1157 Arabia
1157 Arabia, provisional designation , is an asteroid from the outer regions of the asteroid belt, approximately 29 kilometers in diameter. Astronomer Karl Reinmuth discovered it at the Heidelberg Observatory in southwest Germany on 31 August 1929. The asteroid was named for the Arabian Peninsula. Orbit and classification Arabia is a non-family asteroid from the main belt's background population. It orbits the Sun in the outer asteroid belt at a distance of 2.7–3.6 AU once every 5 years and 8 months (2,073 days). Its orbit has an eccentricity of 0.14 and an inclination of 10° with respect to the ecliptic. The body's observation arc begins at Heidelberg in December 1930, more than a year after its official discovery observation. Physical characteristics Arabia is an assumed carbonaceous C-type asteroid, while the measured albedos are rather typical for a stony composition (see below). Rotation period In June 2008, Peter Caspari obtained a rotational lightcurve of Arabia from photometric observations at the BDI Observatory () near Sydney, Australia. Lightcurve analysis gave a rotation period of 15.225 hours with a brightness amplitude of 0.37 magnitude (). Diameter and albedo According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission