Orbiter.ch Space News

mercredi 31 juillet 2019

A satellite to measure light pollution

NOAA & NASA - Suomi NPP Mission patch.

July 31, 2019

An ETH Zurich researcher came up with the idea of analyzing data from an American satellite to determine nocturnal light pollution in Switzerland.

Suomi NPP satellite. Image Credits: NOAA / NASA

Analyzing the data of an American satellite to determine nocturnal light pollution in Switzerland: this is the idea of a Swiss researcher. The result is a map that compares with previous years.

Every morning early, the Suomi NPP (Suomi National Polar-Orbiting Partnership) dedicated to environmental monitoring measures light sources around the world. This US satellite meticulously carries out its tasks day after day since April 2012. NOAA, the US ocean and atmospheric observation agency, collects this data "to monitor and understand the dynamics of our planet," according to its website.

Member of Dark-Sky Switzerland

A biochemist who graduated from the ETH Zurich and is a member of the organization Dark-Sky Switzerland, which campaigns against nocturnal light pollution, Lukas Schuler came up with the idea of creating a map based on these surveys.

Light pollution in Switzerland last year. (Photo: Darksky.ch)

His work, published in the journal Environmental Science & Policy, allows to visualize the night light load in all Switzerland, according to a scale of colors. Comparisons with previous years are possible, as well as trend analysis, according to a statement from Dark-Sky Switzerland published Wednesday.

Shipyards and tourism

Significant increases in luminous intensity are therefore attributable in most cases to large construction sites and new infrastructure, as well as to winter tourism. The decreases are due to the switch to LEDs with anti-scattering protection and better lighting strategies.

This progress is important in light of the growing light pollution and its impact on the fauna and flora. In particular, it is suspected of contributing to the disappearance of pollinating nocturnal insects, without forgetting its disturbing potential for humans.

The authors have examined various aspects of this problem, for example possible links between a decrease in light intensity and criminal acts or road accidents. They found no correlation.

They also analyzed the habitats of crayfish populations in the canton of Zurich. Result: these crustaceans clearly prefer dark areas, corresponding to a maximum brightness of 4.5 full moons, according to a measurement unit developed by the researchers.

Related links:

Dark-Sky Switzerland: https://www.darksky.ch/dss/fr/

Article Dark-Sky Switzerland: https://www.darksky.ch/dss/fr/2019/07/la-suisse-est-anormalement-lumineuse-la-nuit/

EPFZ (ETH Zürich): https://ethz.ch/en.html

NOAA & NASA Suomi NPP: https://www.nasa.gov/mission_pages/NPP/main/index.html
and https://www.nesdis.noaa.gov/tags/suomi-npp

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

Greetings, Orbiter.ch

mardi 30 juillet 2019

NASA Announces Call for Next Phase of Commercial Lunar Payload Services

NASA logo.

July 30, 2019

NASA has announced the latest opportunity for industry to participate in its Commercial Lunar Payload Services (CLPS) efforts to deliver science and technology payloads to and near the Moon.

Image above: Commercial landers will carry NASA-provided science and technology payloads to the lunar surface, paving the way for NASA astronauts to land on the Moon by 2024. Image Credit: NASA.

The newest announcement calls for companies to push the boundaries of current technology to support the next generation of lunar landers that can land heavier payloads on the surface of the Moon, including the South Pole, as part of the agency’s Artemis program, which will send the first woman and next man to the Moon by 2024, setting the stage for future human exploration of Mars.

NASA anticipates the need for both small and mid-size lunar landers to enable a variety of science investigations and larger technology demonstration payloads that will meet science objectives and human exploration goals. Future payloads could include rovers, power sources, science experiments, and technology to be infused into the Artemis program.

“Our commercial partners are helping us to advance lunar science in an unprecedented way,” said Thomas Zurbuchen, NASA’s associate administrator for the agency’s Science Mission Directorate. “As we enable broader opportunities for commercial providers through CLPS, we’re enlarging our capabilities to do novel measurements and technology development scientists have long wanted to do at the Moon.”

Any companies newly selected under this call will join the nine CLPS providers already contracted to provide services to the lunar surface to support NASA exploration priorities and use the Moon as a proving ground for systems and technologies that will enable humans to explore Mars. The CLPS project focuses on a speedy return to the Moon and advances scientific and technical goals on many fronts, with selected companies able to compete for delivery task orders.

“The Artemis program integrates our science and human exploration goals, and we are using our commercial partners to help meet those goals with an innovative and cost-effective approach,” said Steven Clarke, NASA deputy associate administrator for exploration in science. “The capability to land heavier payloads on the lunar surface is a service that NASA has a keen interest in. We’re looking forward to innovative proposals and possibly more partners to advance what we’ve already started with CLPS.”

The CLPS contracts are indefinite delivery, indefinite quantity contracts with a combined maximum contract value of $2.6 billion with performance through 2028.

Related article:

NASA Selects 12 New Lunar Science, Technology Investigations
https://orbiterchspacenews.blogspot.com/2019/07/nasa-selects-12-new-lunar-science.html

Related links:

Artemis: https://www.nasa.gov/artemis

Commercial Space: http://www.nasa.gov/exploration/commercial/index.html

Moon to Mars: https://www.nasa.gov/topics/moon-to-mars/

For more information about Commercial Lunar Payload Services, visit:

https://www.nasa.gov/clps and https://procurement.jsc.nasa.gov/clps

Image (mentioned), Text, Credits: NASA/Sean Potter/Grey Hautaluoma/JSC/Jenny Knotts.

Greetings, Orbiter.ch

NASA Announces US Industry Partnerships to Advance Moon, Mars Technology

NASA logo.

July 30, 2019

As NASA prepares to land humans on the Moon by 2024 with the Artemis program, commercial companies are developing new technologies, working toward space ventures of their own, and looking to NASA for assistance. NASA has selected 12 U.S. companies for 19 partnerships to mature industry-developed space technologies and help maintain American leadership in space.

NASA centers will partner with the companies, which range from small businesses with fewer than a dozen employees to large aerospace organizations, to provide expertise, facilities, hardware and software at no cost. The partnerships will advance the commercial space sector and help bring new capabilities to market that could benefit future NASA missions.

Image above: Illustration of a human landing system and crew on the lunar surface with Earth near the horizon. Image Credit: NASA.

“NASA’s proven experience and unique facilities are helping commercial companies mature their technologies at a competitive pace,” said Jim Reuter, associate administrator of NASA’s Space Technology Mission Directorate (STMD). “We’ve identified technology areas NASA needs for future missions, and these public-private partnerships will accelerate their development so we can implement them faster.”

The selections were made through NASA’s Announcement of Collaboration Opportunity (ACO) released in October 2018. They will result in non-reimbursable Space Act Agreements between the companies and NASA. The selections cover the following technology focus areas, which are important to America’s Moon to Mars exploration approach.

Advanced Communications, Navigation and Avionics

- Advanced Space of Boulder, Colorado, will partner with NASA’s Goddard Space Flight Center in Greenbelt, Maryland, to advance lunar navigation technologies. The collaboration will help mature a navigation system between Earth and the Moon that could supplement NASA’s Deep Space Network and support future exploration missions.

- Vulcan Wireless of Carlsbad, California, also will partner with Goddard to test a CubeSat radio transponder and its compatibility with NASA’s Space Network.

Advanced Materials

- Aerogel Technologies of Boston will work with NASA’s Glenn Research Center in Cleveland to improve properties of flexible aerogels for rocket fairings and other aerospace applications. The material can result in 25% weight savings over soundproofing materials currently used in rocket fairings.

- Lockheed Martin of Littleton, Colorado, will work with NASA’s Langley Research Center in Hampton, Virginia, to test materials made from metal powders using solid-state processing to improve the design of spacecraft that operate in high-temperature environments.

- Spirit AeroSystem Inc. of Wichita, Kansas, will partner with NASA’s Marshall Space Flight Center in Huntsville, Alabama, to improve the durability of low-cost reusable rockets manufactured using friction stir welding. This welding method, already being used for NASA’s Space Launch System, results in a stronger, more defect-free seal compared to traditional methods of joining materials with welding torches.

Entry, Decent and Landing

- Anasphere of Bozeman, Montana, will partner with Marshall to test a compact hydrogen generator for inflating heat shields, which could help deliver larger payloads to Mars.

- Bally Ribbon Mills of Bally, Pennsylvania, will perform thermal testing in the Arc Jet Complex at NASA’s Ames Research Center in California’s Silicon Valley. The facility will be used to test a new seamless weave for a mechanically deployable carbon fabric heat shield.

- Blue Origin of Kent, Washington, will collaborate with NASA’s Johnson Space Center in Houston and Goddard to mature a navigation and guidance system for safe and precise landing at a range of locations on the Moon.

- Sierra Nevada Corporation of Sparks, Nevada, will work with NASA on two entry, decent and landing projects. The company will partner with Langley to capture infrared images of their Dream Chaser spacecraft as it re-enters Earth’s atmosphere traveling faster than the speed of sound.

- For the second collaboration, Sierra Nevada Corporation and Langley will mature a method to recover the upper stage of a rocket using a deployable decelerator.

- SpaceX of Hawthorne, California, will work with NASA’s Kennedy Space Center in Florida to advance their technology to vertically land large rockets on the Moon. This includes advancing models to assess engine plume interaction with lunar regolith.

In-Space Manufacturing and Assembly

- Maxar Technologies of Palo Alto, California, will work with Langley to build a breadboard – a base for prototyping electronics – for a deployable, semi-rigid radio antenna. In-orbit assembly of large structures like antennae will enhance the performance of assets in space. Such capabilities could enable entirely new exploration missions that are currently size-constrained and reduce launch costs due to improved packaging.

Power

- Blue Origin will partner with Glenn and Johnson to mature a fuel cell power system for the company’s Blue Moon lander. The system could provide uninterrupted power during the lunar night, which lasts for about two weeks in most locations.

- Maxar will test lightweight solar cells for flexible solar panels using facilities at Glenn and Marshall that mimic the environment of space. The technology could be used by future spacecraft to provide more power with a lower mass system.

Propulsion

- Aerojet Rocketdyne of Canoga Park, California, and Marshall will design and manufacture a lightweight rocket engine combustion chamber using innovative processes and materials. The goal of the project is to reduce manufacturing costs and make the chamber scalable for different missions.

- Blue Origin, Marshall and Langley will evaluate and mature high-temperature materials for liquid rocket engine nozzles that could be used on lunar landers.

- Colorado Power Electronics Inc. of Fort Collins, Colorado, will partner with Glenn to mature power processing unit technology that extends the operating range of Hall thrusters, which are primarily used on Earth-orbiting satellites and can also be used for deep space missions. By integrating their technology with NASA and commercial Hall thrusters, the company expects to provide a propulsion system that can significantly increase mission payload or extend mission durations.

- SpaceX will work with Glenn and Marshall to advance technology needed to transfer propellant in orbit, an important step in the development of the company’s Starship space vehicle.

Other Exploration Technologies

- Lockheed Martin will partner with Kennedy to test technologies and operations for autonomous in-space plant growth systems. Integrating robotics with plant systems could help NASA harvest plants on future platforms in deep space.

Through ACO, NASA helps reduce the development cost of technologies and accelerate the infusion of emerging commercial capabilities into space missions. As the agency embarks on its next era of exploration, STMD is focused on advancing technologies and testing new capabilities for use at the Moon that also will be critical for crewed missions to Mars.

Related links:

Artemis: https://www.nasa.gov/artemis/

Announcement of Collaboration Opportunity (ACO): https://nspires.nasaprs.com/external/solicitations/summary!init.do?solId=%7b60A4A72B-CAD1-69B7-1B23-3D7D7A7585AF%7d&path=open

Moon to Mars: https://www.nasa.gov/topics/moon-to-mars

Deep Space Network: https://www.nasa.gov/directorates/heo/scan/services/networks/dsn

Space Network: https://www.nasa.gov/directorates/heo/scan/services/networks/sn

Flexible aerogels: https://www.nasa.gov/topics/technology/features/aerogels.html

Space Launch System (SLS): https://blogs.nasa.gov/Rocketology/tag/friction-stir-welding/

Arc Jet Complex: https://www.nasa.gov/centers/ames/thermophysics-facilities/arcjet-complex

Hall thrusters: https://www.nasa.gov/image-feature/nasa-glenns-hall-thruster

Commercial Space: http://www.nasa.gov/exploration/commercial/index.html

For more information about NASA’s Space Technology Mission Directorate, visit: https://www.nasa.gov/spacetech

For more information about Space Technology Mission Directorate opportunities, visit: https://www.nasa.gov/directorates/spacetech/solicitations

Image (mentioned), Text, Credits: NASA/Sean Potter/Clare Skelly.

Greetings, Orbiter.ch

New Space Research Kicks Off Ahead of Wednesday Cargo Launch

ISS - Expedition 60 Mission patch.

July 30, 2019

Microgravity research is ramping up aboard the International Space Station with brand new science payloads and an expanded Expedition 60 crew. July will see one more mission going up to the orbiting lab as a Russian cargo craft counts down to a Wednesday launch and docking.

The Cell Science-02 experiment is underway on the station to explore bone-healing therapies. Astronauts Nick Hague and Luca Parmitano activated the Life Sciences Glovebox this morning to conduct the new bone research. Hague then retrieved bone cell samples to observe healing and tissue regeneration properties to promote human health on Earth and in space.

Image above: NASA astronauts Christina Koch and Andrew Morgan are pictured working inside the Unity module which connects the International Space Station’s U.S. segment with the Russian segment. Image Credit: NASA.

Parmitano then photographed samples inside the Kubik incubator for the new Biorock space-mining study. Harnessing the power of microbes could help future astronauts extract precious minerals from the surface of the Moon and Mars.

NASA astronauts Christina Koch and Andrew Morgan completed setting up habitats housing mice shipped aboard the SpaceX Dragon space freighter. Scientists are comparing the space rodents to a sample of mice back on Earth to understand biological changes caused by microgravity.

International Space Station (ISS). Image Credit: NASA

Russia’s Progress 73 (73P) cargo craft is standing at its launch pad in Kazakhstan counting down to a liftoff Wednesday at 8:10 a.m. EDT. It will take a three-and-a-half-hour trip to the station’s Pirs Docking Compartment carrying almost three tons of food, fuel and supplies for the crew. NASA TV is broadcasting the fast-track launch and docking activities live starting at 7:45 a.m.

Cosmonauts Alexey Ovchinin and Alexander Skvortsov will be monitoring the 73P’s automated approach and rendezvous Wednesday. Today, the veteran station residents split their time between human research, computer maintenance and hardware inspections.

Viewing the Mediterranean Coasts of Tunisia and Libya from the Space Station

Cyanide Compounds Discovered in Meteorites May Hold Clues to the Origin of Life

NASA - OSIRIS-REx Mission logo.

July 30, 2019

Cyanide and carbon monoxide are both deadly poisons to humans, but compounds containing iron, cyanide, and carbon monoxide discovered in carbon-rich meteorites by a team of scientists at Boise State University and NASA may have helped power life on early Earth. The extraterrestrial compounds found in meteorites resemble the active site of hydrogenases, which are enzymes that provide energy to bacteria and archaea by breaking down hydrogen gas (H₂). Their results suggest that these compounds were also present on early Earth, before life began, during a period of time when Earth was constantly bombarded by meteorites and the atmosphere was likely more hydrogen-rich.

Image above: Artist’s concept of meteors impacting ancient Earth. Some scientists think such impacts may have delivered water and other molecules useful to emerging life on Earth. Image Credits: NASA's Goddard Space Flight Center Conceptual Image Lab.

“When most people think of cyanide, they think of spy movies – a guy swallowing a pill, foaming at the mouth and dying, but cyanide was probably an essential compound for building molecules necessary for life,” explained Dr. Karen Smith, senior research scientist at Boise State University, Boise, Idaho. Cyanide, a carbon atom bound to a nitrogen atom, is thought to be crucial for the origin of life, as it is involved in the non-biological synthesis of organic compounds like amino acids and nucleobases, which are the building blocks of proteins and nucleic acids used by all known forms of life.

Smith is lead author of a paper on this research published June 25 in Nature Communications. Smith, along with Boise State assistant professor Mike Callahan, a co-author on the paper, developed new analytical methods to extract and measure ancient traces of cyanide in meteorites. They found that the meteorites containing cyanide belong to a group of carbon-rich meteorites called CM chondrites. Other types of meteorites tested, including a Martian meteorite, contained no cyanide.

“Data collected by NASA’s OSIRIS-REx spacecraft of asteroid Bennu indicate that it is related to CM chondrites,” said co-author Jason Dworkin of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “OSIRIS-REx will deliver a sample from Bennu to study on Earth in 2023. We will search for these very compounds to try to connect Bennu to known meteorites and to understand the potential delivery of prebiotic compounds such as cyanide, which may have helped start life on the early Earth or other bodies in the solar system.”

Cyanide has been found in meteorites before. However, in the new work, Smith and Callahan were surprised to discover that cyanide, along with carbon monoxide (CO), were binding with iron to form stable compounds in the meteorites. They identified two different iron cyano-carbonyl complexes in the meteorites using high-resolution liquid chromatography-mass spectrometry. “One of the most interesting observations from our study is that these iron cyano-carbonyl complexes resemble portions of the active sites of hydrogenases, which have a very distinct structure,” Callahan said.

Graphic above: Meteorites contain metal-organic compounds that resemble portions of enzymes found in bacteria and archaea. CN is cyanide, CO is carbon monoxide, Fe is iron, Ni is nickel. Graphic Credits: Smith et al. Nature Communications, 2019.

Hydrogenases are present in almost all modern bacteria and archaea and are widely believed to be ancient in origin. Hydrogenases are large proteins, but the active site – the region where chemical reactions take place – happens to be a much smaller metal-organic compound contained within the protein, according to Callahan. It is this compound that resembles the cyanide-bearing compounds the team discovered in meteorites.

An enduring mystery regarding the origin of life is how biology could have arisen from non-biological chemical processes. The similarities between the active sites in hydrogenase enzymes and the cyanide compounds the team found in meteorites suggests that non-biological processes in the parent asteroids of meteorites and on ancient Earth could have made molecules useful to emerging life.

“Cyanide and carbon monoxide attached to a metal are unusual and rare in enzymes. Hydrogenases are the exception. When you compare the structure of these iron cyano-carbonyl complexes in meteorites to these active sites in hydrogenases, it makes you wonder if there was a link between the two,” Smith added. “It’s possible that iron cyano-carbonyl complexes may have been a precursor to these active sites and later incorporated into proteins billions of years ago. These complexes probably acted as sources of cyanide on early Earth as well.”

Artist's view of OSIRIS-REx spacecraft. Image Credit: NASA

The research was funded by the NASA Emerging Worlds Program, NASA Astrobiology Institute, and the NASA Earth and Space Science Fellowship. The team included Smith, Callahan, and colleagues at Penn State University, University of Maryland and the NASA Goddard Space Flight Center. NASA Goddard provides overall mission management, systems engineering and safety and mission assurance for OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer). Dante Lauretta is the mission's principal investigator at the University of Arizona. Lockheed Martin Space Systems in Denver is building the spacecraft. OSIRIS-REx is the third mission in NASA's New Frontiers Program. NASA's Marshall Space Flight Center in Huntsville, Alabama, manages New Frontiers for the agency's Science Mission Directorate in Washington. NASA is exploring our Solar System and beyond, uncovering worlds, stars, and cosmic mysteries near and far with our powerful fleet of space and ground-based missions.

Related links:

Nature Communications: https://www.nature.com/articles/s41467-019-10866-x

Asteroids: https://www.nasa.gov/mission_pages/asteroids/main/index.html

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

OSIRIS-REx (Origins Spectral Interpretation Resource Identification Security Regolith Explorer): http://www.nasa.gov/mission_pages/osiris-rex/index.html

Boise State University: https://chemistry.boisestate.edu/

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

Images (mentioned), Graphic (mentioned), Text, Credits: NASA/GSFC/Bill Steigerwald/Nancy Jones/Boise State University/Cienna Madrid.

Greetings, Orbiter.ch

lundi 29 juillet 2019

Crew Unloads Dragon as Russian Cargo Ships Depart, Prep for Launch

ISS - Expedition 60 Mission patch.

July 29, 2019

A new U.S. space freighter is open for business today after delivering its payload to the International Space Station on Saturday. Meanwhile, a Russian resupply rocket is processing for another space delivery mission on Wednesday that will take less than three and a half hours after launch.

NASA Flight Engineer Nick Hague opened Dragon’s hatch early Sunday beginning a month of cargo operations. His fellow crewmates Christina Koch and Andrew Morgan are unloading critical research samples and stowing them inside the station’s science freezers and incubators for analysis.

Image above: Russia’s Progress 73 cargo craft stands at its launch pad at the Baikonur Cosmodrome in Kazakhstan counting down to a Wednesday liftoff. Image Credit: Roscosmos.

The new experiments will be exploring microgravity’s effect on a variety of biological and physical processes benefitting humans on Earth and in space. The crew will be researching 3-D bio-printing, silica manufacturing, botany and tissue regeneration and a host of other space phenomena.

Progress MS-12 ready for launch

Robotics controllers will remove the International Docking Adapter-3 (IDA-3), a new commercial crew ship docking port, from Dragon’s unpressurized trunk in mid-August. A pair of spacewalkers will install the IDA-3 on the Harmony module’s space-facing Pressurized Mating Adapter a few days later.

Russia’s Pirs Docking Compartment port opened up today at 6:44 a.m. EDT when the Progress 72 (72P) cargo craft undocked completing a four-month stay at the orbiting lab. It will re-enter the Earth’s atmosphere loaded with trash and discarded gear for a fiery, but safe disposal over the Pacific Ocean.

International Space Station (ISS). Animation Credit: NASA

The new Progress 73 cargo ship will replace 72P after it launches Wednesday at 8:10 a.m. from the Baikonur Cosmodrome in Kazakhstan. It will dock to Pirs that same morning at 11:35 a.m. after just two Earth orbits packed with more food, fuel and supplies for the crew.

Cosmonauts Alexey Ovchinin and Alexander Skvortsov are training today on the tele-robotically operated rendezvous unit (TORU) for Wednesday’s arrival of the 73P. The duo will be in the Zvezda service module at the controls of the TORU monitoring the 73P’s approach ready to take over manual docking operations in the unlikely event of an emergency.

Related links:

Expedition 60: https://www.nasa.gov/mission_pages/station/expeditions/expedition60/index.html

3-D bio-printing: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=7599

Silica manufacturing: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7716

Botany: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7892

Tissue regeneration: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=1676

International Docking Adapter-3 (IDA-3): https://www.nasa.gov/feature/meet-the-international-docking-adapter

Harmony module: https://www.nasa.gov/mission_pages/station/structure/elements/harmony

Pirs Docking Compartment: https://www.nasa.gov/mission_pages/station/structure/elements/pirs-docking-compartment

Zvezda service module: https://www.nasa.gov/mission_pages/station/structure/elements/zvezda-service-module.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

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

Best regards, Orbiter.ch

NASA’s TESS Mission Scores ‘Hat Trick’ With 3 New Worlds

NASA - Transiting Exoplanet Survey Satellite (TESS) logo.

July 29, 2019

NASA’s newest planet hunter, the Transiting Exoplanet Survey Satellite (TESS), has discovered three new worlds — one slightly larger than Earth and two of a type not found in our solar system — orbiting a nearby star. The planets straddle an observed gap in the sizes of known planets and promise to be among the most curious targets for future studies.

TESS Object of Interest (TOI) 270 is a faint, cool star more commonly identified by its catalog name: UCAC4 191-004642. The M-type dwarf star is about 40% smaller than the Sun in both size and mass, and it has a surface temperature about one-third cooler than the Sun’s. The planetary system lies about 73 light-years away in the southern constellation of Pictor.

Image above: This infographic illustrates key features of the TOI 270 system, located about 73 light-years away in the southern constellation Pictor. The three known planets were discovered by NASA’s Transiting Exoplanet Survey Satellite through periodic dips in starlight caused by each orbiting world. Insets show information about the planets, including their relative sizes, and how they compare to Earth. Temperatures given for TOI 270’s planets are equilibrium temperatures, calculated without the warming effects of any possible atmospheres. Image Credits: NASA’s Goddard Space Flight Center/Scott Wiessinger.

“This system is exactly what TESS was designed to find — small, temperate planets that pass, or transit, in front of an inactive host star, one lacking excessive stellar activity, such as flares,” said lead researcher Maximilian Günther, a Torres Postdoctoral Fellow at the Massachusetts Institute of Technology’s (MIT) Kavli Institute for Astrophysics and Space Research in Cambridge. “This star is quiet and very close to us, and therefore much brighter than the host stars of comparable systems. With extended follow-up observations, we’ll soon be able to determine the make-up of these worlds, establish if atmospheres are present and what gases they contain, and more.”

A paper describing the system was published in the journal Nature Astronomy and is now available online.

The innermost planet, TOI 270 b, is likely a rocky world about 25% larger than Earth. It orbits the star every 3.4 days at a distance about 13 times closer than Mercury orbits the Sun. Based on statistical studies of known exoplanets of similar size, the science team estimates TOI 270 b has a mass around 1.9 times greater than Earth’s.

Animation above: Compare and contrast worlds in the TOI 270 system with these illustrations of each planet. Temperatures given for TOI 270 planets are equilibrium temperatures, calculated without taking into account the warming effects of any possible atmospheres. Animation Credits: NASA’s Goddard Space Flight Center.

All of the planets are expected to be tidally locked to the star, which means they only rotate once every orbit and keep the same side facing the star at all times, just as the Moon does in its orbit around Earth.

Planet c and d might best be described as mini-Neptunes, a type of planet not seen in our own solar system. The researchers hope further exploration of TOI 270 may help explain how two of these mini-Neptunes formed alongside a nearly Earth-size world.

Transiting Exoplanet Survey Satellite or TESS. Image Credit: NASA

“An interesting aspect of this system is that its planets straddle a well-established gap in known planetary sizes,” said co-author Fran Pozuelos, a postdoctoral researcher at the University of Liège in Belgium. “It is uncommon for planets to have sizes between 1.5 and two times that of Earth for reasons likely related to the way planets form, but this is still a highly controversial topic. TOI 270 is an excellent laboratory for studying the margins of this gap and will help us better understand how planetary systems form and evolve.”

Günther’s team is particularly interested in the outermost planet, TOI 270 d. The team estimates the planet’s equilibrium temperature to be about 150 degrees Fahrenheit (66 degrees C). This makes it the most temperate world in the system — and as such, a rarity among known transiting planets.

"TOI 270 is perfectly situated in the sky for studying the atmospheres of its outer planets with NASA's future James Webb Space Telescope," said co-author Adina Feinstein, a doctoral student at the University of Chicago. "It will be observable by Webb for over half a year, which could allow for really interesting comparison studies between the atmospheres of TOI 270 c and d."

(Click on the image for enlarge)

Image above: The TOI 270 system is so compact that the orbits of Jupiter and its moons in our own solar system offer the closest reasonable comparison, as illustrated here. Image Credits: NASA’s Goddard Space Flight Center.

The team hopes further research may reveal additional planets beyond the three now known. If planet d has a rocky core covered by a thick atmosphere, its surface would be too warm for the presence of liquid water, considered a key requirement for a potentially habitable world. But follow-up studies may discover additional rocky planets at slightly greater distances from the star, where cooler temperatures could allow liquid water to pool on their surfaces.

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 Harvard-Smithsonian Center for Astrophysics 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:

Nature Astronomy: https://www.nature.com/articles/s41550-019-0845-5

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

Images (mentioned), Animation (mentioned), Text, Credits: NASA/Rob Garner/Goddard Space Flight Center, by Francis Reddy.

Greetings, Orbiter.ch