Geldonia is a member the Eos family (606),[4] the largest asteroid family of the outer main belt consisting of nearly 10,000 asteroids.[12]: 23 It orbits the Sun at a distance of 2.9–3.1 AU once every 5 years and 3 months (1,915 days). Its orbit has an eccentricity of 0.03 and an inclination of 9° with respect to the ecliptic.[1]
The body's observation arc begins with its first identification as A921 TF at Heidelberg Observatory in October 1921, almost 10 years prior to its official discovery observation at Uccle.[11]
In November 2010, a rotational lightcurve of Geldonia was obtained from photometric observations by Italian astronomer Silvano Casulli. Lightcurve analysis gave a longer-than-average rotation period of 28.3 hours with a brightness amplitude of 0.11 magnitude (U=2-). While not being a slow rotator, which have periods longer than 100 hours, Geldonia's spin rate is still longer than that of most minor planets, which typically rotate between 2 and 20 hours once around their axis.
^ abcdUsui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. (online, AcuA catalog p. 153)