An international team of astronomers, including researchers from the University of Washington and Queen’s University Belfast, has announced that the forthcoming Vera C. rubin Observatory is expected to detect millions of previously unkown objects in our solar system.

The NSF-DOE Vera C. Rubin Observatory is poised to transform our comprehension of the solar system’s “small bodies,” encompassing asteroids, comets, and other minor planets.

Located on the Cerro Pachón ridge in northern Chile, the Rubin Observatory boasts the 8.4-meter Simonyi Survey Telescope, uniquely designed with three mirrors to survey the entire visible sky every few nights. Its centerpiece is the 3.2 gigapixel legacy Survey of Space and Time (LSST) Camera, the world’s largest digital camera, which captures a 9.6 square-degree field of view through six filters-approximately 45 times the area of the full moon. This “wide-fast-deep” system will generate 20 terabytes of data nightly, creating an unprecedented time-lapse “movie” of the cosmos over the next decade, and a powerful dataset for mapping the solar system.

The team, spearheaded by Meg Schwamb of Queen’s University, developed Sorcha, an innovative open-source software to forecast potential discoveries.Sorcha is the first simulator to utilize Rubin’s planned observing schedule,applying assumptions about how the Rubin Observatory detects astronomical sources in its images,based on the best current models of the solar system.

“Accurate simulation software like Sorcha is critical,” saeid Schwamb, a reader in the School of Mathematics and Physics at Queen’s University. “It tells us what Rubin will discover and lets us know how to interpret it. Our knowledge of what objects fill Earth’s solar system is about to expand exponentially and rapidly.”

Beyond the eight major planets, the solar system hosts a vast population of small bodies formed alongside the planets over 4.5 billion years ago. many of these bodies remain largely unchanged as the solar system’s inception, serving as a fossil record of its earliest days. By examining their orbits, sizes, and compositions, astronomers can reconstruct how planets formed, migrated, and evolved.

these objects-numbering in the tens of millions-offer insights into processes such as the delivery of water and organic material to Earth, the reshaping of planetary orbits by giant planets, and the ongoing risk posed by objects whose paths bring them close to our planet.

The international team also includes researchers from the center for Astrophysics | Harvard & Smithsonian and the University of Illinois Urbana-Champaign.

A series of papers detailing the software and predictions have been accepted for publication by The Astronomical Journal.

The Rubin Observatory will observe these new small bodies multiple times using different optical filters, revealing their surface colors, unlike past surveys that typically used a single filter.

“With the LSST catalog of solar system objects, our work shows that it will be like going from black-and-white television to brilliant color,” said Joe Murtagh, a doctoral student at Queen’s University. “It’s very exciting — we expect that millions of new solar system objects will be detected and most of these will be picked up in the first few years of sky survey.”

The team’s simulations indicate that Rubin will map:

• 127,000 near-Earth objects-asteroids and comets whose orbits cross or approach Earth-more than tripling the currently known 38,000 objects and detecting over 70% of potentially hazardous bodies larger than 140 meters. This will reduce the risk of undetected asteroid impacts of catastrophic proportions by at least two times, substantially contributing to planetary defense.
• Over 5 million main-belt asteroids, up from about 1.4 million, with precise color and rotation data on roughly one in three asteroids within the survey’s first years, providing unprecedented insight into the characteristics and history of the solar system’s building blocks.
• 109,000 Jupiter Trojans, bodies sharing Jupiter’s orbit at stable “Lagrange” points-more than seven times the number cataloged today.These bodies represent some of the most pristine material dating back to the formation of the planets.
• 37,000 trans-Neptunian objects, residents of the distant Kuiper Belt-nearly 10 times the current census-shedding light on Neptune’s past migration and the outer solar system’s history.
• Approximately 1,500-2,000 Centaurs, bodies on short-lived giant planet-crossing orbits in the middle solar system. Most Centaurs will eventually be ejected from the solar system, but a few lucky ones will survive to become short-period comets. The LSST will provide the first detailed view of the Centaurs and the important transition stage from centaur to comet.

Mario Juric, a member of the Sorcha team and a UW professor of Astronomy, stated that the Rubin Observatory’s LSST offers a unique prospect to complete our picture of the solar system. Juric also is a team lead of Rubin’s Solar System processing Pipelines and a director of UW’s DiRAC Institute.

“Our simulations predict that Rubin will expand known small-body populations by factors of 4-9x, delivering an unprecedented trove of orbits, colors and light curves,” Juric said. “With this data, we’ll be able to update the textbooks of solar system formation and vastly improve our ability to spot — and potentially deflect — the asteroids that could threaten Earth.”

Jake Kurlander, a doctoral student at the UW, noted that it took 225 years of astronomical observations to detect the first 1.5 million asteroids, but Rubin will double that number in less than a year.

“Rubin’s unparalleled combination of breadth and depth make it a uniquely effective discovery machine,” Kurlander said.

Siegfried Eggl,an assistant professor of Aerospace Engineering at the University of Illinois Urbana-Champaign added: “only by debiasing LSST’s complex observing pattern can we turn raw detections into a true reflection of the solar system’s history — where the planets formed,and how they migrated over billions of years.Sorcha is a game changer in that respect.”

The Sorcha code is open-source and freely available with the simulated catalogs, animations at https://sorcha.space. By making these resources available, the Sorcha team has enabled researchers worldwide to refine their tools and be ready for the flood of LSST data that Rubin will generate, advancing the understanding of the small bodies that illuminate the solar system like never before.

The Rubin observatory is scheduled to unveil its first notable imagery at its “First Look” event on June 23, offering the world an early glimpse of the survey’s power.Full science operations are slated to begin later this year.