Presentation #320.02 in the session Asteroid Dynamics (iPosters).
Data Release 3 was published in June 2022 and contains ultra-precise astrometric measurements for 158,152 asteroids (Tanga et al. 2022, A&A). This release contains a longer observational arc and more data points which are essential in detecting faint non-gravitational forces, such as the Yarkovsky effect (A2 or da/dt). Among Near-Earth Asteroids (NEA), there are many objects with confirmed Yarkovsky effect values. However, this effect still remains hard to detect especially for further and greater objects in the Main Belt.
In Figure 1 we present the histogram of the Gaia DR3 asteroid’s diameters. In Gaia DR3 there are 446 NEA (including 93 Potentially Hazardous Objects) where 428 of them are sub-5 km objects.
The impact of Gaia data in the determination of the Yarkovsky effect has already been proven (Spoto et al. 2018, A&A, 616, A13; Spoto et al. 2019, EPSC-DPS Joint Meeting (p. 182); Dziadura et al. 2022, Icarus, 115040; Tanga et al. 2022, A&A).
We present preliminary results of A2 parameter obtained with Gaia DR3. We compare the A2 value determined using OrbFit and Gaia DR3 with the expected value of the studied objects, determined as in Spoto et al. (2015, Icarus, 257, 275-289) and Del Vigna et al. (2018, A&A, 617, A61). We used the new weighting scheme (Spoto et al., in preparation).
We introduce the fragment of results in Fig. 2. The Yarkovsky effect was determined for selected objects available in Gaia DR3 (606 objects). The S value represents S = A2(this work)/A2(expected). There are 15 asteroids which meet the conditions of S > 2 and SNR > 3 (green), which is more than when using Gaia DR2.
Acknowledgements: This work presents results from the European Space Agency (ESA) space mission Gaia. Gaia data are being processed by the Gaia Data Processing and Analysis Consortium (DPAC). Funding for the DPAC is provided by national institutions, in particular the institutions participating in the Gaia MultiLateral Agreement (MLA). The Gaia mission website is https://www.cosmos.esa.int/gaia. The Gaia archive website is https://archives.esac.esa.int/gaia. The research leading to these results has received funding from the Ministry of Science and Higher Education of Poland in the years 2018/2022, as a research project under the ‘‘Diamond Grant” program, grant number 0062/DIA/2018/47.