Research Information System
[Europlanet Science Congress 2022], Granada, Spain, 18 - 23 September 2024, vol.16, pp.172
Centaurs and trans-Neptunian objects (TNOs) are considered to be among the most pristine members of our solar system and carry plenty of information on the physical and dynamical processes that shaped our solar system.
Here we report the occultation observation of the star Gaia EDR3 133768513079427328 (G: 11.7 mag, R: 11.3 mag) by the TNO (119951) 2002 TC302 on November 11, 2021. The shadow path was predicted to cross central Europe and USA. We received a total of 57 observations reports, with at least 19 positive detections and 25 miss reports (no event detected).
2002 TC302 is a high-inclination (i ~ 35°) TNO in a 2:5 resonance with Neptune, orbiting the Sun in an average distance of about 55 au. The radiometric diameter from Herschel and Spitzer thermal observations is 584.1 (+106.5, -88.0) km [1], while the analysis of a multi-chord stellar occultation observed on 28 January 2018, combined with light curve data, revealed an area-equivalent diameter of 499.6 ± 10.2 km [2]. From our preliminary elliptical profile fit of the 11 November 2021 occultation observations we derived a projected area-equivalent diameter of 500.3 ± 2.5 km, which is consistent with the above mentioned value from the previous stellar occultation in 2018. The 2018 and 2021 occultation diameters are significant (about 84 km) smaller than the radiometric diameter, which might be even larger (D ~ 643 km) after a reanalysis of the Herschel data [3]. This discrepancy might indicate the existence of an unresolved satellite, but other possibilities are being considered as well [see also 2,3].