Discovered by M. F. Wolf MPC designation 1134 Kepler Minor planet category Mars-crosser Discovered 25 September 1929 Discoverer Max Wolf Asteroid group Mars-crosser asteroid | Discovery date 25 September 1929 Alternative names 1929 SA · 1951 SA Observation arc 86.62 yr (31,638 days) Orbits Sun Named after Johannes Kepler | |
Discovery site Landessternwarte Heidelberg-Königstuhl Similar 528 Rezia, 1111 Reinmuthia, 417 Suevia, 540 Rosamunde, Sun | ||
1134 Kepler, provisional designation 1929 SA, is a stony asteroid and eccentric Mars-crosser from the asteroid belt, approximately 4 kilometers in diameter. It was discovered on 25 September 1929, by German astronomer Max Wolf at Heidelberg Observatory in southwest Germany. It is named after Johannes Kepler.
Description
In the SMASS taxonomy, Kepler is a stony S-type asteroid. It orbits the Sun at a distance of 1.4–3.9 AU once every 4 years and 5 months (1,601 days). Its orbit has an eccentricity of 0.47 and an inclination of 15° with respect to the ecliptic. The body's observation arc begins at Heidelberg, the night after its official discovery observation.
Kepler's diameter has not been estimated by any of the prominent space-based surveys such as the Infrared Astronomical Satellite IRAS (1982), the Japanese Akari satellite (2006), NASA's Wide-field Infrared Survey Explorer (2009) or its subsequent NEOWISE mission (2013). Based on a generic magnitude-to-diameter conversion, Kepler's diameter is between 3 and 8 kilometer for an absolute magnitude of 14.2 and an assumed albedo in the range of 0.25 to 0.05. Since its spectral type falls into the class of stony asteroids, which have an averaged standard albedo around 0.20, Kepler's generic diameter is close to 4 kilometers, as the higher a body's albedo (reflectivity), the shorter its diameter at a fixed absolute magnitude (brightness).
As of 2017, Kepler's rotation period and shape remain unknown, which is rather unusual, as 1457 out of the first 1500 low-numbered minor planets have a least an estimated period.
This minor planet was named on the commemoration of the 300th death anniversary of astronomer Johannes Kepler (1571–1630), best known for his laws of planetary motion. Kepler is also honored by a lunar and Martian crater, by Kepler Dorsum – a mountain ridge on the Martian moon Phobos, and by Kepler's Supernova. Naming citation was first published in 1930, in the astronomy journal Astronomical Notes (AN 240, 135). The space observatory Kepler and its many discovered exoplanets also bear his name (see also Kepler (disambiguation)).