A multi-epoch search for distant Solar System bodies in the Catalina Sky Survey
Year: 2026
Type: article
Abstract: Wide-field astronomical surveys have significantly expanded the population of known trans-Neptunian objects. However, detecting very distant bodies remains challenging due to their extremely slow apparent motion and faint magnitudes. Multi-epoch transient surveys provide an opportunity to identify such objects by exploiting the positional consistency in observations obtained on different nights. We developed and validated an automated detection pipeline to search archival multi-epoch survey data for faint, slow-moving bodies in the outer Solar System, and we assessed its potential for discovering previously unknown distant objects. We applied our pipeline to observations from the Catalina Sky Survey (CSS), analysing repeated images of the same sky regions obtained over multiple nights. The algorithm identifies candidate objects based on positional consistency and motion across epochs. Its performance was evaluated through recovery tests using catalogued objects and synthetic sources injected into the images, allowing us to quantify the detection efficiency as a function of apparent magnitude. The pipeline successfully recovered the distant trans-Neptunian objects Sedna and Eris in blind tests where prior catalogue information was disabled. The recovery fraction of catalogued objects approaches 100$%$ for objects brighter than 19.5 mag in the V band, while the synthetic-source recovery efficiency is approximately 90$%$ for objects brighter than 20.5 mag in the Gaia G band and decreases to approximately 54$%$ in the G=21.0--21.5 magnitude bin under the observational conditions of the CSS. The analysis also resulted in the serendipitous detection of Sycorax, an irregular satellite of Uranus. In addition, two previously unknown distant Solar System objects, 2020 TZ114 and 2022 BO71, were identified and later designated by the Minor Planet Center. The results demonstrate that multi-epoch motion-based detection strategies applied to archival survey data provide an effective approach for identifying faint and distant Solar System bodies. Similar methods applied to current and future wide-field surveys, such as the Vera C. Rubin Observatory Legacy Survey of Space and Time, have substantial potential to expand the census of the outer Solar System.
Source: Astronomy and Astrophysics
Language: English
Topic: Astro and Planetary Science
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,865
OpenAlex ID: W7223092271