Discovered by A. Charlois MPC designation 398 Admete Observation arc 120.95 yr (44176 d) Orbits Sun Named after Admete (Greek mythology) Asteroid group Asteroid belt | Discovery date 28 December 1894 Minor planet category main-belt · (outer) Discovered 28 December 1894 Discoverer Auguste Charlois Discovery site Nice Observatory | |
Alternative names 1894 BN · 1951 LP
1952 QC1 · A907 RE Similar 441 Bathilde, 272 Antonia, 360 Carlova, 367 Amicitia, 276 Adelheid | ||
398 Admete, provisional designation 1894 BN, is a dark, carbonaceous asteroid from the outer region of the asteroid belt, about 47 kilometers in diameter. It was discovered on 28 December 1894, by French astronomer Auguste Charlois at Nice Observatory in southeastern France.
The dark C-type asteroid orbits the Sun at a distance of 2.1–3.4 AU once every 4 years and 6 months (1,656 days). Its orbit shows an eccentricity of 0.22 and is tilted by 10 degrees to the plane of the ecliptic. The body's surface has a low albedo of 0.06, which is a typical value for carbonaceous asteroids.
It had been titled the lowest numbered asteroid with no previously known period until its opposition in 2014, when a photometric light-curve analysis was performed at the Uruguayan Los Algarrobos Observatory (OLASU, I38). It rendered a rotation period of 7001112080000000000♠11.208±0.001 hours with a brightness amplitude of 6999130000000000000♠0.13±0.02 in magnitude. Still in 2014, Eduardo Alvarez at OLASU went on to determine the period of the next lowest numbered asteroid with no previously known period, 457 Alleghenia. Since then all asteroids numbered up to 500 had their rotation period determined. As of 2014, there are still 22 asteroids with no known period up to number 1000.
The minor planet was named from Greek mythology for Admete, daughter of king Eurystheus, who appointed the Twelve Labors of Heracles, after whom the minor planet 5143 Heracles is named. One of the labors was to obtaining the golden girdle of Hippolyta, because Admete coveted it.