|Discovered by||A. Borrelly|
|Discovery date||5 February 1877|
|Epoch 31 July 2016 (JD 2457600.5)|
|Uncertainty parameter 0|
|Observation arc||133.62 yr (48806 d)|
|Aphelion||2.6525 AU (396.81 Gm)|
|Perihelion||2.1073 AU (315.25 Gm)|
|2.3799 AU (356.03 Gm)|
|3.67 yr (1341.0 d)|
|0° 16m 6.42s / day|
|Earth MOID||1.09593 AU (163.949 Gm)|
|Jupiter MOID||2.67257 AU (399.811 Gm)|
|27.417 h (1.1424 d)|
Baucis (minor planet designation: 172 Baucis) is a large main belt asteroid that was discovered by French astronomer Alphonse Borrelly on February 5, 1877, and named after a fictional character in the Greek legend of Baucis and Philemon. The adjectival form of the name is Baucidian. It is classified as an S-type asteroid based upon its spectrum.
Photometric observations of this asteroid from the southern hemisphere during 2003 gave a light curve that indicated a slow synodic rotation period of 27.417 ± 0.013 hours and a brightness variation of 0.25 in magnitude.
Polarimetric study of this asteroid reveals anomalous properties that suggests the regolith consists of a mixture of low and high albedo material. This may have been caused by fragmentation of an asteroid substrate with the spectral properties of CO3/CV3 carbonaceous chondrites.