Using preliminary data from NSF–DOE Vera C. Rubin Observatory, scientists have discovered over 11,000 new asteroids. The data were confirmed by the International Astronomical Union’s Minor Planet Center (MPC), making this the largest single batch of asteroid discoveries submitted in the past year. The discoveries were made using data from Rubin’s early optimization surveys and offer a powerful preview of the observatory’s transformative impact on Solar System science.
Rubin Observatory is a joint program of NSF NOIRLab and DOE’s SLAC National Accelerator Laboratory, who cooperatively operate Rubin. NOIRLab is managed by the Association of Universities for Research in Astronomy (AURA).
The submission to MPC comprises approximately one 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. You can interact with all of Rubin’s asteroid discoveries in the Rubin Orbitviewer, which uses real data to provide an intuitive way to explore the structure of our cosmic backyard in three dimensions and in real time. Also, visit the Rubin Asteroid Discoveries Dashboard to learn about the new objects Rubin has uncovered.
“This first large submission after Rubin First Look is just the tip of the iceberg and shows that the observatory is ready,” says Mario Juric, faculty at the University of Washington and Rubin Solar System Lead Scientist. “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.”
Among the newly identified objects are 33 previously unknown near-Earth objects (NEOs), which 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 newly discovered NEOs pose a threat to Earth, and the largest is about 500 meters wide. Objects larger than 140 meters are closely tracked as they could cause significant regional damage if they impact, yet scientists estimate that only about 40% of these mid-sized NEOs have been identified so far.
Once operating fully in survey mode, Rubin is expected to reveal an additional nearly 90,000 new NEOs, some of which may be potentially hazardous, and to nearly double the number of known NEOs larger than 140 meters to around 70%. 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 2025 LS2 and 2025 MX348 — have been found to be on extremely large and elongated, or stretched out, orbits. At their most distant points, these two objects reach roughly 1000 times farther away from the Sun than the Earth is, placing them among the 30 most distant minor planets known.
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 designed to detect faint, fast-moving objects against a crowded sky. Rubin can survey the southern sky at roughly six times the sensitivity of most current asteroid searches, allowing it to detect smaller and more distant objects than ever before. These capabilities will allow Rubin to build the most detailed census of our Solar System ever, and all of the 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,” says Ari Heinze, University of Washington, who, together with Jacob Kurlander, a graduate student at the University of Washington, built the software that detected them. “We built it, and it works. Even with just early, engineering-quality data, Rubin discovered 11,000 asteroids and measured more precise orbits for tens of thousands more. 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 add to the 5000 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,” says Matthew Holman, a Senior Astrophysicist at the Center for Astrophysics | Harvard & Smithsonian 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 9th large planet may still be out there,” says Kevin Napier, 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 MPC’s 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 asteroids are just the start. Once the decade-long Legacy Survey of Space and Time (LSST) 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.
