817 Annika
| Discovery | |
|---|---|
| Discovered by | Max Wolf |
| Discovery date | February 6, 1916 |
| Designations | |
| 1916 YW | |
| Main belt (Eunomia family) | |
| Orbital characteristics | |
| Epoch 8 August 2005 (JD 2453600.5) | |
| Aphelion | 456.6 Gm (3.053 AU) |
| Perihelion | 317.9 Gm (2.125 AU) |
| 387.3 Gm (2.589 AU) | |
| Eccentricity | 0.179 |
| 1521.586 d (4.20 a) | |
Average orbital speed | 18.36 km/s |
| 224.421° | |
| Inclination | 11.345° |
| 125.701° | |
| 284.937° | |
| Physical characteristics | |
| Dimensions | 22 km |
| Mass | ~1.5×1016 kg (estimate) |
Mean density | ~2.7 g/cm³ (estimate)[3] |
| ~0.008 m/s² (estimate) | |
| ~0.013 km/s (estimate) | |
| 0.440 d | |
| Albedo | 0.174 |
| Temperature |
~169 K max: 264K (-9° C) |
Spectral type | S-type asteroid |
| 10.80 | |
|
| |
817 Annika is a mid-sized Eunomian asteroid.
References
- PDS lightcurve data
- G. A. Krasinsky et al. Hidden Mass in the Asteroid Belt, Icarus, Vol. 158, p. 98 (2002).
External links
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