Astronomy

The dwarf planet Quaoar has a ring that is too big for its metaphorical fingers. While all other rings in the solar system lie within or near a mathematically determined distance of their parent bodies, Quaoar’s ring is much farther out.

“For Quaoar, for the ring to be outside this limit is very, very strange,” says astronomer Bruno Morgado of the Federal University of Rio de Janeiro. The finding may force a rethink of the rules governing planetary rings, Morgado and colleagues say in a study published February 8 in Nature.

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Quaoar is an icy body about half the size of Pluto that’s located in the Kuiper Belt at the solar system’s edge (SN: 8/23/22). At such a great distance from Earth, it’s hard to get a clear picture of the world.

So Morgado and colleagues watched Quaoar block the light from a distant star, a phenomenon called a stellar occultation. The timing of the star winking in and out of view can reveal details about Quaoar, like its size and whether it has an atmosphere.

The researchers took data from occultations from 2018 to 2020, observed from all over the world, including Namibia, Australia and Grenada, as well as space. There was no sign that Quaoar had an atmosphere. But surprisingly, there was a ring. The finding makes Quaoar just the third dwarf planet or asteroid in the solar system known to have a ring, after the asteroid Chariklo and the dwarf planet Haumea (SN: 3/26/14; SN: 10/11/17).

Even more surprisingly, “the ring is not where we expect,” Morgado says.

Known rings around other objects lie within or near what’s called the Roche limit, an invisible line where the gravitational force of the main body peters out. Inside the limit, that force can rip a moon to shreds, turning it into a ring. Outside, the gravity between smaller particles is stronger than that from the main body, and rings will coalesce into one or several moons.

“We always think of [the Roche limit] as straightforward,” Morgado says. “One side is a moon forming, the other side is a ring stable. And now this limit is not a limit.”

For Quaoar’s far-out ring, there are a few possible explanations, Morgado says. Maybe the observers caught the ring at just the right moment, right before it turns into a moon. But that lucky timing seems unlikely, he notes.

Maybe Quaoar’s known moon, Weywot, or some other unseen moon contributes gravity that holds the ring stable somehow. Or maybe the ring’s particles are colliding in such a way that they avoid sticking together and clumping into moons.

The particles would have to be particularly bouncy for that to work, “like a ring of those bouncy balls from toy stores,” says planetary scientist David Jewitt of UCLA, who was not involved in the new work.

The observation is solid, says Jewitt, who helped discover the first objects in the Kuiper Belt in the 1990s. But there’s no way to know yet which of the explanations is correct, if any, in part because there are no theoretical predictions for such far-out rings to compare with Quaoar’s situation.

That’s par for the course when it comes to the Kuiper Belt. “Everything in the Kuiper Belt, basically, has been discovered, not predicted,” Jewitt says. “It’s the opposite of the classical model of science where people predict things and then confirm or reject them. People discover stuff by surprise, and everyone scrambles to explain it.”

More observations of Quaoar, or more discoveries of seemingly misplaced rings elsewhere in the solar system, could help reveal what’s going on.

“I have no doubt that in the near future a lot of people will start working with Quaoar to try to get this answer,” Morgado says. More

SEATTLE — Luke Skywalker’s home planet in Star Wars is the stuff of science fiction. But Tatooine-like planets in orbit around pairs of stars might be our best bet in the search for habitable planets beyond our solar system.

Many stars in the universe come in pairs. And lots of those should have planets orbiting them (SN: 10/25/21). That means there could be many more planets orbiting around binaries than around solitary stars like ours. But until now, no one had a clear idea about whether those planets’ environments could be conducive to life. New computer simulations suggest that, in many cases, life could imitate art.

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Earthlike planets orbiting some configurations of binary stars can stay in stable orbits for at least a billion years, researchers reported January 11 at the American Astronomical Society meeting. That sort of stability, the researchers propose, would be enough to potentially allow life to develop, provided the planets aren’t too hot or cold.

Of the planets that stuck around, about 15 percent stayed in their habitable zone — a temperate region around their stars where water could stay liquid — most or even all of the time.

The researchers ran simulations of 4,000 configurations of binary stars, each with an Earthlike planet in orbit around them. The team varied things like the relative masses of the stars, the sizes and shapes of the stars’ orbits around each other, and the size of the planet’s orbit around the binary pair.

The scientists then tracked the motion of the planets for up to a billion years of simulated time to see if the planets would stay in orbit over the sorts of timescales that might allow life to emerge.

A planet orbiting binary stars can get kicked out of the star system due to complicated interactions between the planet and stars. In the new study, the researchers found that, for planets with large orbits around star pairs, only about 1 out of 8 were kicked out of the system. The rest were stable enough to continue to orbit for the full billion years. About 1 in 10 settled in their habitable zones and stayed there.

Of the 4,000 planets that the team simulated, roughly 500 maintained stable orbits that kept them in their habitable zones at least 80 percent of the time.

“The habitable zone . . . as I’ve characterized it so far, spans from freezing to boiling,” said Michael Pedowitz, an undergraduate student at the College of New Jersey in Ewing who presented the research. Their definition is overly strict, he said, because they chose to model Earthlike planets without atmospheres or oceans. That’s simpler to simulate, but it also allows temperatures to fluctuate wildly on a planet as it orbits.

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“An atmosphere and oceans would smooth over temperature variations fairly well,” says study coauthor Mariah MacDonald, an astrobiologist also at the College of New Jersey. An abundance of air and water would potentially allow a planet to maintain habitable conditions, even if it spent more of its time outside of the nominal habitable zone around a binary star system.

The number of potentially habitable planets “will increase once we add atmospheres,” MacDonald says, “but I can’t yet say by how much.”

She and Pedowitz hope to build more sophisticated models in the coming months, as well as extend their simulations beyond a billion years and include changes in the stars that can affect conditions in a solar system as it ages.

The possibility of stable and habitable planets in binary star systems is a timely issue says Penn State astrophysicist Jason Wright, who was not involved in the study.

“At the time Star Wars came out,” he says, “we didn’t know of any planets outside the solar system, and wouldn’t for 15 years. Now we know that there are many and that they orbit these binary stars.”

These simulations of planets orbiting binaries could serve as a guide for future experiments, Wright says. “This is an under-explored population of planets. There’s no reason we can’t go after them, and studies like this are presumably showing us that it’s worthwhile to try.” More

The night sky has been brightening faster than researchers realized, thanks to the use of artificial lights at night. A study of more than 50,000 observations of stars by citizen scientists reveals that the night sky grew about 10 percent brighter, on average, every year from 2011 to 2022.

In other words, a baby born in a region where roughly 250 stars were visible every night would see only 100 stars on their 18th birthday, researchers report in the Jan. 20 Science.

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The perils of light pollution go far beyond not being able to see as many stars. Too much brightness at night can harm people’s health, send migrating birds flying into buildings, disrupt food webs by drawing pollinating insects toward lights instead of plants and may even interrupt fireflies trying to have sex (SN: 8/2/17; SN: 8/12/15).

“In a way, this is a call to action,” says astronomer Connie Walker of the National Optical-Infrared Astronomy Research Laboratory in Tucson. “People should consider that this does have an impact on our lives. It’s not just astronomy. It impacts our health. It impacts other animals who cannot speak for themselves.”

Walker works with the Globe at Night campaign, which began in the mid-2000s as an outreach project to connect students in Arizona and Chile and now has thousands of participants worldwide. Contributors compare the stars they can see with maps of what stars would be visible at different levels of light pollution, and enter the results on an app.

“I’d been quite skeptical of Globe at Night” as a tool for precision research, admits physicist Christopher Kyba of the GFZ German Research Centre for Geosciences in Potsdam. But the power is in the sheer numbers: Kyba and colleagues analyzed 51,351 individual data points collected from 2011 to 2022.

“The individual data are not precise, but there’s a whole lot of them,” he says. “This Globe at Night project is not just a game; it’s really useful data. And the more people participate, the more powerful it gets.”

Those data, combined with a global atlas of sky luminance published in 2016, allowed the team to conclude that the night sky’s brightness increased by an average 9.6 percent per year from 2011 to 2022 (SN: 6/10/16).

Most of that increase was missed by satellites that collect brightness data across the globe. Those measurements saw just a 2 percent increase in brightness per year over the last decade.

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There are several reasons for that, Kyba says. Since the early 2010s, many outdoor lights have switched from high-pressure sodium lightbulbs to LEDs. LEDs are more energy efficient, which has environmental benefits and cost savings.

But LEDs also emit more short-wavelength blue light, which scatters off particles in the atmosphere more than sodium bulbs’ orange light, creating more sky glow. Existing satellites are not sensitive to blue wavelengths, so they underestimate the light pollution coming from LEDs. And satellites may miss light that shines toward the horizon, such as light emitted by a sign or from a window, rather than straight up or down.

Satellites have missed some of the light pollution from LEDs, which emit in blue wavelengths. This image from the International Space Station shows LEDs in the center of Milan glowing brighter than the orange lights in the suburbs.Samantha Cristoforetti, NASA, ESA

Astronomer and light pollution researcher John Barentine was not surprised that satellites underestimated the problem. But “I was still surprised by how much of an underestimate it was,” he says. “This paper is confirming that we’ve been undercounting light pollution in the world.”

The good news is that no major technological breakthroughs are needed to help fix the problem. Scientists and policy makers just need to convince people to change how they use light at night — easier said than done.

“People sometimes say light pollution is the easiest pollution to solve, because you just have to turn a switch and it goes away,” Kyba says. “That’s true. But it’s ignoring the social problem — that this overall problem of light pollution is made by billions of individual decisions.”

Some simple solutions include dimming or turning off lights overnight, especially floodlighting or lights in empty parking lots.

Kyba shared a story about a church in Slovenia that switched from four 400-watt floodlights to a single 58-watt LED, shining behind a cutout of the church to focus the light on its facade. The result was a 96 percent reduction in energy use and much less wasted light , Kyba reported in the International Journal of Sustainable Lighting in 2018. The church was still lit up, but the grass, trees and sky around it remained dark.

“If it was possible to replicate that story over and over again throughout our society, it would suggest you could really drastically reduce the light in the sky, still have a lit environment and have better vision and consume a lot less energy,” he says. “This is kind of the dream.”

Barentine, who leads a private dark-sky consulting firm, thinks widespread awareness of the problem — and subsequent action — could be imminent. For comparison, he points to a highly publicized oil slick fire on the Cuyahoga River, outside of Cleveland, in 1969 that fueled the environmental movement of the 1960s and ’70s, and prompted the U.S. Congress to pass the Clean Water Act.

“I think we’re on the precipice, maybe, of having the river-on-fire moment for light pollution,” he says. More

Galaxies that helped transform the early universe may have been small, round and green.

Astronomers using the James Webb Space Telescope have spotted “Green Pea” galaxies dating to 13.1 billion years ago. These viridescent runts, spotted just 700 million years after the Big Bang, might have helped trigger one of the greatest makeovers in cosmic history, astronomers said at a January 9 news conference in Seattle at the American Astronomical Society’s annual meeting.

Green Peas first showed up in 2009 in images from the Sloan Digital Sky Survey, an ambitious project to map much of the sky. Citizen science volunteers gave the objects their colorful name. Their greenish hue is because most of their light comes from glowing gas clouds, rather than directly from stars.

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These galaxies are rare in the present-day universe. Astronomers think that the ones that do exist are analogs of galaxies that were more plentiful in the early universe.

“They’re a bit like living fossils,” said astrophysicist James Rhoads of NASA’s Goddard Space Flight Center in Greenbelt, Md. “Coelacanths, if you will,” referencing a fish thought to be extinct until it showed up off the coast of South Africa in 1938 (SN: 12/2/11). 

These galaxies leak much more ultraviolet light, which can rip electrons from atoms, than typical galaxies do. So Green Peas dating to the universe’s first billion years or so could be partly responsible for a dramatic and mysterious cosmic transition called reionization, when most of the hydrogen atoms in the early universe had their electrons torn away (SN: 1/7/20).

Three ancient Green Peas turned up in JWST’s first image, released in July 2022 (SN: 7/21/22). The objects look red in JWST’s infrared vision, but the wavelengths of light they emit are like those of the previously discovered Green Peas. The findings were also published in the Jan. 1 Astrophysical Journal Letters.

“This helps us explain how the universe reionized,” Rhoads said. “I think this is an important piece of the puzzle.” More

While the stunning images from the James Webb Space Telescope captured space fans’ attention this year, other telescopes and spacecraft were busy on Earth and around the solar system (SN Online: 12/7/22). Here are some of the coolest space highlights that had nothing to do with JWST.

Back to the moon

After several aborted attempts, NASA launched the Artemis I mission on November 16. That was a big step toward the goal of landing people on the moon as early as 2025 (SN: 12/3/22, p. 14). No human has set foot there since 1972. Artemis I included a new rocket, the Space Launch System, which had previously suffered a series of hydrogen fuel leaks, and the new Orion spacecraft. No astronauts were aboard the test flight, but Orion carried a manikin in the commander’s seat and two manikin torsos to test radiation protection and life-support systems, plus a cargo hold full of small satellites that went off on their own missions. On December 11, the Orion capsule successfully returned to Earth, splashing down in the Pacific Ocean near Mexico (SN Online: 12/12/22).

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DART shoves an asteroid

NASA’s DART spacecraft successfully nudged an asteroid into a new orbit this year. On September 26, the Double Asteroid Redirection Test slammed into asteroid Dimorphos, about 11 million kilometers from Earth at the time of impact. In October, NASA announced that the impact shortened Dimorphos’ roughly 12-hour orbit around its sibling asteroid, Didymos, by 32 minutes (SN: 11/5/22, p. 14). Dimorphos posed no threat to Earth, but the test will help inform future missions to divert any asteroids on a potentially dangerous collision course with our home planet, researchers say.

This image from the Hubble Space Telescope shows a split stream of dust and rock streaming off the asteroid Dimorphos nearly 12 days after the DART spacecraft smashed into it.NASA, ESA, STSCI, HUBBLE

Massive Marsquakes

The InSight Mars lander is going out on a high note. After scientists reported in May that InSight had recorded the largest known Marsquake, roughly a magnitude 5, news came in October that the lander’s seismometer had also detected the rumblings of the two biggest meteorite impacts ever observed on Mars. Those impacts created gaping craters and sent seismic waves rippling along the top of the planet’s crust.

The details of how those waves and others moved through the Red Planet gave researchers new intel on the structure of Mars’ crust, which is hard to study any other way. The data also suggest that some Marsquakes are caused by magma moving beneath the surface (SN: 12/3/22, p. 12). The solar panels that power the lander are now covered in dust after four years on Mars, a death knell for the mission.

InSight’s seismometer, seen in the lower left of this artist’s rendition of the lander, detected Mars’ largest known quake this year.JPL-CALTECH/NASA

Chemistry of life turns up in meteorites

All five bases in DNA and RNA have been found in rocks that fell to Earth. Three of the nucleobases, which combine with sugars and phosphates to make up the genetic material of all known life, had previously been found in meteorites. But the last two — cytosine and thymine — were reported from space rocks only this year (SN: 6/4/22, p. 7). The find supports the idea that life’s precursors could have come to Earth from space, researchers say.

A two-gram chunk from this piece of meteorite contains two crucial components of DNA and RNA now identified for the first time in an extraterrestrial source.NASA

Sagittarius A* snapshot

The supermassive black hole at the center of the Milky Way became the second black hole to get its close-up. After releasing a picture of the behemoth at the heart of galaxy M87 in 2019, astronomers used data from the Event Horizon Telescope, a network of radio telescopes around the world, to assemble an image of Sagittarius A* (SN: 6/4/22, p. 6). The image, released in May, shows a faint fuzzy shadow nestled in the glowing ring of the accretion disk. That may not sound impressive on its own, but the result provides new details about the turbulence roiling near our black hole’s edge.

The Event Horizon Telescope revealed this first-ever image of our galaxy’s supermassive black hole.Event Horizon Telescope Collaboration More

BALTIMORE — When the James Webb Space Telescope was first dreamed up, exoplanets hadn’t even been discovered yet. Now the observatory is showing astronomers what it can learn about planets orbiting other stars — including the small ones.

Since its launch in December 2021, JWST had already “sniffed” the atmospheres of Jupiter-sized planets orbiting searingly close to their stars (SN: 8/26/22). Those intense worlds are interesting, but not the places where astronomers hope to look for signs of life. The telescope is now getting glimpses of atmospheres on known exoplanets of the more terrestrial persuasion, astronomers reported December 13 and 14 at the First Science Results from JWST conference.

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And JWST is starting to find new rocky worlds too.

These early peeks at far-off worlds don’t yet reveal a lot about these remote locales. But researchers are buoyed by what JWST’s sharp vision in infrared wavelengths could eventually unearth about the smaller planets beyond our solar system.

“The main message is, we’re in business,” said University of Montreal astronomer Björn Benneke. “We don’t even have all the observations yet, but they are already quite exciting.”

One of the smaller planets that JWST looked at is GJ 1214b, which has frustrated astronomers since its discovery in 2009 (SN: 12/16/09). The planet is a sub-Neptune, meaning its size is somewhere between that of a rocky world like Earth and a gaseous one like Neptune.

“What the heck are sub-Neptunes?” asked astronomer Eliza Kempton of the University of Maryland in College Park. They could be balls of rock with thick hydrogen and helium atmospheres, or maybe water worlds (SN: 2/22/12). “What we’d like to do with atmospheric characterization is measure their atmospheres and see which is which,” Kempton said.

Previously, astronomers tried to observe the makeup of GJ 1214b’s atmosphere by watching how starlight filtered through it. But the atmosphere is thick and hazy, blocking astronomers’ ability to detect individual molecules in it.

Instead of watching the planet pass in front of its star, Kempton and colleagues used JWST to look for the glow of the planet right before it disappeared behind the star. And it worked: After 38 hours of observing, the researchers detected the planet’s infrared glow, Kempton said in a December 13 presentation.

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There’s more work to do, but the initial data suggest the planet has a lot of chemical components, possibly including water and methane. It’s also enriched in elements heavier than hydrogen and helium.

As for knowing what kind of world GJ 1214b is, “I’d say we’re not quite there yet,” Kempton said. It could be a watery planet, she said, or a gassy planet that has lost a fair amount of its lighter elements.

The telescope also had its first look at the tantalizing TRAPPIST-1 system, Benneke said in a different December 13 presentation (SN: 12/13/17). Discovered in 2017, the system contains seven Earth-sized worlds that are probably rocky. Three of those planets might have the right temperatures for liquid water to exist on their surface, making them particularly interesting targets for JWST and other telescopes to look for signs of life.

But TRAPPIST-1 is a small, red star called an M dwarf, a type of star that is notorious for violent flares and strong radiation. For years, astronomers have debated whether planets around these stars would be hospitable to life, or if the stars would strip their planets’ atmospheres away (SN: 6/14/17).

“If the TRAPPIST planets don’t have atmospheres, then we need to move on” from M dwarfs in the search for extraterrestrial life, says astronomer Mercedes Lόpez-Morales of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., who was not involved in the new JWST observations.

JWST’s first look at one of those potentially habitable worlds, TRAPPIST-1g, did not reveal any clear signs of an atmosphere. But the telescope looked at the planet for only about five hours. With more observations, an atmosphere should be detectable if it’s there, Benneke said.

JWST is getting into the planet-hunting game too, said astronomer Kevin Stevenson on December 14. The telescope double-checked a potentially interesting observation from another telescope and confirmed that it had seen a rocky, Earth-sized world around a nearby M dwarf. This proves that JWST has the precision to find such worlds.

“It is an exciting result, perhaps the first discovery of an exoplanet by JWST,” said Stevenson, of the Space Telescope Science Institute in Baltimore. The planet orbits its dim star every two days, so it’s probably around 225° Celsius on the surface — likely too hot to be habitable, he says. “It’s more like an exo-Venus than an exo-Earth.”

While it’s still early days, the researchers emphasized, the forecast for planet hunting using JWST is good.

The results are paving the way for future observatories too, said astrophysicist John Mather of NASA’s Goddard Space Flight Center in Greenbelt, Md. Astronomers’ wish list for future missions includes a telescope that can dig even further into the details of potentially habitable worlds.

“If it’s not impossible,” Mather said, “let’s do it.” More

The first planet ever spotted by the Kepler space telescope is falling into its star.

Kepler launched in 2009 on a mission to find exoplanets by watching them cross in front of their stars. The first potential planet the telescope spotted was initially dismissed as a false alarm, but in 2019 astronomer Ashley Chontos and colleagues proved it was real (SN: 3/5/19). The planet was officially named Kepler 1658b.

Now, Chontos and others have determined Kepler 1658b’s fate. “It is tragically spiraling into its host star,” says Chontos, now at Princeton University. The planet has roughly 2.5 million years left before it faces a fiery death. “It will ultimately end up being engulfed. Death by star.”

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The roughly Jupiter-sized planet is searingly hot, orbiting its star once every three days. In follow-up observations from 2019 to 2022, the planet kept transiting the star earlier than expected.

Combined data from Kepler and other telescopes show that the planet is inching closer to the star, Chontos and colleagues report December 19 in the Astrophysical Journal Letters.

“You can see the interval between the transits is shrinking, really slowly but really consistently, at a rate of 131 milliseconds per year,” says astrophysicist Shreyas Vissapragada of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.

That doesn’t sound like much. But if this trend continues, the planet has only 2 million or 3 million years left to live. “For something that’s been around for 2 to 3 billion years, that’s pretty short,” Vissapragada says. If the planet’s lifetime was a more human 100 years, it would have a little more than a month left.

Studying Kepler 1658b as it dies will help explain the life cycles of similar planets. “Learning something about the actual physics of how orbits shrink over time, we can get a better handle on the fates of all of these planets,” Vissapragada says. More

BALTIMORE — The James Webb Space Telescope is living up to its promise as a wayback machine. The spectacularly sensitive observatory is finding and confirming galaxies more distant, and therefore existing earlier in the universe’s history, than any seen before.

The telescope, also known as JWST, has confirmed extreme distances to four galaxies, one of which sets a record for cosmic remoteness by shining about 13.475 billion years ago, astronomers reported December 12 at the First Science Results from JWST conference. Dozens of other galaxies may have been spotted as they were just 550 million years or less after the Big Bang, meaning the light from those galaxies traveled at least 13.1 billion years before reaching the telescope.

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Taken together, the new observations suggest galaxies formed earlier and faster than previously thought. “We’re entering a new era,” says astronomer Swara Ravindranath of the Space Telescope Science Institute in Baltimore.

That new era is thanks in part to JWST’s ability to see very faint infrared light (SN: 10/6/21). For the most distant objects, like the first stars and galaxies, their visible light is stretched by the relentless expansion of the universe into longer infrared wavelengths that are invisible to human eyes and some previous space telescopes. But now, measurements that were recently impossible are suddenly easy with JWST, researchers say.

“JWST is the most powerful infrared telescope that has ever been built,” astrophysicist Jane Rigby said at the conference. Rigby, of NASA’s Goddard Space Flight Center in Greenbelt, Md., is the JWST operations project scientist. “Almost across the board, the science performance is better than expected.”

Even in the very first image, released in July, astronomers spotted galaxies whose light originated 13 billion years ago or more (SN: 7/11/22). But those distances were estimates. To measure the distances precisely, astronomers need spectra, measurements of how much light the galaxies emit across many wavelengths. Those measurements are slower and more difficult to make than pictures.

“Thanks to this glorious telescope, we’re now getting spectra … for hundreds of galaxies at once,” said astronomer Emma Curtis-Lake of the University of Hertfordshire in England.

Among those are four of the earliest galaxies ever seen, some of which existed less than 400 million years after the Big Bang, Curtis-Lake and colleagues reported at the meeting and in a paper submitted December 8 to arXiv.org. The team spotted these record holders in a patch of sky that the Hubble Space Telescope once scoured for ultra-remote galaxies (SN: 1/3/10).

The previous distance record holder existed between 13.3 billion and 13.4 billion years ago, or about 400 million years after the Big Bang (SN: 1/28/20). JWST confirmed the distance to that galaxy and came back with three more whose light comes from as early as 325 million years after the Big Bang.

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The galaxies are also surprisingly pristine, chemically speaking, lacking in elements heavier than hydrogen and helium.

“We don’t see that in the present-day universe,” says Ravindranath, who was not involved in the new discovery. It could mean that not many of the galaxies’ stars have died in supernova explosions that spread heavy elements around the universe, which suggests the galaxies’ original stars were not extremely massive.

In another part of the sky, JWST has spotted 26 galaxies that may have existed about 550 million years or earlier after the Big Bang, astronomer Steven Finkelstein and colleagues reported at the meeting and in a paper submitted November 10 to arXiv.org.

“On an emotional, visceral level, looking at these images is amazing,” said Finkelstein, of the University of Texas at Austin.

The first of these to be discovered, dubbed Maisie’s Galaxy after Finkelstein’s daughter, appears to be just 380 million years after the Big Bang, the researchers reported December 1 in the Astrophysical Journal Letters. The most distant galaxy in the team’s survey might lie as much as 130 million years earlier than Maisie. Those galaxies’ distances still need to be confirmed with spectra, but the team expect to get those data in the next few weeks.

This fuzzy red dot in the inset box at right is Maisie’s Galaxy as seen with JWST. If new measurements of the wavelengths of light it is emitting confirm its distance, astronomers may be seeing this galaxy as it was less than 400 million years after the Big Bang.NASA, STScI, CEERS, TACC, S. Finkelstein, M. Bagley, Z. Levay

And distant galaxies that lie behind a massive galaxy cluster called Abell 2744 are also more numerous and distant than expected, astrophysicist Guido Roberts-Borsani of UCLA said at the meeting.

Before JWST observed the cluster, astronomers predicted it should find effectively zero galaxies from 13.2 billion years ago. “But we found two,” said Roberts-Borsani, who reported the results at the meeting. “So something’s a little bit weird.” It could mean that galaxies form earlier and faster than thought, he said, although it could also mean that JWST was just looking at a particularly galaxy-rich patch of the sky.

All these new galaxies are exciting because they could be responsible for making the universe transparent to visible light, a process astronomers call reionization (SN: 12/2/22). Before the first stars ignited, the universe was filled with a hot dense soup of particles. The first stars and galaxies bathed the universe in ultraviolet light, splitting electrons off hydrogen atoms and allowing light to zip through until it reached JWST.

The new data, Roberts-Borsani said, “give us constraints on when this process started, ended, and which galaxies were the culprits for this process.” More