Gaia Data Release 2: Observations of solar system objects
Gaia Collaboration: F. Spoto, P. Tanga, F. Mignard, J. Berthier, B., Carry, A. Cellino, et al

TL;DR
Gaia DR2 provides high-precision astrometric and photometric data for over 14,000 solar system objects, enabling improved orbit determination and detection of subtle non-gravitational effects.
Contribution
This paper presents the processing, quality assessment, and scientific potential of Gaia DR2's solar system object observations, a significant advancement in asteroid astrometry.
Findings
Astrometric accuracy is below 1 mas for G~12-17 brightness range.
Data quality is consistent with the error model after accounting for uncertainty properties.
Preliminary tests show Gaia DR2 data enhances detection of non-gravitational effects on asteroids.
Abstract
The Gaia spacecraft of the European Space Agency (ESA) has been securing observations of solar system objects (SSOs) since the beginning of its operations. Gaia Data Release 2 (DR2) contains the observations of a selected sample of 14,099 SSOs. These asteroids have been already identified and have been numbered by the Minor Planet Center. Positions are provided for each Gaia observation at CCD level. As additional information, the apparent brightness of SSOs in the unfiltered G band is also provided for selected observations. We explain the processing of SSO data, and describe the criteria we used to select the sample published in Gaia DR2. We then explore the data set to assess its quality. To exploit the epoch astrometry of asteroids in Gaia DR2 it is necessary to take into account the unusual properties of the uncertainty, as the position information is nearly one-dimensional. When…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
