A dried-out felt-tip marker and a snapped-off piece of molded black plastic sold for $857,600 at a Sotheby's auction on Wednesday.

What otherwise might have been worthless bits of trash commanded the highest bids due to where the two items were 57 years ago—lifting off aboard NASA's Apollo 11 spacecraft on humanity's first mission to land astronauts on the Moon. More than flown odds and ends, one was the problem that almost stranded Neil Armstrong and Buzz Aldrin on the lunar surface, and the other was the simple solution to saving the mission.

"Houston, Tranquility. Do you have a way of showing the configuration of the engine arm circuit breaker?" radioed Aldrin to Mission Control after realizing he or Armstrong had inadvertently broken off the top of the circuit breaker switch that would enable their ascent engine to ignite, beginning their trip back to Earth. "The reason I'm asking is because the end of it appears to be broken off. I think we can push it back in again. I'm not sure we could pull it out if we pushed it in, though."

As engineers on the ground worked to devise a workaround, Aldrin came up with a straightforward idea, as he described decades later in the letter accompanying the artifacts' sale.

Apollo 11 astronaut Buzz Aldrin's letter describing the broken circuit breaker switch and felt-tip pin from his Moon mission. Credit: Sotheby's

"While I could have stuck my finger in and reset the switch, there was electricity flowing through the breaker and I did not want to electrocute myself. I had a plastic felt tip pen in one of my suit pockets and it fit into the breaker opening, so I pushed the marker pen into the circuit breaker, it clicked on, and we rearmed the Engine Arm circuit," he wrote.

"Now we could leave the lunar surface," Aldrin said, "rendezvous with Mike Collins in the command module, and head for home. Disaster averted."

Storied switch

The tale of the pen and circuit breaker is well known, having been recounted by Aldrin in his books and talks, as well as for years having been included on the pamphlet packaged with every Fisher Space Pen sold until Aldrin pointed out that as an engineer, he would never insert a metal-tipped writing instrument into a live electrical socket. The pen he used, which was sold on Wednesday, was a Duro-brand Rocket felt-tip marker.

Aldrin also loaned the pen and broken-off circuit breaker switch to the Smithsonian for its "Destination Moon" traveling exhibit featuring the Apollo 11 command module "Columbia." The tour visited five US cities over the course of two years, spanning the 50th anniversary of the first Moon landing in 2019.

The location of the engine arm circuit breaker switch in the Apollo lunar module that was broken off on Apollo 11. Credit: NASA

A law enacted in 2012 reaffirmed that Aldrin and his fellow Apollo-era astronauts legally had title to the spacecraft hardware and other crew equipment they kept as mementos from their missions. The pieces are theirs to own, sell, trade, or donate as they desire.

This was at least the second time that the pen and switch had been offered for sale. In 2022, Sotheby's listed the same set as part of its "Buzz Aldrin: American Icon" sale. Despite eliciting bids up to $650,000, the lot failed to reach its reserve and was passed.

This time, the bids reached $670,000, and it was sold on behalf of the Buzz Aldrin Family Trust. The $857,600 total includes the buyer's premium assessed by Sotheby's. The winning bidder was not identified other than as a participant by phone.

Not a record-setter

While the sale price was impressive, the pen and switch did not break into the top 10 list of the highest prices at a public sale for space artifacts and memorabilia. That ranking begins at $1.625 million, the amount paid in 2015 for a Bulova watch worn outside on the surface of the Moon during the 1971 Apollo 15 mission and tops out at the $2,882,500 spent for the former Soviet Union's Vostok 3KA-2 space capsule as auctioned by Sotheby's in 2011.

The broken circuit breaker switch that nearly ended Apollo 11, and the pen that Buzz Aldrin used to save himself and Neil Armstrong. Credit: Sotheby's

As a point of comparison, the second-highest price for a space-flown artifact was the $2,772,500 commanded by Aldrin's Apollo 11 in-flight jacket, which Sotheby's sold in 2022.

Wednesday's "Space Exploration" sale was part of Sotheby's annual Geek Week of science and technology-themed auctions. The sale offered 134 lots, including more than 40 items from Aldrin's collection. In total, it brought in $2,862,336.

A modern Moonshine gold Omega Speedmaster chronograph, one of 24 watches consigned by the Aldrin Family Trust, sold for $70,400. The same 2026 model is still for sale from Omega for $53,500 retail.

Another sale highlight, and the only item other than the pen and switch set to sell for six figures, was the pressure hatch from the Skylab III command module, flown to and from the United States' first space station in 1974. It sold for $192,000.

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Forget the sale of the century. The auction house Sotheby’s has geared up for the sale of the epoch. On July 14 it opened live bidding on assorted fossils, but the pièce de résistance is lot 20, a rare 67-million-year-old Tyrannosaurus rex skeleton.

The specimen—dubbed Gus—is billed as one of the largest, most complete T. rexes ever found. Gus is expected to fetch up to $30 million and will go to the highest bidder, whether public museum or private collector. The latter have played an increasingly prominent role in buying fossils, with auction houses, according to paleontologists, contributing to the trend by building hype. But when private collectors swoop in and buy fossils at auction as luxury assets, those pieces of history are effectively lost to science.

By nearly all accounts, Gus is a big deal. In its description, Sotheby’s boasts that the specimen, which was discovered on a ranch in South Dakota, comprises “an incredible 183 fossil bone elements” making it “approximately 61% complete by bone count.” The fossil remains have been mounted in a custom steel armature along with replicas of the missing bones. The result is a reconstructed skeleton posed as if in hot pursuit, its mouth full of dagger teeth ready to tear into prey.

“It does seem to be a spectacular specimen,” says Thomas Holtz, a tyrannosaur specialist at the University of Maryland. The completeness of the skeleton and the high quality of the bone make Gus “scientifically significant,” he says.

Gus is the latest major dinosaur fossil to go up for sale at auction in the US. That trend began in earnest in 1997 when Sotheby’s auctioned Sue, the most complete T. rex on record. That specimen sold for roughly $8.4 million—the most money ever paid for a fossil at auction at the time.

“Before Sue was sold, there were no laws about who owned fossils. There was no value truly ascribed to them,” says Cassandra Hatton, vice chairman and head of the science and natural history department at Sotheby’s. In many other countries the state owns the fossils. But court cases around Sue clarified that in the US, whoever owns the land also owns whatever fossils are on it, Hatton explains. The market has been booming ever since.

But whereas Sue went to a scientific institution—the Field Museum in Chicago—in recent years ultrarich individuals have been snapping up dinosaur fossils at auctions for their private collections, prompting paleontologists to be concerned about the fate of rare specimens. Tech entrepreneur Dan O’Dowd owns a T. rex called Samson. And he’s not the only private collector to own a tyrant lizard king. A study published in 2025 found that there are more fossils of T. rex in private collections than there are in public trusts.

It’s not just T. rex that’s ending up in personal coffers. In 2024, Sotheby’s sold a Stegosaurus named Apex to hedge fund billionaire Ken Griffin for the record-setting sum of $44.6 million. And last year the auction house sold the only known juvenile Ceratosaurus in the world to an anonymous buyer for $30.5 million. These examples highlight another trend: As prices soar, museums simply cannot compete at auction.

Credit: Courtesy of Matthew Sherman/Sotheby's

Auction houses say the sales help science by rescuing fossils from the erosion that occurs when they are exposed to the elements, and by helping to get them expertly excavated, prepared, and assessed.

“If a fossil is not excavated, it’s lost to everyone,” Hatton says.

Paleontologists counter that the incentive to sell specimens to the highest bidder and appeal to high-net-worth collectors actively undermines science every step of the way. That begins at excavation, with commercial outfits that take the fossils out of the ground but fail to exhaustively document the geological context in which a fossil was found, which is essential for understanding the age of the organism, how it died, and the ecosystem it inhabited. Mounting the bones for artistic display makes them impossible to study using modern techniques such as computed tomographic imaging, which can reveal hidden features of fossils noninvasively.

Paleontologists also argue that the auction firms play it fast and loose with science to market the fossils in a way that may make them more appealing to untrained buyers. In the case of Gus, Sotheby’s describes holes in the jaw and elsewhere on the specimen as tyrannosaurid bite marks—signs that Gus might have battled with or been scavenged by his own kind. The description does not offer any evidence to support this interpretation of the holes, nor does it mention alternative explanations for such damage.

It’s a dramatic story, but it’s probably wrong, according to Stuart Sumida, a paleontologist at California State University, San Bernardino. Puncture marks are irregularly shaped and have splintered fractures around the edges. The holes on Gus’ bones, in contrast, are perfectly round and smooth-edged. Holes like these are common on tyrannosaur bones and have been previously hypothesized to be the result of infections. “It’s much sexier to say they’re puncture wounds, but this isn’t how puncture wounds look,” Sumida says of the hole in Gus’ jaw. “T. rex probably just had really bad breath.”

When asked by WIRED about the origin of the bite-mark claim, Hatton replied, “The bite marks are very clear, and are not all straight punctures but lateral bites where you can clearly see the shape of the tooth. You can also tell from the edges of the hole whether the break is clean, or if the hole is gradual (which would be more likely the result of a parasitic or other infection that gradually and evenly eats the bone)." She did not indicate where this analysis came from.

But the central issue with auctioning fossils, researchers contend, is that when specimens end up in private hands, they become unavailable for scientific study. Even if a private collector loans a fossil out for display or study at a museum, as happened last year when the American Museum of Natural History in New York City secured a four-year loan of Griffin’s Stegosaurus, such an arrangement violates a central tenet of paleontology: Scientific reproducibility requires that researchers other than those conducting the original examination have access to those same fossils in perpetuity.

That approach allows paleontologists to validate findings, test new hypotheses, and build knowledge of the past. To ensure access, fossils must be held in public repositories on a permanent basis. So vital is this covenant that established scientific journals won’t publish a study on a specimen that isn’t in the custody of a publicly accessible museum, Sumida explains.

Everything scientists have been able to piece together from fossils about prehistory—from the origin of multicellular life to the dawn of humankind—rests on this system.

“A scientifically important fossil isn't just a static object; it's a permanent source of data that future generations of scientists will study with tools that haven't even been invented yet—but only if the fossil remains in the public trust,” says Kristi Curry Rogers, a paleontologist at Macalester College. “Think about all the cool discoveries that have been made in the last 50 years about dinosaur diets, body temperatures, coloration, reproduction, vocalization, neurobiology—none of these discoveries would have been possible if the fossils had disappeared into private collections."

Sales of fossils to private individuals in the US won’t stop, Sumida acknowledges. So he and Rogers are taking a different tack to help keep important fossils in science’s fold. In their respective roles as president and vice president of the Society of Vertebrate Paleontology, they are working to set up the society to act as a liaison between private collectors and museums. Their goal is to persuade private collectors to donate the fossils they buy to science museums right after the gavel falls rather than keeping them as trophy acquisitions.

“When it comes to these public auctions of our shared history, the best outcome is when those with the means to acquire an extraordinary fossil choose to immediately place it in the public trust, where everyone benefits," Rogers says.

Private buyers can avoid the bad PR that comes from opposition to these sales by making their purchase anonymously, which could hinder efforts to persuade them to engage in philanthropy. But the Society of Vertebrate Paleontology is hoping that if it can convince even just a few known individuals to donate their fossils to science, they, in turn, will influence others to do the same.

The society is in talks with some collectors and museums, though Sumida declined to share specific details. It doesn’t have a plan in place to approach Gus’ buyer, but it might develop one depending on who purchases the fossil.

“A specimen of this quality deserves to be in a museum collection so that not merely the current generation but future researchers (to say nothing of museum-goers) would be able to study and admire it far into the future,” Holtz says of Gus. “Let us hope that whoever acquires it keeps this in mind.”

This story originally appeared at wired.com.

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Lettuce and salad greens have become the prime suspects in an explosive outbreak of the diarrheal parasite Cyclospora, which is surging nationwide but erupting to extraordinary heights in Michigan.

In recent years, Michigan has typically reported around 50 cases of cyclosporiasis, which causes urgent bouts of watery diarrhea, abdominal cramps, and nausea. But, this year, as of July 14, the state has reported 3,309 cases of the food-borne pathogen. Of those 44 have been hospitalized.

Based on interviews with more than 1,000 people sickened in Michigan, the latest data is pointing to leafy greens as the source, according to the Michigan Department of Health and Human Services (MDHHS).

"Although we do not have a definite product identified as the source of the outbreak, we want to let Michiganders know what we have learned so far so they can take steps to protect their families," Natasha Bagdasarian, Michigan's chief medical executive, said in an announcement. "Early information has shown lettuce as a common product that regularly comes up during the investigation. We will continue to provide updates as we learn more."

Taco Bell suspected

Separately, The Washington Post reported that state and federal officials are looking into whether Taco Bell restaurants may have been a source of food contaminated with the single-cell parasite.

According to local media sources in the Detroit area, Taco Bell restaurants put up signs reading, "We are currently unable to sell Lettuce, Cilantro, Onion, Pico de Gallo, and Guacamole due to a nationwide recall."

It's unclear what recall the restaurant is referring to; no nationwide recalls have been announced by Michigan or federal authorities related to cyclosporiasis cases. The Post reported that Taco Bell did not respond to multiple requests for comment on the signs or the decision to pull certain produce.

A source familiar with the investigation told the outlet that some sickened people interviewed reported having eaten at Taco Bells, while others did not, suggesting that there could be multiple sources of the contaminated food item.

Identifying the source of Cyclospora can be difficult because it can take up to two weeks between when a person eats contaminated food and when they develop symptoms, making recall of the possible food sources difficult, the MDHHS noted. They also pointed to the "complex food distribution networks" as complicating factors in tracking the source or sources.

National situation

While Michigan is seeing the highest numbers of cases, at least 31 states are also reporting illnesses. New York has reported 470 cases. Ohio is seeing at least 397 cases. North Carolina has reported at least 240. (The Centers for Disease Control and Prevention is collecting data on the cases, but is reporting them slowly.) The nationwide tally is well over 4,000 already at this point in the summer, which is when cyclosporiasis cases peak. In past years, the US has typically reported between 2,000 and 5,000 cases a year.

Amid the outbreak with no clear source as of yet, health officials are recommending that people be cautious about leafy greens, particularly bagged or boxed greens. It's recommended to instead buy whole heads of lettuce, discard the outer two or three layers of leaves, and then wash the rest thoroughly. But, sticking with peel-able or smooth-surfaced produce is safer. The safest choice is cooking produce to at least 158° F (70° C), which will kill the parasite.

Past cyclosporiasis outbreaks have been linked to bagged salad mixes and kits, fresh cilantro, fresh basil, raspberries, snow peas, and green onions, MDHHS notes.

People who experience frequent watery diarrhea should consult with their healthcare provider. An antimicrobial treatment can treat the infection, along with rest and hydration.

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Watering your lawn in the summer can be both pragmatic and fun with so-called "silly sprinklers," designed to create amusing loops and spirals of water jets. And there's some fascinating physics at work to boot. Researchers at New York University's Courant Institute conducted a series of experiments with different silly sprinkler designs to find the answer to a longstanding problem in fluid dynamics, according to a new paper published in the Proceedings of the National Academy of Sciences.

As previously reported, the reverse sprinkler problem is associated with physicist Richard Feynman because he popularized the concept, but it actually dates back to a chapter in Ernst Mach’s 1883 textbook The Science of Mechanics (Die Mechanik in Ihrer Entwicklung Historisch-Kritisch Dargerstellt). Mach’s thought experiment languished in relative obscurity until a group of Princeton University physicists began debating the issue in the 1940s.

Feynman was a graduate student there at the time and threw himself into the debate with gusto, even devising an experiment in the cyclotron laboratory to test his hypothesis. One might intuit that a reverse sprinkler would work just like a regular sprinkler, merely played backward, so to speak. But the physics turns out to be more complicated. “The answer is perfectly clear at first sight,” Feynman wrote in Surely You’re Joking, Mr. Feynman (1985). “The trouble was, some guy would think it was perfectly clear [that the rotation would be] one way, and another guy would think it was perfectly clear the other way.”

Mach proposed that there would be no rotation with a reverse sprinkler: the reaction force on the nozzle as it sucks in water pulls the nozzle counter-clockwise, while the water flowing into the inside of the nozzle pushes it clockwise. The two forces cancel each other out in this steady-state scenario. Feynman’s own experiment showed a slight tremor when pressure was first applied to pump water through the nozzle, and then the sprinkler returned to its original position and remained still.

Illustration of a “reaction wheel” from Ernst Mach’s Mechanik (1883). Credit: Public domain

But others suggested that if the friction was low enough and the inflow rate high enough, a reverse sprinkler would start to turn in the opposite direction of an ordinary sprinkler, thanks to the formation of a vortex inside. Since Feynman’s efforts, experiments have been all over the place: some showed steady reverse rotation, some showed only transient rotation, and some produced unsteady rotation that changed direction or flowed in a direction determined by the contraption's geometry.

When sprinklers get silly

In 2024, New York University applied mathematician Leif Ristroph and several colleagues built their own custom sprinkler that incorporated ultra-low-friction rotary bearings so their device could spin freely. They immersed their sprinkler in water and used a special apparatus to either pump water in or pull it out at carefully controlled flow rates. This let the team observe how water flowed inside, outside, and through the device. Adding dyes and microparticles to the water and illuminating them with lasers helped capture the flows on high-speed video. They ran their experiments for several hours at a time, the better to precisely map the fluid-flow patterns.

The team found that the reverse sprinkler rotates 50 times slower than a regular sprinkler, but it operates along similar mechanisms, which surprised them. Ristroph described the behavior as an “inside-out rocket,” where the internal jets shoot inside the chamber where the arms meet and collide—but they don't collide head-on, which results in the forces that rotate the sprinkler in reverse. By contrast, a forward sprinkler is more like a rotating rocket, with jets shooting out of its arms.

The 2024 experimentally observed flow patterns were in excellent agreement with the group’s mathematical models—which they dubbed the momentum flux theory. However, it didn't definitively rule out competing theories. Also, the group only looked at sprinklers with S-shaped arms. So this latest paper builds on that earlier work by extending the experiments to silly sprinklers the team created themselves. Ristroph et al. tested them in both forward mode (where water sprays out) and reverse mode (where water is sucked in).

Their observations strongly supported Ristroph et al.'s momentum flux theory and were inconsistent with both Mach's and Feynman's hypotheses. They also found that the arm shape of a given sprinkler can control the jet flow, and the team devised specific guidelines for designing structures to control flow to produce torque and rotation. “Our findings provide a firmer understanding of how components respond to fluid flows—knowledge that can guide future engineering and technological advances for devices, such as turbines, that convert these flows into energy,” said co-author Brennan Sprinkle of the Colorado School of Mines.

Ristroph’s lab frequently addresses these kinds of colorful real-world puzzles. For instance, in 2018, Ristroph and colleagues fine-tuned the recipe for the perfect bubble based on experiments with soapy thin films.  In 2021, the Ristroph lab looked into the formation processes underlying so-called “stone forests” common in certain regions of China and Madagascar. In 2021, his lab built a working Tesla valve, in accordance with the inventor’s design, and measured the flow of water through the valve in both directions at various pressures. And in 2022, Ristroph studied the surpassingly complex aerodynamics of what makes a good paper airplane—specifically what is needed for smooth gliding.

PNAS, 2026. DOI: 10.1073/pnas.2537479123 (About DOIs).

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The same question drives both the plot of Moana and decades of archaeological research: Why, after centuries of relative stability, did Polynesian voyagers suddenly begin settling islands thousands of kilometers away across the Pacific?

The latest Moana movie is a live-action adaptation of a Disney animated movie of the same name. While the films are fictional, they draw inspiration from the rich seafaring heritage of Polynesian peoples, whose ancestors undertook one of the greatest episodes of maritime exploration in human history.

New climate evidence may help us understand why they embarked on these voyages.

The backdrop to Moana is the mystery of the “long pause”. This was a period when Polynesian ancestors, the Lapita people, sailed east into the Pacific as far as the island archipelagos of Samoa and Tonga, arriving around 3,000 years ago. They brought with them distinct pottery styles and an island-based culture.

Human migrations into the Pacific:

Ancestral Polynesians only moved beyond Samoa and Tonga after a 1,700-year "long pause." The remaining island archipelagos were then settled rapidly. Credit: David Sear

Yet, for the next 1,700 years, there was little voyaging further east. Archaeological evidence suggests that populations in Tonga and Samoa grew and developed their own distinct post-Lapita culture.

Then, between 900 and 1100 AD, ancestral Polynesians suddenly undertook a massive phase of eastward migration. Over the next century, voyagers in huge double-hulled sailing canoes reached Hawaii, Aotearoa (New Zealand), and Rapa Nui (Easter Island). The spread of sweet potatoes around Pacific islands indicates they probably made contact with the continental Americas too.

When European navigators finally arrived centuries later, they were astonished to find even the smallest atolls peopled by communities sharing deep cultural and linguistic commonalities.

The mystery of the "long pause"

For generations, anthropologists and historians have debated what ended the long pause. Was it new sailing technology able to combat the easterly trade winds? Was it driven by social pressures and growing populations? Or was there a physical, environmental catalyst behind their choice?

To answer this, we have to look at the physical factors that make survival on a Pacific island possible: fresh water and food. As populations grow, resource demands intensify.

While ancestral Polynesians were highly adaptable and accustomed to seasonal droughts, prolonged and severe droughts during times of high population density might mean an island could no longer support its human population. Ultimately, island survival hinges on a single critical resource: rainfall.

Unlocking the climate record

Until recently, scientists lacked evidence from the Tonga and Samoa region of what the climate was like in this critical migration era. But we were able to reconstruct these past changes by analyzing hydrogen isotopes—slightly different forms of the same element—preserved in ancient mud from swamps and lakes.

In the tropics, the isotopic composition of rainwater reflects the amount of rainfall. As algae and plants grow and absorb this water, they lock this chemical signature into molecules that can survive in sediment for thousands of years, providing a natural archive of past rainfall.

Using this technique, we found evidence of a sustained, severe dry period in the southwest tropical Pacific between 850 and 1200 AD. Our results, recently published in the Journal of Pacific Archaeology, indicate this was the driest period the region had experienced in the past 2,000 years. Crucially, this drought coincided with a time when island populations were larger.

The great migration into the eastern Pacific coincided with a dry climate in the western Pacific:

Humans mostly arrived in the eastern Pacific soon after a dry period (marked orange) of long-term climate conditions further west (top graph) and a series of sudden ‘dry shocks’ (marked orange, in the middle graph). Credit: David Sear

Why would some islands experience a decades or centuries-long drought? Rainfall in the tropical South Pacific depends on the position of the South Pacific Convergence Zone, or SPCZ, a major belt of clouds and rain that shifts east and west over time, driven by patterns of sea surface temperature. Short-term shifts are linked to El Niño and La Niña, but the SPCZ can also move over much longer timescales, bringing decades of unusually dry or wet conditions to different parts of the Pacific.

All this matches up with genetic data that indicates Samoa’s population rapidly increased around 1000 AD, perhaps thanks to the arrival of new people. This suggests several factors aligned—severe climate stress, expanding populations, better canoe technology—to prompt daring exploration eastward.

The story of Polynesian expansion is remarkable in its own right. As Moana introduces new audiences to Pacific voyaging traditions, scientists are continuing to deepen our understanding of the environmental challenges these extraordinary navigators faced—and how they responded with ingenuity, resilience and exploration on an oceanic scale.

David Sear, Professor in Physical Geography, University of Southampton; Manoj Joshi, Professor of Climate Dynamics, University of East Anglia, and Mark Peaple, Research Fellow, Palaeoclimate, University of Southampton. This article is republished from The Conversation under a Creative Commons license. Read the original article.

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WD 1856 b is the only confirmed case of a planet that survived the death of a Sun-like star. It’s a Jupiter-size world orbiting a white dwarf—the burned-out remnant of a Sun-like star. Now, a team of astronomers has used the James Webb Space Telescope to take a closer look at this planet for the first time, and what they found makes an already strange system even stranger.

A feeding frenzy

WD 1856 b was an accidental discovery. Astronomers pointed the TESS observatory at a sample of roughly 2,000 white dwarfs in 2020. These stars are the remains of a Sun-like star that have already gone through a red-giant phase, leaving behind an Earth-size body that’s primarily composed of elements like carbon and oxygen. The TESS team was searching for small objects like comets or asteroids that might transit across the face of these dead stars.

What they found in the WD 1856 system was a gas giant. “As soon as they looked at it, they said, okay, that’s weird,” said Christopher O’Connor, a theoretical astrophysicist at Cornell University and co-author of the recent Nature study on WD 1856 b.

The white dwarf is about seven times smaller than the gas giant circling around it. Its brightness should be dropping to nearly nothing each time the planet crosses in front of it, but instead it’s dipping by about half. O’Connor thinks the reason is a grazing transit, where only the edge of the planetary disk clips the face of the star. “That’s a very unlikely viewing angle,” he said, “but it’s the only way to explain what we actually see.”

What’s more, the planet orbits at about 0.02 AU from the white dwarf, which goes against our ideas of how the death of a star should reshape its system. “When the star expands to become a red giant, it consumes the inner planets,” O’Connor explains. Then, in the process of shrinking down to a white dwarf, it loses about half of its original mass, which means its gravitational pull becomes weaker. “The outer planets, like gas giants, should migrate outward by about a factor of two,” O’Connor said.

WD 1856 b, though, apparently did not migrate outward. It got closer.

The discovery immediately has the science community buzzing. “It sent theoretical astrophysicists into a feeding frenzy,” O’Connor said. “When you find something that’s totally bizarre, totally in the wrong place, totally unexpected from any previous way of thinking about things—that’s the Universe inviting us to get creative.” First, though, scientists needed more data to get creative with, so O’Connor’s team booked time on the James Webb Space Telescope to take a closer look at what was going on in the WD 1856 system.

Eight minutes of light

The JWST observations were done on April 27, 2023, and captured a single transit that lasted just eight minutes. The viewing angle and the unusual size mismatch between the star and its planet posed an immediate technical problem. Standard exoplanet transmission spectroscopy assumes a smaller planet is entirely silhouetted against the face of a much larger star, which was not the case here.

To get around it, the team developed new equations to express the transmission spectrum as the time-varying area of the planet overlapping the star’s disk. Then, they modified POSEIDON, software for reconstructing exoplanets’ atmospheres based on JWST data to account for the grazing transit geometry (the software had been developed by Ryan MacDonald, the lead author of the study). When the scientists were done crunching numbers, WD 1856 b’s atmosphere proved somewhat surprising.

It turned out the planet is shrouded in aerosol hazes, and its atmosphere contains methane. It is also far hotter than the team expected. WD 1856 b apparently emits roughly 25 times more energy into space than it receives from its cooling host star. Even though its star, according to O’Connor, has been dead for about 6 billion years, the planet is glowing.

This extraordinary temperature, O’Connor argues, tells us a lot about WD 1856 b’s history.

Running hot

“We expected this planet to be roughly as hot as Jupiter, but it wasn’t,” O’Connor said. At about 0.02 AU from a white dwarf that has been cooling for 6 billion years, WD 1856 b should be somewhere between 150 and 200 Kelvin, close to the temperature of Jupiter’s cloud tops. Instead, it is around 400 Kelvin. “Whatever is causing this planet to glow, it must be an internally derived heat rather than just re-radiating energy from the star,” O’Connor said.

The planet, according to the team, cannot be radiating warmth left over from its formation. Something must have heated it at some point. Working backward through planetary cooling models, the team managed to estimate when it happened. Doing so, the scientists figured out the most probable reason why WD 1856 b got so close to its star.

The team initially came up with two competing scenarios to explain how WD 1856 b ended up in its current orbit. The first is a common-envelope model, in which the planet was originally in a close orbit and survived being engulfed when its star expanded into a red giant, emerging from the stellar envelope hot and tight against the remnant core. In the second, a high-eccentricity migration model, the planet started farther out, had its orbit destabilized by gravitational interactions with companion objects (WD 1856 has two distant stellar companions) and then spiraled inward over billions of years through a sequence of highly eccentric plunges.

One of the points at which these two scenarios differ is timing. Common-envelope evolution concludes when the star finishes its red giant phase, in this case roughly 5.4 billion years ago. High-eccentricity migration could deliver a planet to its current orbit billions of years later.

Running the planet’s current temperature backward through their cooling models, the team found that the reheating event most likely occurred 3 billion to 5.5 billion years after the end of the red giant phase—far too late for the common-envelope scenario. “We interpret the planet’s temperature as residual heat from its migration process,” O’Connor said. “And we think the timing is such that it can only have been through gravitational interactions with the companion stars.”

But this explanation comes with a caveat.

Search for survivors

The cooling models used in the calculation were built for objects with Jupiter-like atmospheric compositions, where methane accounts for roughly 0.3 percent of the atmosphere. On WD 1856 b, the methane content stands at roughly 7 percent. Because methane is a very potent greenhouse gas, this discrepancy might have skewed the models’ predictions. O’Connor says building new models of objects with atmospheric compositions closer to those of WD 1856 b might be necessary to ensure we have the evolution of the survivor planet right. “That’s going to take a pretty dedicated effort,” he said. Efforts like this, though, might soon pay off.

WD 1856 is only about 75 light-years from Earth—it’s practically our galactic neighbor. O’Connor takes the proximity as a hint that there might be more planets that outlived their stars out there. “Having one so close to us is a suggestion that there might be a lot more of these waiting to be found,” he said. Before embarking on the wide search for planetary survivors, though, the team wants to examine the WD 1856 system in more detail.

“We’ve already taken additional James Webb Telescope observations of this system. Those happened long after we submitted this paper. Our team has only really just started,” O’Connor said.

Nature, 2026. DOI: 10.1038/s41586-026-10514-7

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