Using preliminary data from the Simonyi Survey Telescope at the NSF–DOE Vera C. Rubin Observatory, scientists have discovered over 11,000 new asteroids in our solar system. The findings were confirmed by the International Astronomical Union’s Minor Planet Center (), and include hundreds of distant worlds beyond Neptune as well as 33 previously unknown near-Earth objects.

The discoveries — Rubin Observatory’s largest asteroid haul yet — were made using data from the observatory’s early optimization surveys and processed with software developed at the ����Ӱ�Ӵ�ý’s . The new findings are a powerful preview of the observatory’s transformative impact on solar system science.

“This first large submission after is just the tip of the iceberg and shows that the observatory is ready,” said , a UW professor of astronomy and leader of Rubin’s solar system team, which is located at the UW. “What used to take years or decades to discover, Rubin will unearth in months. We are beginning to deliver on Rubin’s promise to fundamentally reshape our inventory of the solar system and open the door to discoveries we haven’t yet imagined.”

The submission to MPC comprises approximately 1 million observations, taken over the span of a month and a half, of over 11,000 new asteroids and more than 80,000 already known asteroids, including some that had previously been observed but were later “lost” because their orbits were too uncertain to predict their future locations. The new batch adds to roughly 1,500 asteroids previously discovered by Rubin as part of its First Look project.

The newly discovered near-Earth objects, or NEOs, are small asteroids and comets whose closest approach to the sun is less than 1.3 times the distance between Earth and the sun. None of the new NEOs pose a threat to Earth. Once in full operation, Rubin is expected to reveal an additional nearly 90,000 new NEOs, some of which may be potentially hazardous. By enabling early detection and continuous monitoring of these objects, Rubin will be a powerful tool for planetary defense.

The dataset also contains roughly 380 trans-Neptunian objects (TNOs) — icy bodies orbiting beyond Neptune. Two of the newly discovered TNOs — provisionally named and — have been found to be on extremely large and elongated orbits. At their most distant points, these two objects reach roughly 1,000 times farther away from the sun than the Earth is, placing them among the 30 most distant known asteroids.

A total of 12,700 asteroids discovered with Rubin are shown here during the 1.6 years of observation. The discoveries come in three bursts: 73 were discovered during the first early test observations using Rubin’s Commissioning Camera in late 2024; 1,514 were discovered during First Look observations in April and May 2025; and the recent 11,000 asteroids were discovered in Rubin’s early optimization surveys in Summer 2025.

The discoveries were enabled by Rubin Observatory’s unique combination of a large mirror, the world’s most powerful astronomical digital camera, and highly sophisticated, software-driven pipelines developed at the UW that can detect faint, fast-moving objects against a crowded sky. These capabilities will allow Rubin to build the most detailed census of our solar system ever, and the resulting discoveries will help scientists work out the story of the solar system’s history.

“Rubin’s unique observing cadence required a whole new software architecture for asteroid discovery,” said , a UW research scientist of astronomy who, together with UW astronomy graduate student , built the software that detected them. “We built it, and it works. It seems pretty clear this observatory will revolutionize our knowledge of the asteroid belt.”

Particularly striking is the rapid growth of the TNO population. The 380 candidates discovered by Rubin in less than two months adds to the 5,000 discovered over the past three decades. As with less distant asteroids, finding the TNOs depended critically on developing new sophisticated algorithms.

“Searching for a TNO is like searching for a needle in a field of haystacks — out of millions of flickering sources in the sky, teaching a computer to sift through billions of combinations and identify those that are likely to be distant worlds in our solar system required novel algorithmic approaches,” said , a senior astrophysicist at the Harvard & Smithsonian Center for Astrophysics and former director of the Minor Planet Center, who spearheaded the work on the TNO discovery pipeline.

“Objects like these offer a tantalizing probe of the solar system’s outermost reaches, from telling us how the planets moved early on in the solar system’s history, to whether a hitherto undiscovered ninth large planet may still be out there,” said , a research scientist at the Harvard-Smithsonian Center for Astrophysics who, with Holman, developed the algorithms to detect distant solar system objects with Rubin data.

The verification of this large group of discoveries enables the entire global community to access the data, refine orbits and begin analysis immediately. And these 11,000-some asteroids are just the start. Once the decade-long Legacy Survey of Space and Time () begins later this year, scientists expect Rubin to discover this many asteroids every two to three nights during the early years of the survey. This will ultimately triple the number of known asteroids and increase the number of known TNOs by nearly an order of magnitude.

Rubin Observatory is jointly operated by NSF NOIRLab and SLAC.

For more information, contact Jurić at mjuric@uw.edu.��

This story was adapted from a .

Operations of the Vera C. Rubin Observatory are funded by the U.S. National Science Foundation and the U.S. Department of Energy’s Office of Science.

Other team members include , a former DiRAC postdoctoral fellow at the UW, now at the Institute for Astronomy, Geophysics and Atmospheric Sciences of the University of São Paulo; , a UW research software engineer and B612 Asteroid Institute team member who earned his doctorate in astronomy at the UW; , a former UW postdoctoral researcher in astronomy, now at the University of Illinois Urbana-Champagne; and at Princeton University.

was combing through old telescope data from 2020 when he found an otherwise boring star acting very strangely. The star, named Gaia20ehk, was about 11,000 light-years from Earth near . It was a stable “main sequence” star, much like our sun, which meant that it should emit steady, predictable light. Yet this star began to flicker wildly.

“The star’s light output was nice and flat, but starting in 2016 it had these three dips in brightness. And then, right around 2021, it went completely bonkers,” said Tzanidakis, a doctoral candidate in astronomy at the ����Ӱ�Ӵ�ý. “I can’t emphasize enough that stars like our sun don’t do that. So when we saw this one, we were like ‘Hello, what’s going on here?’”

The cause of the flickering had nothing to do with the star itself: Huge quantities of rocks and dust — seemingly from out of nowhere — were passing in front of the distant star as the material orbited the system, patchily dimming the light that reached Earth. The likely source of all that debris was even more remarkable: a catastrophic collision between two planets.

“It’s incredible that various telescopes caught this impact in real time,” Tzanidakis said. “There are only a few other planetary collisions of any kind on record, and none that bear so many similarities to the impact that created the Earth and moon. If we can observe more moments like this elsewhere in the galaxy, it will teach us lots about the formation of our world.”

in The Astrophysical Journal Letters.

Planets form when gravity forces together matter — dust, gas, ice or rocky debris, for example — orbiting a new star. Early solar systems are chaotic — planets routinely collide and explode or go flying off into outer space. Through this process, and over perhaps 100 million years, solar systems like ours winnow their planets down and settle into an equilibrium.��

As common as these collisions probably are, observing one in a distant solar system requires patience and luck. The orbits of the planets must take them directly between us and their star, so that the resulting debris obscures some of the star’s light. The telltale flicker then takes years to play out.��

“Andy’s unique work leverages decades of data to find things that are happening slowly — astronomy stories that play out over the course of a decade,” said senior author , a UW assistant research professor of astronomy. “Not many researchers are looking for phenomena in this way, which means that all kinds of discoveries are potentially up for grabs.”

Tzanidakis, the study’s lead author, studies extreme variability in stars over time. His previous work at the UW identified a system with a binary star and a large dust cloud that caused a seven-year eclipse.

The behavior of Gaia20ehk, however, posed a new mystery. The star’s particular fluctuation — short dips in brightness and then chaos — had never before been observed. The team was stumped, until Davenport suggested that they use data from a different telescope to look for infrared light rather than visible light.��

“The infrared light curve was the complete opposite of the visible light,” Tzanidakis said. “As the visible light began to flicker and dim, the infrared light spiked. Which could mean that the material blocking the star is hot — so hot that it’s glowing in the infrared.”

A cataclysmic collision between planets would certainly produce enough heat to explain the infrared energy. What’s more, the right kind of collision could also explain those initial dips in light.

“That could be caused by the two planets spiraling closer and closer to each other,” Tzanidakis said. “At first, they had a series of grazing impacts, which wouldn’t produce a lot of infrared energy. Then, they had their big catastrophic collision, and the infrared really ramped up.” 

There are also clues that the collision resembles the one that created the Earth and moon . The dust cloud is orbiting Gaia20ehk at roughly one astronomical unit, the same distance from the sun to the Earth. At that distance, the material could eventually cool down enough to solidify into something similar to our Earth-moon system. Scientists like Tzanidakis and Davenport can’t know for sure until the dust settles — literally — in the system. That could take a few years, or a few million.��

In the meantime, their discovery is a call to action to find more collisions. The powerful Simonyi Survey Telescope at the NSF–DOE Vera C. Rubin Observatory will be well suited to the task when it begins its later this year; some back-of-the-napkin math by Davenport suggests that Rubin could find 100 new impacts over the next 10 years. That could ultimately help narrow the search for habitable worlds outside our solar system.

“How rare is the event that created the Earth and moon? That question is fundamental to astrobiology,” Davenport said. “It seems like the moon is one of the magical ingredients that makes the Earth a good place for life. It can help shield Earth from some asteroids, it produces ocean tides and weather that allow chemistry and biology to mix globally, and it may even play a role in driving tectonic plate activity. Right now, we don’t know how common these dynamics are. But if we catch more of these collisions, we’ll start to figure it out.”

For more information, contact Tzanidakis at atzanida@uw.edu and Davenport at jrad@uw.edu.

This research was funded by Breakthrough Initiatives.

On Feb. 24, astronomers’ computers around the world lit up with a deluge of cosmic notifications — 800,000 alerts about new asteroids in our solar system, exploding stars across the galaxy and other noteworthy changes in the night sky. The discoveries were made by the Simonyi Survey Telescope at the in Chile and distributed globally within about two minutes.

That flurry of notifications marked the commencement of the observatory’s Alert Production Pipeline, a sophisticated software system developed at the ����Ӱ�Ӵ�ý that is eventually expected to produce up to seven million alerts per night.

“Rubin’s alert system was designed to allow anyone to identify interesting astronomical events with enough notice to rapidly obtain time-critical follow-up observations,” said , a research associate professor of astronomy at the UW who leads the Alert Production Pipeline Group for the Rubin Observatory. “Rubin will survey the sky at an unprecedented scale and allow us to find the most rare and unusual objects in the universe. We can’t wait to see the exciting science that comes from these data.”

The beginning of scientific alerts is one of the last major milestones before Rubin Observatory launches its (LSST) later this year. During the LSST, Rubin will scan the Southern Hemisphere sky nightly for 10 years to precisely capture every visible change using . These alerts will chronicle the treasure trove of scientific discoveries that Rubin will make through its time-lapse record of the universe. In the first year of the LSST, Rubin is expected to capture images of more objects than all other optical observatories combined in human history.

The UW played a central role in the software that enabled this month’s milestone. The alert pipeline was developed by a team of about two dozen researchers and software developers in the astronomy department’s . The team has spent the past decade working with other data management teams around the country to figure out how to process the staggering 10 terabytes of images that Rubin produces every night, and will continue to develop and operate the alert system throughout the 10-year LSST survey.

“Enabling real-time discovery on such a massive data stream has required years of technical innovation in image processing algorithms, databases and data orchestration. We’re thrilled to continue the UW’s legacy of excellence in data-driven science.” Bellm said.

While the night sky seems calm and unchanging to the casual viewer, it’s actually alive with motion and transformation. Each alert signals something that has changed in the sky since Rubin last looked — a new source of light, a star that brightened or dimmed, or an object that moved. With Rubin’s alerts, scientists will have a greater ability to catch supernovae in their earliest moments, discover and track asteroids to assess potential threats to Earth and spot rare interstellar objects as they race through the solar system.

Scientists can use these data to better understand the nature of dark matter, dark energy and other unknown aspects of the universe.

“The discoveries reported in these alerts reflect the power of NSF-DOE Rubin Observatory as a tool for astrophysics and the importance of sustained federal support,” said Kathy Turner, program manager in the High Energy Physics program in the U.S. Department of Energy’s . “Rubin Observatory’s groundbreaking capabilities are revealing untold astrophysical treasures and expanding scientists’ access to the ever-changing cosmos.”

Every 40 seconds during nighttime observations, Rubin captures a new region of the sky. It then sends the data on a seconds-long journey from Chile to the U.S. Data Facility (USDF) at the in California for initial processing. Rubin’s data management system automatically compares it to a template made from previous images of the same region. This comparison allows it to detect the slightest variations. With every change, such as the appearance of a new point of light, an object’s movement or a change in brightness, the system generates a public alert within two minutes.

“The scale and speed of the alerts are unprecedented,” says Hsin-Fang Chiang, a SLAC software developer leading operations for data processing at the USDF. “After generating hundreds of thousands of test alerts in the last few months, we are now able to say, within minutes, with each image, ‘Here is everything. Go.’”

Rubin’s alerts are public, meaning anyone — from professional researchers to students and citizen scientists — can access and explore them. The speed of the alerts allows scientists using other ground- and space-based telescopes around the world to coordinate follow-up observations. This collaboration will enable fast and detailed studies of unfolding phenomena.��

Additionally, through collaborations with platforms like , Rubin will empower the global community to help classify cosmic events and contribute directly to discovery.

Rubin Observatory is jointly operated by NSF and SLAC.

For more information, contact Bellm at ecbellm@uw.edu.

This story was adapted from a press release by and .

Operations of the Vera C. Rubin Observatory are funded by the U.S. National Science Foundation and the U.S. Department of Energy’s Office of Science.