samedi 7 août 2021

Space Station Science Highlights: Week of August 2, 2021

 







ISS - Expedition 65 Mission patch.


Aug 7, 2021

Crew members aboard the International Space Station conducted scientific investigations during the week of Aug. 2 that included testing a mobile ultrasound device and radio frequency identification tagging and tracking technology, and performance of a student robot-programming challenge.


Image above: This image shows a starry night sky and atmospheric glow blanket above the southeastern African coast as the International Space Station orbited 263 miles above. Image Credit: NASA.

The space station has been continuously inhabited by humans for 20 years, supporting many scientific breakthroughs. The orbiting lab provides a platform for long-duration research in microgravity and for learning to live and work in space, experience that supports Artemis, NASA’s program to go forward to the Moon and on to Mars.

Here are details on some of the microgravity investigations currently taking place:

On-the-spot imaging

Butterfly IQ Ultrasound demonstrates use of a portable ultrasound and a mobile computing device in microgravity. This commercial off-the-shelf technology could provide important medical capabilities for future exploration missions where immediate ground support is not an option. The investigation collects crew feedback on ease of handling and quality of the ultrasound images, including image acquisition, display, and storage. This technology also has potential applications for medical care in remote and isolated settings on Earth. During the week, crew members performed ultrasounds on specific areas of the body.

Tracking down cargo


Image above: Akihiko Hoshide of the Japan Aerospace Exploration Agency (JAXA) configures one of the space station’s resident Astrobees. These robotic free-flyers provide a platform for a variety of investigations aboard the space station, including RFID Recon, a test of technology to identify and locate cargo, and Robo-Pro, a student software programming challenge. Image Credit: NASA.

Radio frequency identification (RFID) tags, a high-tech form of barcodes, are electronic, do not require line-of-sight, and can respond through wireless communication. RFID Recon tests using this technology to identify tagged cargo and determine its location on the space station using a reader and antennas attached to the space station’s free-flying Astrobee robots. While losing items on a spacecraft is always undesirable, in low-Earth orbit, most things can be replaced by regular supply launches. Replacement is impractical or impossible on deep space missions, though. The technology could help crew members find items more quickly and efficiently as well as make possible more efficient packing, reducing launch mass and stowage volume. RFID also has potential benefit on Earth for automation in warehouse operations, shipping and receiving, manufacturing, health care, and other operations. Crew members configured an Astrobee for runs of the technology test during the week.

Learning to program robots

The Japan Aerospace Exploration Agency (JAXA) Robo-Pro Challenge also uses Astrobees, providing students the opportunity to create software programs to control one of the robots. Crew members initiate the programs, which move Astrobee to a target and illuminate it with a laser pointer. Participants receive a score based on how their programs complete each task. The challenge teaches about space robot technology and gives them hands-on experience creating software and observing how it works. Such experience helps build critical skills needed to solve problems on Earth and could encourage students to pursue careers in the space industry or related science, technology, engineering, and mathematics fields. During the week, crew members conducted briefings for running the challenge.

Other investigations on which the crew performed work:

- InSPACE-4 studies using magnetic fields to assemble tiny structures from colloids, or particles suspended in a liquid. Results could provide insight into how to harness nanoparticles to fabricate and manufacture new materials.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7669

- Repository regularly collects biological specimens from crew members before, during, and after flight, archiving them to support current and future study of human physiological changes and adaptation to microgravity and spaceflight.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=954


Image above: Hardware used for ESA EML investigations, including EML Batch 3 - CCEMLCC, which investigates the surface structure of chill-cooled industrial steel alloys. Image Credit: NASA.

- EML Batch 3 - CCEMLCC, an investigation from ESA (European Space Agency), uses the Electromagnetic Levitator (EML) to investigate the surface structure of chill-cooled industrial steel alloys, a class of structural metals with a variety of construction and transport applications.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8596

- The ISS Experience is a virtual reality film series documenting life and research aboard the space station. Filmed over multiple months, it includes crew activities ranging from conducting science experiments to preparing for a spacewalk.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7877

- Cool Flames Investigation with Gases, part of the ACME series of studies, observes chemical reactions of cool flames, which burn at lower temperatures. Nearly impossible to create in Earth’s gravity, cool flames are easily created in microgravity and studying them may improve understanding of combustion and fires on Earth.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8270

- Food Acceptability looks at how the appeal of food changes during long-duration missions. Whether crew members like and actually eat foods directly affects caloric intake and associated nutritional benefits.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7562

Space to Ground: Around the Bend: 08/06/2021

Related links:

Expedition 65: https://www.nasa.gov/mission_pages/station/expeditions/expedition65/index.html

Butterfly IQ Ultrasound: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8211

RFID Recon: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7722

Astrobee: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=1891

Robo-Pro Challenge: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7979

Astrobees: http://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=1891

ISS National Lab: https://www.issnationallab.org/

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

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

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

Images (mentioned), Video (NASA), Text, Credits: NASA/Ana Guzman/John Love, ISS Research Planning Integration Scientist Expedition 65.

Best regards, Orbiter.ch

Tianwen-1 and Zhurong – a new phase of Mars exploration

 







CNSA - Tianwen-1 (天問-1) Mission to Mars logo.

 

August 7, 2021

Tianwen-1 orbiter will go into a new science orbit

As of today, 6 August 2021, the Tianwen-1 orbiter has been in orbit around Mars for 379 days. The Zhurong rover has been on the surface of Mars for 82 Martian days and has traveled 808 meters. So far, the Tianwen-1 orbiter has been acting mainly as a relay satellite for Zhurong’s data.

Tianwen-1 and Zhurong – a new phase of Mars exploration

On 14 August 2021, Zhurong will end its 90 days designed detection phase and the Tianwen-1 orbiter will go into a new science orbit.

Related articles:

Tianwen-1 Mission to Mars - Close-Up of Zhurong’s Parachute
https://orbiterchspacenews.blogspot.com/2021/07/tianwen-1-mission-to-mars-close-up-of.html

Tianwen-1 Mission to Mars - New images from Zhurong
https://orbiterchspacenews.blogspot.com/2021/07/tianwen-1-mission-to-mars-new-images.html

Zhurong landing on Mars & Sounds of Zhurong’s descend onto Mars
https://orbiterchspacenews.blogspot.com/2021/06/zhurong-landing-on-mars-sounds-of.html

Zhurong rover and Tianwen-1 lander on Mars
https://orbiterchspacenews.blogspot.com/2021/06/zhurong-rover-and-tianwen-1-lander-on.html

Tianwen-1 Lander and Zhurong Rover seen by NASA’s Mars Reconnaissance Orbiter
https://orbiterchspacenews.blogspot.com/2021/06/tianwen-1-lander-and-zhurong-rover-seen.html

Zhurong is roving on Mars!
https://orbiterchspacenews.blogspot.com/2021/05/zhurong-is-roving-on-mars.html

Why the China Mars rover’s landing site has geologists excited & Zhurong’s first images from Mars
https://orbiterchspacenews.blogspot.com/2021/05/why-china-mars-rovers-landing-site-has.html

Tianwen-1 orbiter relays Zhurong rover’s data and images
https://orbiterchspacenews.blogspot.com/2021/05/tianwen-1-orbiter-relays-zhurong-rovers.html

Zhurong landed on Mars! The Tianwen-1 rover is on Utopia Planitia (Videos)
https://orbiterchspacenews.blogspot.com/2021/05/zhurong-landed-on-mars-tianwen-1-rover.html

China succeeds in landing its rover on Mars
https://orbiterchspacenews.blogspot.com/2021/05/china-succeeds-in-landing-its-rover-on.html

Related link:

For more information about China National Space Administration (CNSA), visit: http://www.cnsa.gov.cn/

Image, Video, Text, Credits: China Central Television (CCTV)/China National Space Administration (CNSA)/SciNews/Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.ch

CASC - Long March-3B launches ChinaSat-2E (ZhongXing-2E)

 







CASC - China Aerospace Science and Technology Corporation logo.


August 7, 2021

Long March-3B carrying ChinaSat-2E (ZhongXing-2E) ready for launch

A Long March-3B rocket launched the ChinaSat-2E satellite from the Xichang Satellite Launch Center, Sichuan Province, southwest China, on 5 August 2021, at 16:30 UTC (6 August, at 00:30 local time).

Long March-3B launches ChinaSat-2E (ZhongXing-2E)

ChinaSat-2E or ZhongXing-2E (中星2E) is a communications satellite operated by China Satellite Communications. According to official sources, the satellite was placed in the scheduled orbit.

For more information about China Aerospace Science and Technology Corporation (CASC): http://english.spacechina.com/n16421/index.html

Image, Video, Text, Credits: China Central Television (CCTV)/China Academy of Launch Vehicle Technology (CALVT)/China Aerospace Science and Technology Corporation (CASC)/SciNews/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

NASA’s Perseverance Team Assessing First Mars Sampling Attempt

 







NASA - Mars 2020 Perseverance Rover patch.


Aug 7, 2021

Data sent to Earth by NASA’s Perseverance rover after its first attempt to collect a rock sample on Mars and seal it in a sample tube indicate that no rock was collected during the initial sampling activity.


Image above: This image taken by one the hazard cameras aboard NASA’s Perseverance rover on Aug. 6, 2021, shows the hole drilled in what the rover’s science team calls a “paver rock” in preparation for the mission’s first attempt to collect a sample from Mars. Image Credits: NASA/JPL-Caltech.

The rover carries 43 titanium sample tubes, and is exploring Jezero Crater, where it will be gathering samples of rock and regolith (broken rock and dust) for future analysis on Earth.

“While this is not the ‘hole-in-one’ we hoped for, there is always risk with breaking new ground,” said Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate in Washington. “I’m confident we have the right team working this, and we will persevere toward a solution to ensure future success.”

Perseverance’s Sampling and Caching System uses a hollow coring bit and a percussive drill at the end of its 7-foot-long (2-meter-long) robotic arm to extract samples. Telemetry from the rover indicates that during its first coring attempt, the drill and bit were engaged as planned, and post-coring the sample tube was processed as intended.

“The sampling process is autonomous from beginning to end,” said Jessica Samuels, the surface mission manager for Perseverance at NASA’s Jet Propulsion Laboratory in Southern California. “One of the steps that occurs after placing a probe into the collection tube is to measure the volume of the sample. The probe did not encounter the expected resistance that would be there if a sample were inside the tube.”

The Perseverance mission is assembling a response team to analyze the data. One early step will be to use the WATSON (Wide Angle Topographic Sensor for Operations and eNgineering) imager – located at the end of the robotic arm – to take close-up pictures of the borehole. Once the team has a better understanding of what happened, it will be able to ascertain when to schedule the next sample collection attempt.

Perseverance sampling operation. Animation Credits; NASA/JPL-Caltech

“The initial thinking is that the empty tube is more likely a result of the rock target not reacting the way we expected during coring, and less likely a hardware issue with the Sampling and Caching System,” said Jennifer Trosper, project manager for Perseverance at JPL. “Over the next few days, the team will be spending more time analyzing the data we have, and also acquiring some additional diagnostic data to support understanding the root cause for the empty tube.”

Previous NASA missions on Mars have also encountered surprising rock and regolith properties during sample collection and other activities. In 2008, the Phoenix mission sampled soil that was "sticky" and difficult to move into onboard science instruments, resulting in multiple tries before achieving success. Curiosity has drilled into rocks that turned out to be harder and more brittle than expected. Most recently, the heat probe on the InSight lander, known as the “mole,” was unable to penetrate the Martian surface as planned.

“I have been on every Mars rover mission since the beginning, and this planet is always teaching us what we don’t know about it,” said Trosper. “One thing I’ve found is, it’s not unusual to have complications during complex, first-time activities.”

First Science Campaign

Perseverance is currently exploring two geologic units containing Jezero Crater’s deepest and most ancient layers of exposed bedrock and other intriguing geologic features. The first unit, called the “Crater Floor Fractured Rough,” is the floor of Jezero. The adjacent unit, named “Séítah” (meaning “amidst the sand” in the Navajo language), has Mars bedrock as well, and is also home to ridges, layered rocks, and sand dunes.

Recently, the Perseverance science team began using color images from the Ingenuity Mars Helicopter to help scout for areas of potential scientific interest and to look for potential hazards. Ingenuity completed its 11th flight Wednesday, Aug. 4, traveling about 1,250 feet (380 meters) downrange of its current location so that it could provide the project aerial reconnaissance of the southern Séítah area.

The rover’s initial science foray, which spans hundreds of sols (or Martian days), will be complete when Perseverance returns to its landing site. At that point, Perseverance will have traveled between 1.6 and 3.1 miles (2.5 and 5 kilometers) and may have filled up to eight of its sample tubes.

Next, Perseverance will travel north, then west, toward the location of its second science campaign: Jezero Crater’s delta region. The delta is the fan-shaped remains of the confluence of an ancient river and a lake within Jezero Crater. The region may be especially rich in carbonate minerals. On Earth, such minerals can preserve fossilized signs of ancient microscopic life and are associated with biological processes.

More About the Mission

A key objective for Perseverance’s mission on Mars is astrobiology, including the search for signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith.

Subsequent NASA missions, in cooperation with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.

The Mars 2020 Perseverance mission is part of NASA’s Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.

JPL, which is managed for NASA by Caltech in Pasadena, California, built and manages operations of the Perseverance rover.

For more about Perseverance:

https://mars.nasa.gov/mars2020/ and https://nasa.gov/perseverance

Image (mentioned), Animation (mentioned), Text, Credits: NASA/Sean Potter/Karen Fox/Alana Johnson/JPL/DC Agle.

Greetings, Orbiter.ch

ISS orbit altitude correction is scheduled for August 19

 






ROSCOSMOS - Russian Vehicles patch.


August 7, 2021

In order to form ballistic conditions before launching and docking of the Soyuz MS-19 manned transport vehicle, as well as undocking and landing of the Soyuz MS-18 spacecraft, the specialists of the Russian Mission Control Center will correct the orbital altitude of the International Space Station.

According to preliminary data from the ballistic and navigation support service of the TsNIIMash Flight Control Center (part of the Roscosmos State Corporation), on August 19, 2021 at 07:04 Moscow time, the engines of the Zvezda service module will be turned on, which will operate for 47 seconds, and the impulse value will be 0.67 m / s. After this maneuver, the average altitude of the ISS should increase by 1.2 km and amount to 420.84 km.

ISS reboost by Progress MS cargo vehicle. Image Credit: NASA

Currently, the crew of the 65th long-term expedition, consisting of Roscosmos cosmonauts Oleg Novitsky and Peter Dubrov and NASA astronaut Mark Vande Hai, who arrived on April 9, 2021 on the Soyuz MS-18 manned spacecraft, as well as crew members Crew Dragon - NASA astronauts Shane Kimbrow and Megan MacArthur, ESA astronaut Tom Peske and Japan Aerospace Research Agency astronaut Akihiko Hoshide.

One-turn flight scheme to the ISS can be worked out when Progress MS-20 is launched

A single-turn flight scheme (about 2 hours) on the ISS can be tested for the first time when the Progress MS-20 cargo vehicle is launched in the event that its elements are routinely tested within the framework of launches of the two previous “trucks”. The head of the ballistics department of the Rocket and Space Corporation Energia (part of Roscosmos) Rafail Murtazin told TASS about this.

“Formally, it turns out on two more trucks (Progress MS-18 and Progress MS-19), if it is successful, on the third (Progress MS-20) a single-turn scheme could be made,” he said Murtazin.

According to the ballistician, during the Progress MS-17 flight, launched on June 30 from Baikonur, an entry into a coelliptical orbit was worked out, which is necessary for a single-turn rendezvous scheme. The ship was on it for 50 minutes.

Progress MS cargo vehicle. Image Credit: NASA

“The next truck will also fly on a two-day basis. On it we will continue working out: after the first two impulses we will fly in a coelliptical orbit (after the first day), in another day we will move to another coelliptical orbit, so that both after the first and after the second one, we will understand with what accuracy the coelliptical orbit is formed. and the speed of its degradation, ”he said.

In case of successful completion of this stage and with the approval of Roscosmos, explained Murtazin, the final part of the flight can be tested. Now the autonomous rendezvous takes almost one orbit, so it needs to be reduced to 20-25 minutes. “In fact, in this section, somewhere from a distance of 2-2.5 km, speed control relative to the ISS will be carried out,” he added.

Single turn circuit

In April 2019, RSC Energia developed a single-orbit rendezvous scheme for spacecraft with the ISS; for the first time its elements were tested during the flight of the Progress MS-17 spacecraft. Dmitry Rogozin, General Director of Roscosmos, told reporters that a single-turn flight to the ISS could be tested in 2022.

Rafail Murtazin, head of the RSC Energia ballistics department, told TASS that the single-turn scheme assumes that after launching with two pulses, the spacecraft will be in a coelliptical orbit geometrically similar to the ISS orbit. With this approach, when the observation angle of the station from the ship is 23 degrees, the point of fulfillment of the optimal impulse, leading the ship to the vicinity of the station through a half-turn, is uniquely determined.

Related links (in Russian):

ROSCOSMOS Press Relase: https://www.roscosmos.ru/32081/

ROSCOSMOS Press Relase: https://www.roscosmos.ru/32084/

Soyuz MS-18: https://www.roscosmos.ru/tag/sojuz-ms-18/

Progress MS-20: https://www.roscosmos.ru/tag/progress-ms-20/

Expedition 65: https://www.roscosmos.ru/tag/mks-65/

International Space Station (ISS): https://www.roscosmos.ru/tag/mks/

Images (mentioned), Text, Credits: ROSCOSMOS/Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.ch

jeudi 5 août 2021

Science, Spacewalk Work During U.S. Resupply Ship Preps

 







ISS - Expedition 65 Mission patch.


August 5, 2021

The Expedition 65 crew was multi-tasking today working on everything from physics research to U.S. spacesuits to cargo transfers from Russia’s new science module. Meanwhile, Northrop Grumman’s Cygnus space freighter is on track to resupply the International Space Station next week.

Station Flight Engineers Megan McArthur and Thomas Pesquet were back on science duty today conducting more runs for the InSpace-4 space-manufacturing study. The investigation takes place inside the Microgravity Science Glovebox researching ways to harness nanoparticles and develop advanced materials in microgravity to improve space and Earth systems.


 International Space Station (ISS). Animation Credit: NASA

The duo will also be watching Cygnus approach the space station a day-and-a-half after its launch from Virginia on Aug. 10 at 5:56 p.m. EDT. McArthur will command the Canadarm2 robotic arm to grapple Cygnus at 6:10 a.m. on Aug. 12. Pesquet will back her up as he monitors the U.S. cargo craft’s approach and rendezvous.

NASA Flight Engineer Mark Vande Hei joined Commander Akihiko Hoshide gathering spacewalking tools and checking spacesuit tethers inside the U.S. Quest airlock. The crew is ramping up for a spacewalk to prepare the orbital lab’s Port-4 truss structure ahead of the installation of the next set of roll out solar arrays.


Image above: (From left) Astronauts Akihiko Hoshide and Mark Vande Hei install components on a U.S. spacesuit inside the U.S. Quest airlock. Image Credit: NASA.

Throughout Thursday, Flight Engineer Shane Kimbrough worked on three different EXPRESS racks which are refrigerator-sized research devices supporting a wide variety of science experiments. Kimbrough first repaired components with minor damage inside the U.S. Destiny laboratory module’s EXPRESS-11 rack. Afterward, the three-time station visitor removed an incubator from the Kibo laboratory module’s EXPRESS rack-8 and installed it in the Columbus laboratory module’s EXPRESS rack-3.

Cosmonauts Oleg Novitskiy and Pyotr Dubrov continued unpacking hardware delivered inside the new “Nauka” Multipurpose Laboratory Module. Novitskiy also worked on water transfers from the ISS Progress 78 cargo craft while Dubrov photographed microbes growing for a Russian science experiment.

Related links:

Expedition 65: https://www.nasa.gov/mission_pages/station/expeditions/expedition65/index.html

InSpace-4: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7669

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

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

U.S. Quest airlock: https://www.nasa.gov/mission_pages/station/structure/elements/joint-quest-airlock

Port-4 truss structure: https://www.nasa.gov/mission_pages/station/structure/elements/truss-structure

EXPRESS racks: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=598

U.S. Destiny laboratory module: https://www.nasa.gov/mission_pages/station/structure/elements/us-destiny-laboratory

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

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

Columbus laboratory module: https://www.nasa.gov/mission_pages/station/structure/elements/europe-columbus-laboratory

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

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

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

Greetings, Orbiter.ch

NASA’s TESS Tunes into an All-sky ‘Symphony’ of Red Giant Stars

 





NASA - TESS Mission patch.


Aug 5, 2021

Using observations from NASA’s Transiting Exoplanet Survey Satellite (TESS), astronomers have identified an unprecedented collection of pulsating red giant stars all across the sky. These stars, whose rhythms arise from internal sound waves, provide the opening chords of a symphonic exploration of our galactic neighborhood.

TESS primarily hunts for worlds beyond our solar system, also known as exoplanets. But its sensitive measurements of stellar brightness make TESS ideal for studying stellar oscillations, an area of research called asteroseismology.

“Our initial result, using stellar measurements across TESS’s first two years, shows that we can determine the masses and sizes of these oscillating giants with precision that will only improve as TESS goes on,” said Marc Hon, a NASA Hubble Fellow at the University of Hawaii in Honolulu. “What’s really unparalleled here is that TESS’s broad coverage allows us to make these measurements uniformly across almost the entire sky.”

TESS Maps Red Giants Across the Sky

Video above: This visualization shows the new sample of oscillating red giant stars (colored dots) discovered by NASA’s Transiting Exoplanet Survey Satellite. The colors map to each 24-by-96-degree swath of the sky observed during the mission's first two years. The view then changes to show the positions of these stars within our galaxy, based on distances determined by ESA’s (the European Space Agency’s) Gaia mission. The scale shows distances in kiloparsecs, each equal to 3,260 light-years, and extends nearly 20,000 light-years from the Sun. Video Credits: Credit: Kristin Riebe, Leibniz Institute for Astrophysics Potsdam.

Hon presented the research during the second TESS Science Conference, an event supported by the Massachusetts Institute of Technology in Cambridge – held virtually from Aug. 2 to 6 – where scientists discuss all aspects of the mission. The Astrophysical Journal has accepted a paper describing the findings, led by Hon.

Sound waves traveling through any object – a guitar string, an organ pipe, or the interiors of Earth and the Sun – can reflect and interact, reinforcing some waves and canceling out others. This can result in orderly motion called standing waves, which create the tones in musical instruments.

Just below the surfaces of stars like the Sun, hot gas rises, cools, and then sinks, where it heats up again, much like a pan of boiling water on a hot stove. This motion produces waves of changing pressure – sound waves – that interact, ultimately driving stable oscillations with periods of a few minutes that produce subtle brightness changes. For the Sun, these variations amount to a few parts per million. Giant stars with masses similar to the Sun’s pulsate much more slowly, and the corresponding brightness changes can be hundreds of times greater.

Oscillations in the Sun were first observed in the 1960s. Solar-like oscillations were detected in thousands of stars by the French-led Convection, Rotation and planetary Transits (CoRoT) space telescope, which operated from 2006 to 2013. NASA’s Kepler and K2 missions, which surveyed the sky from 2009 to 2018, found tens of thousands of oscillating giants. Now TESS extends this number by another 10 times.

“With a sample this large, giants that might occur only 1% of the time become pretty common,” said co-author Jamie Tayar, a Hubble Fellow at the University of Hawaii. “Now we can start thinking about finding even rarer examples.”

The physical differences between a cello and a violin produce their distinctive voices. Similarly, the stellar oscillations astronomers observe depend on each star’s interior structure, mass, and size. This means asteroseismology can help determine fundamental properties for large numbers of stars with accuracies not achievable in any other way.

Tuning Into a Trio of Red Giants

Video above: Listen to the rhythms of three red giants in the constellation Draco, as determined by brightness measurements from NASA’s Transiting Exoplanet Survey Satellite. To produce audible tones, astronomers multiplied the oscillation frequencies of the stars by 3 million times. It’s clear that larger stars produce longer, deeper pulsations than smaller ones. Video Credits: NASA/MIT/TESS and Ethan Kruse (USRA), M. Hon et al., 2021.

When stars similar in mass to the Sun evolve into red giants, the penultimate phase of their stellar lives, their outer layers expand by 10 or more times. These vast gaseous envelopes pulsate with longer periods and larger amplitudes, which means their oscillations can be observed in fainter and more numerous stars.

TESS monitors large swaths of the sky for about a month at a time using its four cameras. During its two-year primary mission, TESS covered about 75% of the sky, each camera capturing a full image measuring 24-by-24 degrees every 30 minutes. In mid-2020, the cameras began collecting these images at an even faster pace, every 10 minutes.


Image above: Red giant stars near and far sweep across the sky in this illustration. Measurements from NASA’s Transiting Exoplanet Survey Satellite have identified more than 158,000 pulsating red giants across nearly the entire sky. Such discoveries hold great potential for exploring the detailed structure of our home galaxy. Image Credits: NASA’s Goddard Space Flight Center/Chris Smith (KBRwyle).

The images were used to develop light curves – graphs of changing brightness – for nearly 24 million stars over 27 days, the length of time TESS stares at each swath of the sky. To sift through this immense accumulation of measurements, Hon and his colleagues taught a computer to recognize pulsating giants. The team used machine learning, a form of artificial intelligence that trains computers to make decisions based on general patterns without explicitly programming them.

To train the system, the team used Kepler light curves for more than 150,000 stars, of which some 20,000 were oscillating red giants. When the neural network finished processing all of the TESS data, it had identified a chorus of 158,505 pulsating giants.

Next, the team found distances for each giant using data from ESA’s (the European Space Agency’s) Gaia mission, and plotted the masses of these stars across the sky. Stars more massive than the Sun evolve faster, becoming giants at younger ages. A fundamental prediction in galactic astronomy is that younger, higher-mass stars should lie closer to the plane of the galaxy, which is marked by the high density of stars that create the glowing band of the Milky Way in the night sky.


Animation above: NASA’s Transiting Exoplanet Survey Satellite (TESS) imaged about 75% of the sky during its two-year-long primary mission. This plot dissolves between the TESS sky map and a “mass map” constructed by combining TESS measurements of 158,000 oscillating red giant stars with their distances, established by ESA’s (the European Space Agency’s) Gaia mission. The prominent band in both images is the Milky Way, which marks the central plane of our galaxy. In the mass map, green, yellow, orange, and red show where giant stars average more than 1.4 times the Sun’s mass. Such stars evolve faster than the Sun, becoming giants at younger ages. The close correspondence of higher-mass giants with the plane of the Milky Way, which contains our galaxy's spiral arms, demonstrates that it contains many young stars. Animation Credits: NASA/MIT/TESS and Ethan Kruse (USRA), M. Hon et al., 2021.

“Our map demonstrates for the first time empirically that this is indeed the case across nearly the whole sky,” said co-author Daniel Huber, an assistant professor for astronomy at the University of Hawaii. “With the help of Gaia, TESS has now given us tickets to a red giant concert in the sky.”

TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA's Goddard Space Flight Center. Additional partners include Northrop Grumman, based in Falls Church, Virginia; NASA’s Ames Research Center in California’s Silicon Valley; the Center for Astrophysics | Harvard & Smithsonian in Cambridge, Massachusetts; MIT’s Lincoln Laboratory; and the Space Telescope Science Institute in Baltimore. More than a dozen universities, research institutes, and observatories worldwide are participants in the mission.

Related links:

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

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

Image (mentioned), Animation (mentioned), Videos (mentioned), Text, Credits: NASA/GSFC/By Francis Reddy.

Best regards, Orbiter.ch

NASA Begins Recruitment for Long-Duration Mars Mission Analog Study

 






NASA logo.


Aug 5, 2021

As NASA ventures farther into the cosmos, the astronaut experience will change. In preparation for the real-life challenges of future missions to Mars, NASA will study how highly motivated individuals respond under the rigor of a long-duration, ground-based simulation.


Image above: Mars Dune Alpha Conceptual Render: Visualization on Mars. Image Credit: ICON.

NASA is now accepting applications for participation as a crew member during the first one-year analog mission in a habitat that will simulate stressors of deep space, set to begin in Fall 2022.

Known as Crew Health and Performance Exploration Analog (CHAPEA), the series of missions includes three one-year Mars surface simulations based at NASA’s Johnson Space Center. The analogs will support research to develop methods and technologies to prevent and resolve potential problems on future human spaceflight missions to the Moon and Mars.

Each mission will consist of four crew members in a 1,700-square-foot 3D-printed habitation module, called Mars Dune Alpha. The habitat will simulate the challenges of a mission on Mars, including resource limitations, equipment failure, communication delays, and other environmental stressors. Crew tasks may include simulated spacewalks, scientific research, use of virtual reality and robotic controls, and exchanging communications. The results will provide important scientific data to validate systems and develop solutions.

NASA is looking for healthy, motivated U.S. citizens or permanent residents who are non-smokers, age 30 to 55 years old, and proficient in English for effective communication between crew and mission control. Crew selection will follow standard NASA criteria for astronaut candidate applicants.

A master’s degree in a STEM field such as engineering, mathematics, or biological, physical or computer science from an accredited institution with at least two years of professional STEM experience or a minimum of one thousand hours piloting an aircraft is required. Candidates who have completed two years of work toward a doctoral program in STEM, or completed a medical degree, or a test pilot program will also be considered. Additionally, with four years of professional experience, applicants who have completed military officer training or a Bachelor of Science in a STEM field may be considered.

If you have a strong desire for unique, rewarding adventures and are interested in contributing to NASA’s work in preparing for the first human journey to Mars, click link below to learn more and apply. Compensation for participating in the mission is available. More information will be provided during the candidate screening process.

https://www.nasa.gov/chapea/participate

The United States is called upon to lead the return of humans to the Moon for long-term exploration and then send humans to Mars and other deep space destinations. Through Artemis, NASA will land the next American astronauts, including the first woman and the first person of color, on the Moon. At the Moon, NASA and its partners will implement innovative new partnerships, technologies and systems to study and explore more of the lunar surface than ever before. Lessons learned in space and on the ground will prepare NASA to take the next giant leap – sending astronauts to Mars.

https://www.nasa.gov/chapea

Advanced Exploration Systems (AES) is charged with planning and conducting Artemis missions beginning with Artemis III. This will include landing the first woman and first person of color on the Moon, as well as future long-duration missions building up to a sustainable presence on the lunar surface and in orbit. AES is developing the lunar-orbiting Gateway, exploration spacesuits, the Human Landing System (HLS), surface mobility systems (rovers), and all capabilities required to keep astronauts safe and healthy.

https://www.nasa.gov/directorates/heo/aes/index.html

Image (mentioned), Text, Credits: NASA/Kelli Mars.

Best regards, Orbiter.ch

Huge Rings Around a Black Hole

 







NASA - Chandra X-ray Observatory patch.


Aug 5, 2021


A spectacular set of rings around a black hole has been captured using NASA's Chandra X-ray Observatory and Neil Gehrels Swift Observatory. The X-ray images of the giant rings have revealed new information about dust located in our Galaxy, using a similar principle to the X-rays performed in doctor's offices and airports.

The black hole is part of a binary system called V404 Cygni, located about 7,800 light-years away from Earth. The black hole is actively pulling material away from a companion star — with about half the mass of the Sun — into a disk around the invisible object. This material glows in X-rays, so astronomers refer to these systems as "X-ray binaries."

On June 5 2015, Swift discovered a burst of X-rays from V404 Cygni. The burst created the high-energy rings from a phenomenon known as light echoes. Instead of sound waves bouncing off a canyon wall, the light echoes around V404 Cygni were produced when a burst of X-rays from the black hole system bounced off of dust clouds between V404 Cygni and Earth. Cosmic dust is not like household dust but is more like smoke, and consists of tiny, solid particles.

In a new composite image, X-rays from Chandra (light blue) have been combined with optical data from the Pan-STARRS telescope on Hawaii that show the stars in the field of view. The image contains eight separate concentric rings. Each ring is created by X-rays from V404 Cygni flares observed in 2015 that reflect off different dust clouds. (An artist's illustration explains how the rings seen by Chandra and Swift were produced. To simplify the graphic, the illustration shows only four rings instead of eight.)


Image above: This artist's illustration shows in detail how the ringed structure seen by Chandra and Swift is produced. Each ring is caused by X-rays bouncing off of different dust clouds. If the cloud is closer to us, the ring appears to be larger. The result is a set of concentric rings with different apparent sizes depending on the distance of the intervening cloud from us. Image Credits: Univ. of Wisconsin-Madison/S.Heinz.

The team analyzed 50 Swift observations made in 2015 between June 30 and August 25. Chandra observed the system on July 11 and 25. It was such a bright event that the operators of Chandra purposely placed V404 Cygni in between the detectors so that another bright burst would not damage the instrument.

The rings tell astronomers not only about the black hole's behavior, but also about the landscape between V404 Cygni and Earth. For example, the diameter of the rings in X-rays reveals the distances to the intervening dust clouds the light ricocheted off. If the cloud is closer to Earth, the ring appears to be larger and vice versa. The light echoes appear as narrow rings rather than wide rings or haloes because the X-ray burst lasted only a relatively short period of time.

The researchers also used the rings to probe the properties of the dust clouds themselves. The authors compared the X-ray spectra — that is, the brightness of X-rays over a range of wavelengths — to computer models of dust with different compositions. Different compositions of dust will result in different amounts of the lower energy X-rays being absorbed and prevented from being detected with Chandra. This is a similar principle to how different parts of our body or our luggage absorb different amounts of X-rays, giving information about their structure and composition.

Chandra X-ray Observatory. Animation Credits: NASA/CXC

The team determined that the dust most likely contains mixtures of graphite and silicate grains. In addition, by analyzing the inner rings with Chandra, they found that the densities of the dust clouds changes are not uniform in all directions. Previous studies have assumed that they did not.

This result is related to a similar finding of the X-ray binary Circinus X-1, which contains a neutron star rather than a black hole, published in a paper in the June 20, 2015, issue of The Astrophysical Journal, titled, "Lord of the Rings: A Kinematic Distance to Circinus X-1 from a Giant X-Ray Light Echo" (preprint). This study was also led by Sebastian Heinz.

The V404 Cygni results were led by the same astronomer, Sebastian Heinz of the University of Wisconsin in Madison. This paper was published in the July 1, 2016 issue of The Astrophysical Journal (preprint). The co-authors of the study are Lia Corrales (University of Michigan); Randall Smith (Center for Astrophysics | Harvard & Smithsonian); Niel Brandt (The Pennsylvania State University); Peter Jonker (Netherlands Institute for Space Research); Richard Plotkin (University of Nevada, Reno) and Joey Neilson (Villanova University).

NASA's Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory's Chandra X-ray Center controls science from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.

Image Credits: X-ray: NASA/CXC/U.Wisc-Madison/S. Heinz et al.; Optical/IR: Pan-STARRS

Read more from NASA's Chandra X-ray Observatory: https://chandra.harvard.edu/photo/2021/v404cyg/

For more Chandra images, multimedia and related materials, visit: http://www.nasa.gov/chandra

The Astrophysical Journal: https://arxiv.org/abs/1605.01648

Images (mentioned), Animation (mentioned), Text, Credits: NASA/Lee Mohon.

Greetings, Orbiter.ch

Curiosity Celebrates Another Year on Mars

 







NASA - Mars Science Laboratory (MSL) patch.


Aug 5, 2021


On Aug. 5, 2012, NASA's Curiosity Mars rover landed safely on the Red Planet.

In this self-portrait from 2018, Curiosity sits atop Vera Rubin Ridge, which the rover had been investigating. Directly behind the rover is the start of a clay-rich slope scientists are eager to begin exploring. In the coming week, Curiosity will begin to climb this slope. North is on the left and west is on the right, with Gale Crater's rim on the horizon of both edges.

Poking up just behind Curiosity's mast is Mount Sharp, photobombing the robot's selfie. Curiosity landed on Mars five years ago with the intention of studying lower Mount Sharp, where it will remain for all of its time on Mars. The mountain's base provides access to layers formed over millions of years. These layers formed in the presence of water—likely due to a lake or lakes that sat at the bottom of the mountain, which sits inside Gale Crater.

This mosaic was assembled from dozens of images taken by Curiosity's Mars Hands Lens Imager on Jan. 23, 2018, during Sol 1943.

Mars Science Laboratory (MSL) "Curiosity": https://www.nasa.gov/mission_pages/msl/index.html

Image, Text, Credits: NASA/JPL-Caltech/MSSS/Yvette Smith.

Greetings, Orbiter.ch

10 Years Ago: Juno Launched to Observe Jupiter

 







NASA - JUNO Mission logo.


Aug 5, 2021

On Aug. 5, 2011, NASA’s Juno spacecraft launched on a five-year interplanetary journey that took it to the giant planet Jupiter. NASA’s Jet Propulsion Laboratory in Pasadena, California, manages the Juno mission and its operations. The goal of the spacecraft was to enter orbit around the planet and use its suite of scientific instruments and cameras to observe Jupiter’s atmosphere, gravity and magnetic fields. The understanding of the planet’s properties can reveal clues about its origins and evolution. Juno arrived at Jupiter in July 2016 and entered an elliptical polar orbit around the planet. It continues its observations of the largest planet in our solar system, returning spectacular images of the gas giant, even to this day.

Illustration of Juno in orbit around Jupiter.

Jupiter is a gas giant planet so large that all other objects in the solar system, except the Sun, could fit inside it. With 79 moons orbiting around the planet, the Jovian system is like a mini solar system. Even though Jupiter is one of five planets in our solar system visible to the naked eye, its moons stayed undetected until 1610 when Italian astronomer Galileo Galilei observed Jupiter’s four biggest moons using his homemade telescope. Today, they're referred to as Galilean satellites, named after their discoverer. Over the centuries, progressively better telescopes, and later other instruments, uncovered some of Jupiter’s mysteries, such as its Great Red Spot and multicolored bands in its atmosphere. Our knowledge of the planet increased manifold with the first spacecraft flyby encounters in the 1970s, (Pioneer 10 and 11 and Voyager 1 and 2) especially with the Galileo orbiter and atmospheric probe in the 1990s and 2000s. Several other spacecraft (Ulysses, Cassini-Huygens, and New Horizons) made observations of the giant planet while using its gravity to speed them to other destinations in the solar system. Unlike previous spacecraft that have visited Jupiter, Juno relies on solar rather than nuclear power, carrying a trio of the largest solar panels ever placed on an interplanetary spacecraft.

Schematic illustration of Juno and its suite of scientific instruments.

To perform its observations, Juno carries a suite of nine instruments:

- Microwave Radiometer (MWR): To measure the abundance of water and ammonia in the deep layers of Jupiter’s atmosphere and to obtain a temperature profile of the atmosphere.

- Jovian Infrared Auroral Mapper (JIRAM): A spectrometer to provide images of auroras in Jupiter’s upper atmosphere.

- Magnetometer (MAG): To map Jupiter’s magnetic field and to determine the dynamics of the planet’s interior.

- Gravity Science (GS): To map the distribution of mass inside Jupiter by measuring Doppler changes in the spacecraft’s radio signals.

- Jovian Auroral Distributions Experiment (JADE): To measure the angular distribution, energy, and the velocity vector of ions and electrons at low energy present in the aurora of Jupiter.

- Jovian Energetic Particle Detector Instrument (JEDI): To measure the angular distribution, energy, and the velocity vector of ions and electrons at high energy present in the aurora of Jupiter.

- Radio and Plasma Wave Sensor (Waves): To identify the regions of auroral currents that define Jovian radio emissions and acceleration of the auroral particles.

- Ultraviolet Spectrograph (UVS): To provide spectral images of the ultraviolet auroral emissions in the polar magnetosphere.

- JunoCam (JCM): A visible light camera/telescope to study the dynamics of Jupiter’s clouds, and to facilitate education and outreach.


Above: The plaque provided by the Italian Space Agency to commemorate Italian astronomer
Galileo Galilei, affixed to the Juno spacecraft. Below: The three LEGO figurines depicting the Roman god Jupiter, his wife Juno, and astronomer Galileo, affixed to the Juno spacecraft.

In addition to its scientific instruments, Juno carries two items of historical and educational significance. A plaque provided by the Italian Space Agency depicts a portrait of Galileo and a text in Galileo's own handwriting, penned in January 1610, while observing what would later be known as the Galilean moons, Jupiter’s four largest natural satellites. As part of a joint outreach and educational program between NASA and the LEGO Group to inspire children to explore science, technology, engineering and mathematics, the Juno spacecraft carries three LEGO mini-figurines representing the Roman god Jupiter, his wife Juno, and Galileo, carrying a telescope.


Above: Launch of Juno on Aug. 5, 2011. Middle: Trajectory of Juno from Earth to Jupiter.
Below: Image of Earth taken by Juno during its Oct. 9, 2013 gravity-assist flyby.

The Juno spacecraft launched on Aug. 5, 2011, from the Cape Canaveral Air Force Station, now the Cape Canaveral Space Force Station in Florida, atop an Atlas V 551 rocket. After a 45-minute coast in a parking orbit, the rocket’s Centaur upper stage ignited for a second time to send Juno on its interplanetary journey. The spacecraft unfurled its three large solar arrays to power its systems. It completed its first mid-course correction maneuver on Feb. 1, 2012, followed by two deep-space maneuvers on Aug. 30 and Sept. 14 before looping back toward the inner solar system. On Oct. 9, 2013, Juno passed within 345 miles of Earth, making its closest approach off the coast of South Africa. Although the main purpose of the Earth flyby was to increase Juno’s velocity from 78,000 miles per hour to 93,000 miles per hour to send it toward Jupiter, mission controllers activated several of the spacecraft’s instruments. After an additional course correction on Feb. 3, 2016, on May 27 Juno crossed from the Sun’s gravitational sphere of influence into Jupiter’s, and on June 30 entered Jupiter’s vast magnetosphere.


Composite of JunoCam images taken on July 10, 2016, six days after Juno entered orbit, showing Jupiter, left, and its moons Io, Europa, and Ganymede from 2.7 million miles.


Above: Infrared image of Jupiter’s aurora australis, or southern lights, taken during the first close approach to the planet, or perijove 1, in August 2016. Middle: First view of Jupiter’s south pole from 58,700 miles during perijove 1. Below: View of cloud patterns near Jupiter’s north pole taken during perijove 7 in July 2017.

On July 4, 2016, after a five-year cruise from Earth, Juno fired its main engine for 35 minutes to enter an elliptical polar orbit around Jupiter with an initial period of 53 days. Controllers began to activate Juno’s instruments over the ensuing days and weeks. On Aug. 27, the spacecraft made its first close pass, or perijove, at 2,610 miles above Jupiter’s cloud tops with its entire suite of instruments activated. During its second close approach on Oct. 19, the spacecraft entered a safe mode due to an anomaly affecting its main engine. The anomaly prevented the firing of the main engine to change the spacecraft’s trajectory to the planned 14-day orbit for science observations. Despite this problem, Juno continued its scientific mission in the original 53-day orbit, with the main change being that closeup observations occur less frequently than anticipated. Despite the extreme radiation environment around Jupiter, especially harsh during the perijove encounters, Juno’s systems and instruments remained healthy. In June 2018, NASA extended Juno’s mission to July 2021.


Above: True color image of Jupiter’s Great Red Spot taken during perijove 7 in July 2017. Below: Composite image showing the entire planet centered on mid-southern latitudes with the Great Red Spot visible at upper right, taken during perijove 21 in July 2019.


Above: String of pearls cloud formations captured by Juno during perijove 6 in May 2017. Below: Tumultuous cloud formations in Jupiter’s mid-northern latitudes during perijove 20 in May 2019.


Above: Jupiter’s moon Io casting a shadow on the planet, imaged by Juno at perijove 22 in September 2019. Below: View of Jupiter’s largest moon Ganymede taken during the perijove 34 encounter in June 2021.

On June 7, 2021, during its perijove 34 encounter, Juno flew within 645 miles of Ganymede, Jupiter’s largest moon and in fact the largest moon in the solar system. It was the closest spacecraft encounter since the Galileo spacecraft flew by Ganymede in May 2000. With Juno still healthy, and to meet scientists’ request to study Jupiter’s large Moons, NASA granted a second mission extension to September 2025. Ganymede’s gravity altered Juno’s orbit, reducing its period from 53 days to 43 days and setting up a future encounter with Europa in September 2022. That flyby will reduce Juno’s orbital period to 38 days and set up encounters with Io in December 2023 and February 2024, further reducing the spacecraft’s orbital period to 33 days. Juno continues to return spectacular images of and scientific information about Jupiter and its environment.

Related link:

Juno: http://www.nasa.gov/mission_pages/juno/main/index.html

Images, Text, Credits: NASA/Kelli Mars/JSC/John Uri.

Greetings, Orbiter.ch

New ESO observations show rocky exoplanet has just half the mass of Venus

 







ESO - European Southern Observatory logo.


August 5, 2021

A team of astronomers have used the European Southern Observatory’s Very Large Telescope (ESO’s VLT) in Chile to shed new light on planets around a nearby star, L 98-59, that resemble those in the inner Solar System. Amongst the findings are a planet with half the mass of Venus — the lightest exoplanet ever to be measured using the radial velocity technique — an ocean world, and a possible planet in the habitable zone.

Artist’s impression of the L 98-59 planetary system

"The planet in the habitable zone may have an atmosphere that could protect and support life,” says María Rosa Zapatero Osorio, an astronomer at the Centre for Astrobiology in Madrid, Spain, and one of the authors of the study published today in Astronomy & Astrophysics.

The results are an important step in the quest to find life on Earth-sized planets outside the Solar System. The detection of biosignatures on an exoplanet depends on the ability to study its atmosphere, but current telescopes are not large enough to achieve the resolution needed to do this for small, rocky planets. The newly studied planetary system, called L 98-59 after its star, is an attractive target for future observations of exoplanet atmospheres. Its orbits a star only 35 light-years away and has now been found to host rocky planets, like Earth or Venus, which are close enough to the star to be warm.

Comparison of the L 98-59 exoplanet system with the inner Solar System

With the contribution of ESO’s VLT, the team was able to infer that three of the planets may contain water in their interiors or atmospheres. The two planets closest to the star in the L 98-59 system are probably dry, but might have small amounts of water, while up to 30% of the third planet’s mass could be water, making it an ocean world.

Furthermore, the team found “hidden” exoplanets that had not previously been spotted in this planetary system. They discovered a fourth planet and suspect there is a fifth, in a zone at the right distance from the star for liquid water to exist on its surface. “We have hints of the presence of a terrestrial planet in the habitable zone of this system,” explains Olivier Demangeon, a researcher at the Instituto de Astrofísica e Ciências do Espaço, University of Porto in Portugal and lead author of the new study.

Artist’s impression of L 98-59b

The study represents a technical breakthrough, as astronomers were able to determine, using the radial velocity method, that the innermost planet in the system has just half the mass of Venus. This makes it the lightest exoplanet ever measured using this technique, which calculates the wobble of the star caused by the tiny gravitational tug of its orbiting planets.

The team used the Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations (ESPRESSO) instrument on ESO’s VLT to study L 98-59. “Without the precision and stability provided by ESPRESSO this measurement would have not been possible,” says Zapatero Osorio. “This is a step forward in our ability to measure the masses of the smallest planets beyond the Solar System.”

Artist’s impression of L 98-59c

The astronomers first spotted three of L 98-59’s planets in 2019, using NASA’s Transiting Exoplanet Survey Satellite (TESS). This satellite relies on a technique called the transit method — where the dip in the light coming from the star caused by a planet passing in front of it is used to infer the properties of the planet — to find the planets and measure their sizes. However, it was only with the addition of radial velocity measurements made with ESPRESSO and its predecessor, the High Accuracy Radial velocity Planet Searcher (HARPS) at the ESO La Silla 3.6-metre telescope, that Demangeon and his team were able to find extra planets and measure the masses and radii of the first three. “If we want to know what a planet is made of, the minimum that we need is its mass and its radius,” Demangeon explains.

Artist’s impression of L 98-59d

The team hopes to continue to study the system with the forthcoming NASA/ESA/CSA James Webb Space Telescope (JWST), while ESO’s Extremely Large Telescope (ELT), under construction in the Chilean Atacama Desert and set to start observations in 2027, will also be ideal for studying these planets. “The HIRES instrument on the ELT may have the power to study the atmospheres of some of the planets in the L 98-59 system, thus complementing the JWST from the ground,” says Zapatero Osorio.

A “fly-to” the L 98-59 planetary system

“This system announces what is to come,” adds Demangeon. “We, as a society, have been chasing terrestrial planets since the birth of astronomy and now we are finally getting closer and closer to the detection of a terrestrial planet in the habitable zone of its star, of which we could study the atmosphere.”

More information

This research was presented in a paper entitled “A warm terrestrial planet with half the mass of Venus transiting a nearby star” to appear in Astronomy & Astrophysics (doi: 10.1051/0004-6361/202140728). https://www.aanda.org/10.1051/0004-6361/202140728

The team is composed of Olivier D. S. Demangeon (Instituto de Astrofísica e Ciências do Espaço, Universidade do Porto, Portugal [IA/UPorto], Centro de Astrofísica da Universidade do Porto, Portugal [CAUP] and Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, Portugal [FCUP]), M. R. Zapatero Osorio (Centro de Astrobiología, Madrid, Spain [CSIC-INTA]), Y. Alibert (Physics Institute, University of Bern, Switzerland [Bern]), S. C. C. Barros (IA/UPorto, CAUP and FCUP), V. Adibekyan (IA/UPorto, CAUP and FCUP), H. M. Tabernero (IA/UPorto and CAUP), A. Antoniadis-Karnavas (IA/UPorto & FCUP), J. D. Camacho (IA/UPorto & FCUP), A. Suárez Mascareño (Instituto de Astrofísica de Canarias, Tenerife, Spain [IAC] and Departamento de Astrofísica, Universidad de La Laguna, Tenerife, Spain [ULL]), M. Oshagh (IAC/ULL), G. Micela (INAF – Osservatorio Astronomico di Palermo, Palermo, Italy), S. G. Sousa (IA/UPortol & CAUP), C. Lovis (Observatoire de Genève, Université de Genève, Geneva, Switzerland [UNIGE]), F. A. Pepe (UNIGE), R. Rebolo (IAC/ULL & Consejo Superior de Investigaciones Científicas, Spain), S. Cristiani (INAF – Osservatorio Astronomico di Trieste, Italy [INAF Trieste]), N. C. Santos (IA/UPorto, CAUP and FCUP), R. Allart (Department of Physics and Institute for Research on Exoplanets, Université de Montréal, Canada and UNIGE), C. Allende Prieto (IAC/ULL), D. Bossini (IA/UPorto), F. Bouchy (UNIGE), A. Cabral (Instituto de Astrofísica e Ciências do Espaço, Faculdade de Ciências da Universidade de Lisboa, Portugal [IA/FCUL] and Departamento de Física da Faculdade de Ciências da Universidade de Lisboa, Portugal), M. Damasso (INAF – Osservatorio Astrofisico di Torino, Italy [INAF Torino]), P. Di Marcantonio (INAF Trieste), V. D’Odorico (INAF Trieste & Institute for Fundamental Physics of the Universe, Trieste, Italy [IFPU]), D. Ehrenreich (UNIGE), J. Faria (IA/UPorto, CAUP and FCUP), P. Figueira (European Southern Observatory, Santiago de Chile, Chile [ESO-Chile] and IA/UPorto), R. Génova Santos (IAC/ULL), J. Haldemann (Bern), J. I. González Hernández (IAC/ULL), B. Lavie (UNIGE), J. Lillo-Box (CSIC-INTA), G. Lo Curto (European Southern Observatory, Garching bei München, Germany [ESO]), C. J. A. P. Martins (IA/UPorto and CAUP), D. Mégevand (UNIGE), A. Mehner (ESO-Chile), P. Molaro (INAF Trieste and IFPU), N. J. Nunes (IA/FCUL), E. Pallé (IAC/ULL), L. Pasquini (ESO), E. Poretti (Fundación G. Galilei – INAF Telescopio Nazionale Galileo, La Palma, Spain and INAF – Osservatorio Astronomico di Brera, Italy), A. Sozzetti (INAF Torino), and S. Udry (UNIGE).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It has 16 Member States: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Ireland, 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. Also at Paranal ESO will host and operate the Cherenkov Telescope Array South, the world’s largest and most sensitive gamma-ray observatory. 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: https://www.eso.org/public/archives/releases/sciencepapers/eso2112/eso2112a.pdf

Photos of the VLT: http://www.eso.org/public/images/archive/category/paranal/

For journalists: subscribe to receive our releases under embargo in your language: https://www.eso.org/public/outreach/pressmedia/#epodpress_form

For cientists: got a story? Pitch your research: http://eso.org/sci/publications/announcements/sciann17369.html

ESO’s Extremely Large Telescope (ELT): https://elt.eso.org/

A neighbouring planetary system reveals its secrets (ESOcast 242 Light): https://www.eso.org/public/videos/eso2112a/

Text Credits: ESO/Bárbara Ferreira/Astronomer at ESO and Instituto de Astrofísica e Ciências do Espaço, instrument scientist of ESPRESSO/Pedro Figueira/INAF – Osservatorio Astrofisico di Torino/Mario Damasso/Instituto de Astrofísica de Canarias/Alejandro Suárez Mascareño/Member of the “Transiting planets” working group of the ESPRESSO science team at Université de Genève/François Bouchy/Instituto de Astrofisica e Ciências do Espaço, Faculdade de Ciências, Universidade do Porto/Nuno Santos/Olivier Demangeon/Chair of the “Atmospheric Characterisation” working group of the ESPRESSO science team at Centro de Astrobiología (CSIC-INTA)/María Rosa Zapatero Osorio/Images Credits: ESO/M. Kornmesser/ESO/L. Calçada/M. Kornmesser (Acknowledgment: O. Demangeon)/Videos Credits: ESO/M. Kornmesser/ESO/L.Calçada/G. Hüdepohl (atacamaphoto.com)/spaceengine.org.

Best regards, Orbiter.ch