astronomico di Padova, Padova, Italy), J. Olofsson (Max Planck Institute for Astronomy, Heidelberg, Germany; Universidad de Valparaíso, Valparaíso, Chile), A. Vigan (Aix-Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille, Marseille, France), J.C. Augereau (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France) , V. D’Orazi (INAF-Osservatorio Astronomico di Padova, Padova, Italy), S. Desidera (INAF-Osservatorio Astronomico di Padova, Padova, Italy), R. Gratton (INAF-Osservatorio Astronomico di Padova, Padova, Italy), M. Langlois (Aix-Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille Marseille, France; CRAL, CNRS, Université de Lyon, Ecole Normale Suprieure de Lyon, France), E. Rigliaco (INAF-Osservatorio Astronomico di Padova, Padova, Italy), A. Boccaletti (LESIA, Observatoire de Paris-Meudon, CNRS, Université Pierre et Marie Curie, Université Paris Diderot, Meudon, France), Q. Kral (LESIA, Observatoire de Paris-Meudon, CNRS, Université Pierre et Marie Curie, Université Paris Diderot, Meudon, France; Institute of Astronomy, University of Cambridge, Cambridge, UK), C. Lazzoni (INAF-Osservatorio Astronomico di Padova, Padova, Italy; Universitá di Padova, Padova, Italy), D. Mesa (INAF-Osservatorio Astronomico di Padova, Padova, Italy; University of Atacama, Copiapo, Chile), S. Messina (INAF-Osservatorio Astrofisico di Catania, Catania, Italy), E. Sezestre (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), P. Thébault (LESIA, Observatoire de Paris-Meudon, CNRS, Université Pierre et Marie Curie, Université Paris Diderot, Meudon, France), A. Zurlo (Universidad Diego Portales, Santiago, Chile; Unidad Mixta Internacional Franco-Chilena de Astronomia, CNRS/INSU; Universidad de Chile, Santiago, Chile; INAF-Osservatorio Astronomico di Padova, Padova, Italy), T. Bhowmik (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), M. Bonnefoy (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), G. Chauvin (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France; Universidad Diego Portales, Santiago, Chile), M. Feldt (Max Planck Institute for Astronomy, Heidelberg, Germany), J. Hagelberg (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), A.-M. Lagrange (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), M. Janson (Stockholm University, Stockholm, Sweden; Max Planck Institute for Astronomy, Heidelberg, Germany), A.-L. Maire (Max Planck Institute for Astronomy, Heidelberg, Germany), F. Ménard (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), J. Schlieder (NASA Goddard Space Flight Center, Greenbelt, Maryland, USA; Max Planck Institute for Astronomy, Heidelberg, Germany), T. Schmidt (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), J. Szulági (Institute for Particle Physics and Astrophysics, ETH Zurich, Zurich, Switzerland; Institute for Computational Science, University of Zurich, Zurich, Switzerland), E. Stadler (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), D. Maurel (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), A. Deboulbé (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), P. Feautrier (Université Grenoble Alpes, CNRS, IPAG, Grenoble, France), J. Ramos (Max Planck Institute for Astronomy, Heidelberg, Germany) and R. Rigal (Anton Pannekoek Institute for Astronomy, Amsterdam, The Netherlands).

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”.

Links:

Research paper (Avenhaus et al.): http://www.eso.org/public/archives/releases/sciencepapers/eso1811/eso1811a.pdf

Research paper (Sissa et al.): http://www.eso.org/public/archives/releases/sciencepapers/eso1811/eso1811b.pdf

SPHERE consortium web page: https://sphere.osug.fr/?lang=en

SPHERE: https://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/sphere/

ESO’s Very Large Telescope (VLT): https://www.eso.org/public/teles-instr/paranal-observatory/vlt/

ALMA: http://eso.org/alma

Images, Text, Credits: ESO/Richard Hook/Max Planck Institute for Astronomy/Henning Avenhaus/INAF - Astronomical Observatory of Padova/Elena Sissa/ESO/H. Avenhaus et al./E. Sissa et al./DARTT-S and SHINE collaborations/Video: ESO, UHD Team, M. Kornmesser, H. Avenhaus et al., E. Sissa et al., DARTT-S, SHINE collaborations, H. Avenhaus et al./E. Sissa et al./DARTT-S and SHINE collaborations/Music: Jon Kennedy/Written by: Stephen Molyneux, Calum Turner and Richard Hook.

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