NASA's exoplanet hunter TESS spots a record-breaking 3-star system

Using NASA's exoplanet-hunting spacecraft, the Transiting Exoplanet Survey Satellite (TESS), scientists have spotted a record-breaking triple-star system so tightly bound that it could fit comfortably between the sun and its closest planet, Mercury. The system, designated TIC 290061484 contains twin stars that race around each other once every 1.8 Earth days as well as a third star that orbits this pair once every 25 Earth days. This triple star system's super-tight orbit, located just under 5,000 light-years away in the constellation Cygnus, the swan, makes it a record-breaker. The previous record-holder for the tightest three-star system orbit is Lamba Tauri, which set the record in 1956 with its third star taking 33 days to orbit its inner twin stars. The discovery team included citizen scientists who met as part of the now-closed Planet Hunters project, which ran from 2010 to 2013. The amateurs joined with professional astronomers to form the Visual Survey Group collaboration, which has been operating for a decade. "Thanks to the compact, edge-on configuration of the system, we can measure the orbits, masses, sizes and temperatures of its stars," team member Veselin Kostov from NASA's Goddard Space Flight Center and part of the SETI Institute said in a statement. "We can study how the system formed and predict how it may evolve."

Three's company

The team thinks the star system TIC 290061484 is highly stable because the stars orbit each other in nearly the same plane. If the stars' orbits were tilted in different directions, their gravitational influences would disrupt their orbits, making the system unstable.

This stability won't last forever, though — maybe a few million years. Though that's a long time to us, it's a blink of an eye in our 13.8 billion-year-old cosmos. And as Visual Survey Group team member Saul Rappaport, a physics professor at the Massachusetts Institute of Technology (MIT), reminds us, referring to the fate of the TIC 290061484 stars: "No one lives here."

As the twin stars at the heart of this triple star system age, they will expand outward and ultimately merge. This will trigger a massive supernova explosion in around 20 to 40 million years. Fortunately, this is unlikely to impact any life on planets around the three stars as there don't seem to be any planets close enough to the stars to support life (as we know it, at least).

"We think the stars formed together from the same growth process, which would have disrupted planets from forming very closely around any of the stars," Rappaport said.

It is possible, however, that a very distant planet could exist in the TIC 290061484 system, orbiting the three stars as if they were one.

The Roman Telescope's promise

The team spotted the record-breaking triple star system because of strobing starlight caused by the stars crossing in front of each other, as seen from our position on Earth.

The team turned to machine learning to analyze vast amounts of data from TESS to spot a pattern indicating these eclipses. They then called upon the aid of citizen scientists to further filter this data to spot interesting signals.

"We're mainly looking for signatures of compact multi-star systems, unusual pulsating stars in binary systems, and weird objects," Rappaport said. "It's exciting to identify a system like this because they're rarely found, but they may be more common than current tallies suggest."

The team thinks many more systems like this are likely to be spread across the Milky Way, waiting to be discovered. Some may even exhibit shorter orbits than the stars of the TIC 290061484 system. Current technology may be insufficient to spot these tightly bound triple stars, but help is on the way.

Set to launch no earlier than May 2027, the Nancy Grace Roman Space Telescope, or just "Roman," will provide vastly more detailed images of space than those gathered by TESS.

An illustration of the upcoming Nancy Grace Roman Space Telescope. (Image credit: NASA)

NASA's exoplanet hunter takes a wide view of the cosmos, while Roman will take a "zoomed-in" view. To put this into perspective, an area of space that is covered by a single pixel in an image from TESS will have a whopping 36,000 pixels in an image from Roman. This will, in fact, allow Roman to gaze deep into the heart of the Milky Way, where stars are tightly packed together.

"We don't know much about a lot of the stars in the center of the galaxy except for the brightest ones," team member and Goddard data scientist Brian Powell said. "Roman's high-resolution view will help us measure light from stars that usually blur together, providing the best look yet at the nature of star systems in our galaxy."

One of Roman's main missions will be to monitor the light from hundreds of millions of stars, which should help astronomers spot the strobing effect that revealed the TIC 290061484 system.

"We're curious why we haven't found star systems like these with even shorter outer orbital periods," Powell explained. "Roman should help us find them and bring us closer to figuring out what their limits might be."

Roman may even enable scientists to spot tightly packed star systems with more than three stars, perhaps as many as six, buzzing around each other like bees in a hive.

"Before scientists discovered triply eclipsing triple star systems, we didn't expect them to be out there," team member Tamás Borkovits of the Baja Observatory in Hungary said in the statement. "But once we found them, we thought, well, why not?

"Roman, too, may reveal never-before-seen categories of systems and objects that will surprise astronomers."

James Webb Space Telescope finds 'puffball' exoplanet is uniquely lopsided

Using the James Webb Space Telescope (JWST), astronomers have discovered that a "puffy" planet is asymmetric, meaning there is a significant difference between one side of the atmosphere and the other. The extrasolar planet or "exoplanet" in question is WASP-107 b, which orbits an orange star smaller than the sun located around 210 light-years away. Discovered in 2017, WASP-107 b is 94% the size of Jupiter but only has 10% of the mass of the solar system gas giant. This means it is one of the least dense exoplanets ever discovered, far "puffier" than expected. Earlier this year, scientists determined this is likely the result of the interior of WASP-107 b being much hotter than predicted, and the planet is also thought to possess a rocky core that is larger than what was previously modeled. These strange characteristics were explained by a scarcity of methane in its atmosphere. Now, scientists have another WASP-107 b mystery to solve. The curious asymmetry of WASP-107 b presents astronomers with a conundrum. "This is the first time the east-west asymmetry of any exoplanet has ever been observed from space as it transits its star," Matthew Murphy, a graduate student at the University of Arizona's Steward Observatory, said in a statement. Murphy and colleagues studied WASP-107 by recording light from its host star as it passed through the atmosphere of the planet as it crossed or "transited" the face of its star. "A transit is when a planet passes in front of its star — like the moon does during a solar eclipse," Murphy said, adding that "observations made from space have a lot of different advantages versus observations that are made from the ground."

An illustration of the inflated exoplanet WASP-107 b orbiting its star. (Image credit: NASA, ESA, CSA, Ralf Crawford (STScI))

WASP-107 b is unbalanced

WASP-107 b orbits its star at a distance of around 5 million miles, or about 6% of the distance between Earth and the sun. This means that the planet completes an orbit in around five Earth days. In addition, the exoplanet is tidally locked to its star. This results in one side, the "dayside," permanently facing the star, while the other, the "nightside," faces out to space in perpetuity.

The exoplanet isn't as hot as many worlds so close to their stars. Its temperature is 890 degrees Fahrenheit (477 degrees Celsius), which puts it between the hottest exoplanets and the relatively chilly planets of the solar system. WASP-107 b is uniquely light in terms of density, which gives rise to weak gravity and results in a highly inflated atmosphere.

"We don't have anything like it in our own solar system. It is unique, even among the exoplanet population," Murphy said.

Because elements absorb and emit light at characteristic wavelengths, the spectrum of light passing through an atmosphere can reveal what that atmosphere is made of via a technique called transmission spectroscopy. Because the JWST was able to observe WASP-107 b as it passed in front of its star, scientists were able to determine the composition of its atmosphere.

The transmission spectrum of WASP-107 b showing the composition of its atmosphere. (Image credit: NASA, ESA, CSA, Ralf Crawford (STScI) Science: L. Welbanks (ASU) and the JWST MANATEE team)

The JWST's high precision also allowed the team to get "snapshots" of the exoplanet and separate signals emerging from its east and west sides. This allowed them to better understand the processes happening in the atmosphere of WASP-107 b.

"These snapshots tell us a lot about the gases in the exoplanet's atmosphere, the clouds, the structure of the atmosphere, the chemistry, and how everything changes when receiving different amounts of sunlight," Murphy continued. "Traditionally, our observing techniques don't work as well for these intermediate planets, so there's been a lot of exciting open questions that we can finally start to answer.

"For example, some of our models told us that a planet like WASP-107b shouldn't have this asymmetry at all — so we're already learning something new."

The team now plans to examine the data they collected with the JWST more closely to build a better picture of WASP-107 b and pinpoint what is causing the asymmetry in its atmosphere.

"For almost all exoplanets, we can't even look at them directly, let alone be able to know what's going on one side versus the other," Murphy concluded. "For the first time, we're able to take a much more localized view of what's going on in an exoplanet's atmosphere."

Samara Aerospace claims SpaceWERX contract

Startup Samara Aerospace won a SpaceWERX contract to develop a unique approach to satellite pointing. Under a $1.25 million direct-to-phase two contract awarded in late August, Samara Aerospace will work with an Earth-imaging company to improve pointing accuracy for a 200- to 500-kilogram spacecraft. “This is a huge win for us,” said Patrick Haddox, Samara Aerospace co-founder and CEO. The innovation that prompted aerospace engineers Haddox and Vedant to found Samara Aerospace is called Multifunctional Structures for Attitude Control (MSAC). Vedant patented MSAC with James T. Allison, director of the Engineering System Design Laboratory at the University of Illinois, Urbana-Champaign. NASA’s Jet Propulsion Laboratory supported the technology development, said Vedant, who holds a PhD in aerospace engineering from the University of Illinois. “MSAC allows us to put small piezoelectric actuators in the hinges of deployable solar panels,” Haddox told SpaceNews. “By actuating those very precisely and in rapid succession, we can induce little circular vibrations into the panels. When you vibrate a mass in a circle, you get the same effect as spinning a wheel in a circle.” In fact, rather than inducing jitter, MSAC promises active noise cancellation, Haddox said.

Samara Aerospace is focused on Multifunctional Structures for Attitude Control, technology that includes small piezoelectric actuators in the hinges of deployable solar panels to improve satellite pointing accuracy. Credit: Samara Aerospace

“For any jitter detected at a sensitive payload, we do equal and opposite vibration with the solar panels to make the platform as steady as possible,” Haddox said. As a result, MSAC could improve pointing accuracy for Earth-observation and optical-communications satellites, he added.

“Traditionally, there’s been a fight between guidance, navigation and control engineers, who want satellite maneuverability, and power system engineers, who want large solar panels,” Vedant said. “We literally flip the trade. A larger solar panel comes with its own agility.”
Rapid Scaling

Samara Aerospace, established in 2022, completed the TechStars Los Angeles accelerator earlier this year. And in January, the National Science Foundation announced a $275,000 Small Business Technology Transfer award to Samara Aerospace and the University of Illinois Urbana-Champaign to produce a “flight capable” MSAC demonstrator.

“The result of this Phase 1 award will be a more reliable, efficient, and industry-ready MSAC system, as well as the opportunity for a $1.5M Phase 2 grant from NSF,” Samara Aerospace posted on LinkedIn. “This would allow Samara to launch our spacecraft into orbit, providing critical data and flight heritage.”

Samara Aerospace recently opened an office in San Francisco for its staff, which is expected to double from five to 10 employees by the end of the year.

“We’re scaling rapidly and getting started on creating our first hummingbird technology demonstrator,” Haddox said.

Hummingbird is the name of Samara’s thin spacecraft bus. Thanks to MSAC, “we’re able to build our satellites flat, basically on a plate,” Haddox said.

Canopy wins Air Force contracts to develop thermal protection systems

The U.S. Air Force awarded Canopy Aerospace two contracts with a combined value of $2.8 million to develop thermal protection systems (TPS). One contract focuses on Canopy’s transpiration-cooled TBS. Under a second contract, Canopy will embed high-temperature sensors in the TPS material. Denver-based Canopy was founded in 2021 to develop manufacturing processes that rely on software, automation and 3D-printing to supply heat shields for spacecraft and hypersonic vehicles. “We’ve since expanded our vision significantly to solve thermal management across all industries including space, defense, power generation, power electronics and computer systems,” Matt Shieh, Canopy co-founder and CEO, told SpaceNews. Canopy’s latest contracts were awarded in August through AFWERX in partnership with the Air Force Research Laboratory Space Vehicles Directorate’s Atomic Long-Range Systems Branch. The Air Force Materiel Command’s Arnold Engineering Development Complex is supporting the work. The Air Force contracts “help inform and influence our work with commercial partners,” Shieh said. “We see the government as validating the technology that needs to be developed and the problems that need to be solved in this industry.”

Canopy's high-heat flux testing of thermal protection system materials. Credit: Canopy Aerospace

Transpiration Cooling

Canopy is additively manufacturing ceramic materials for transpiration-cooled TPS under one of the contracts. Hypersonic vehicles can cool themselves by expelling pressurized fluid from the leading edge. The evaporating fluid forms an insulation layer, protecting the vehicle from extreme heating during atmospheric reentry.

Under a second award, Canopy is embedding sensors in the TPS to monitor the environment. The goal is to “extend the design envelope for future systems development and reduce downtime needed for maintenance and inspection of strategic nuclear reentry systems,” according to the Sept. 5 news release.

While the research campaigns are distinct, the technologies – transpiration-cooling and embedded sensors – could be combined in future TPS designs, Will Dickson, Canopy chief commercial officer, said by email.

Canopy is holding a ribbon-cutting ceremony Sept. 5 for its new facility south of Denver. The 6,096-square-meter facility is designed for the company’s manufacturing and materials development activities.

To date, Canopy has won $7.5 million in government contracts and raised $4 million in venture capital.

Why the 7 worlds of TRAPPIST-1 waltz in peculiar patterns

The stability of the TRAPPIST-1 system is the result of a more unstable past. Scientists may have finally revealed the history of the tantalizing TRAPPIST-1 system, an intricate collection of seven worlds that sit about 40 light-years away from us. These worlds, many astronomers and astrobiologists say, may offer us a promising chance of finding life outside the solar system — but they also exhibit peculiar orbital patterns. The newly outlined history of TRAPPIST-1 may, at last, explain how those patterns came to be. When planets form around a young star, their orbital periods often enter "resonances" with each other. An everyday example of a resonance has to do with pushing someone on a playground swing — if you time the push to coincide with the natural frequency of the swing, such as when the swing is just about to go back down, your push would amplify the size of the swing's arc. Similarly, planets often find themselves in resonances with each other. For example, an inner planet can orbit exactly twice for every one orbit of an outer planet. This is a 2:1 resonance, and like pushing a child on a swing amplifies how fast they swing, the exchange of gravitational energy between resonant planets usually makes their orbits unstable, amplifying orbital periods until the planets eventually move out of resonance with one another. Another common planetary resonance is 3:2.

A line-up of the worlds of TRAPPIST-1 are shown in this artist’s impression. (Image credit: NASA/JPL–Caltech)

For the above reason, planetary resonances often become unstable over time, such as in our solar system — but not always. Some planetary systems manage to keep their resonance patterns, and TRAPPIST-1 is one of those systems.

Systems with stable resonances are no doubt aided by how compact the system is; TRAPPIST-1's seven worlds are spread across less than 8 million kilometers, and they would all easily fit inside the orbit of Mercury multiple times over.

TRAPPIST-1's outer three planets — designated f, g and h — are in a chain of 3:2 resonances.

"The outer planets behave properly, so to speak, with the simpler expected resonances," said Gabriele Pichierri, who is a planetary scientist at Caltech, in a statement. "But the inner ones have resonances that are a bit spicier."

For example, the orbital periods of the two innermost planets, b and c, are in an 8:5 resonance, meaning planet b orbits eight times for every five orbits of planet c. Meanwhile, planets c and d are in a 5:3 resonance.

So, how did these complex arrangements arise?

Pichierri is the lead author of a new research paper that delves into the early history of TRAPPIST-1 to discover how its planets wound up in this delicate configuration. The crew found a story of a shifting protoplanetary disk of gas and dust combined with powerful torques that pushed the planets around.

The innermost planets would have formed first, so Pichierri and his team divided the TRAPPIST-1 system into two sub-groups — the inner planets b, c, d and e, and the outer planets f, g and h. (Unlike our solar system, in which the outer planets are gas giants, the outer planets of TRAPPIST-1 are rocky worlds.) Their modeling identified three phases in the evolution of the system.

Here's what the team found.

In the first phase, the four innermost planets all start life in 3:2 resonances with each other, so b and c are in a 3:2 orbital resonance, as are c and d, and d and e. As the inner planets formed out of material from the protoplanetary disk, and their burgeoning red dwarf star ignited nuclear fusion in its core and produced radiation that began to dissipate the disk, the inner edge of the disk would have receded outwards.

In the second phase, planet e, anchored in the receding inner edge of the disk, would have found itself being dragged outwards, away from planets b, c and d and towards the worlds forming in the outer part of the system. This had the effect of causing the orbits of planets b, c and d to waver, and they crossed through the 8:5 and 5:3 resonances as their orbital periods widened, but were then pushed back via a gravitational torque (a twisting, rotational force) from the outer system, until they settled into the 8:5 and 5:3 resonances that they have today.

What of planet e, though? By the final phase, the three outer worlds had formed. Often, when planets form in a protoplanetary disk, they shed orbital angular momentum, exchanging this angular momentum with the disk that they are accreting material from in order to grow. This results in them migrating towards the inner edge of the disk. In the TRAPPIST-1 system, this likely had the effect of pushing planet e back, until the inner and outer parts of the planetary system settled into the configuration that they are in today.

"By looking at TRAPPIST-1, we have been able to test exciting new hypotheses for the evolution of planetary systems," said Pichierri. "TRAPPIST-1 is very interesting because it is so intricate: it’s a long planetary chain, and it’s a great exemplar for testing alternative theories about planetary system formation."

The research was published on Aug. 20 in the journal Nature Astronomy.