On 7 October 1981, asteroid 88 Thisbe was observed to occult the 9th-magnitude star SAO 187124 from 12 sites. The timing of the different chords across the asteroid provided a diameter estimate of 232±12 km. This is 10% larger than the diameter estimate based on radiometric techniques.[8][9][10] During 2000, 88 Thisbe was observed by radar from the Arecibo Observatory. The return signal matched an effective diameter of 207 ± 22 km. This is consistent with the asteroid dimensions computed through other means.[11]
Photometric observations of this asteroid during 1977 gave a light curve with a period of 6.0422 ± 0.006 hours and a brightness variation of 0.19 in magnitude.[6]
Perturbation
Thisbe has been perturbed by asteroid 7 Iris and in 2001 Michalak estimated it to have a mass of 15×1018 kg.[5][a] But Iris is strongly perturbed by many minor planets such as 10 Hygiea and 15 Eunomia.[5]
In 2008, Baer estimated Thisbe to have a mass of 10.5×1018 kg.[4] In 2011 Baer revised this to 18.3×1018 kg with an uncertainty of 1.1×1018 kg.[4]
Notes
^ ab(Low mass estimate of Thisbe 0.074 / Mass of Ceres 4.75) * Mass of Ceres 9.43×1020 = 1.47×1019
References
^Noah Webster (1884). A Practical Dictionary of the English Language.
^ abcdeP. Vernazza et al. (2021) VLT/SPHERE imaging survey of the largest main-belt asteroids: Final results and synthesis. Astronomy & Astrophysics 54, A56
^ abSchober, H. J.; et al. (April 1979), "Photoelectric photometry and rotation periods of three large and dark asteroids - 49 Pales, 88 Thisbe and 92 Undina", Astronomy and Astrophysics Supplement Series, vol. 36, pp. 1–8, Bibcode:1979A&AS...36....1S.
^Taylor, G. E., "Progress in accurate determinations of diameters of minor planets", Asteroids, comets, meteors; Proceedings of the Meeting, Uppsala, Sweden, 20-22 June 1983, pp. 107–109, Bibcode:1983acm..proc..107T.