|
Discovery
|
|
|---|---|
| Discovered by | J. Chacornac |
| Discovery date | October 28, 1854 |
|
Designations
|
|
| Named after | Polyhymnia |
| Alternate name(s) | A887 HA; 1938 FE; 1953 AK; 1957 YL; 1963 DG; 1976 YT7 |
| Minor planet category |
Main belt |
| Epoch December 31, 2006 (JD 2454100.5) | |
| Aphelion | 573.325 Gm (3.832 AU) |
| Perihelion | 283.846 Gm (1.897 AU) |
| Semi-major axis | 428.585 Gm (2.865 AU) |
| Eccentricity | 0.338 |
| Orbital period | 1771.195 d (4.85 a) |
| Average orbital speed | 17.08 km/s |
| Mean anomaly | 148.947° |
| Inclination | 1.871° |
| Longitude of ascending node | 8.590° |
| Argument of perihelion | 338.240° |
|
Physical characteristics
|
|
| Dimensions | 50-120 km [1] |
| Mass | 1.3-18.0×1017 kg |
| Mean density | 2.0? g/cm³ |
| Equatorial surface gravity | 0.014-0.033 m/s² |
| Escape velocity | 0.026-0.063 km/s |
| Rotation period | 0.77504 d (18.601 h) [2] |
| Albedo | 0.10? |
| Temperature | ~164 K |
| Spectral type | S |
| Absolute magnitude (H) | 8.55 |
33 Polyhymnia ( /pɒliˈhɪmniə/ pol-ee-him-nee-ə) is a main belt asteroid.
It was discovered by J. Chacornac on October 28, 1854 and named after Polyhymnia, the Greek Muse of sacred hymns.
Due to its high eccentricity (0.338), one of the highest for a lower numbered minor planet, on rare close approaches it can reach tenth magnitude, as on September 9 2014 when it will be at magnitude 9.8, being 0.894 A.U. from Earth.
|
|
|||||
|
||||||||||||||||||||||