Discovery | |
---|---|
Discovered by | C. H. F. Peters, 1878 |
Discovery date | 22 September 1878 |
Designations | |
(190) Ismene | |
Pronunciation | /ɪsˈmiːniː/ [1] |
Named after | Ismene |
A878 SA; 1947 QJ; 1951 DB | |
Main belt ( Hilda) | |
Orbital characteristics [2] | |
Epoch 31 July 2016 ( JD 2457600.5) | |
Uncertainty parameter 0 | |
Observation arc | 121.44 yr (44357 d) |
Aphelion | 4.6480 AU (695.33 Gm) |
Perihelion | 3.3248 AU (497.38 Gm) |
3.9864 AU (596.36 Gm) | |
Eccentricity | 0.16597 |
7.96 yr (2907.2 d) | |
134.92 ° | |
0° 7m 25.788s / day | |
Inclination | 6.1772° |
175.48° | |
271.47° | |
Physical characteristics | |
79.5 km
[2] 90 km [3] | |
6.52 h (0.272 d) 3 | |
0.066 | |
P | |
7.77
[4] 7.59 [2] | |
190 Ismene is a very large main belt asteroid. It was discovered by German-American astronomer C. H. F. Peters on September 22, 1878, in Clinton, New York, and named after Ismene, the sister of Antigone in Greek mythology.
Being a P-type asteroid, it has a very dark surface. Ismene orbits near the outer edge of the asteroid belt. It is one of the largest members of the Hilda asteroid family, which are locked in 3:2 resonance with the planet Jupiter. [5]