61 Danaë
From Wikipedia, the free encyclopedia
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Discovery
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| Discovered by | H. Goldschmidt |
| Discovery date | September 9, 1860 |
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Designations
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| Alternative names | A917 SM; 1953 RL1 |
| Minor planet category |
Main belt |
| Epoch June 14, 2006 (JD 2453900.5) | |
| Aphelion | 520.969 Gm (3.482 AU) |
| Perihelion | 371.280 Gm (2.482 AU) |
| Semi-major axis | 446.125 Gm (2.982 AU) |
| Eccentricity | 0.168 |
| Orbital period | 1881.025 d (5.15 a) |
| Average orbital speed | 17.13 km/s |
| Mean anomaly | 91.103° |
| Inclination | 18.218° |
| Longitude of ascending node | 333.774° |
| Argument of perihelion | 13.831° |
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Physical characteristics
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| Dimensions | 82.0 km |
| Mass | 3.2×1017 kg |
| Mean density | 1.1 g/cm³ |
| Equatorial surface gravity | 0.0126 m/s² |
| Escape velocity | 0.0322 km/s |
| Rotation period | 0.4771 d (11.45 h) [1] |
| Albedo | 0.2224±0.025 [2] |
| Temperature | ~155 K |
| Spectral type | S |
| Absolute magnitude | 7.68 |
61 Danaë (pronounced /ˈdænəji/ dan'-ə-yee, sometimes /dəˈneɪə/ də-nay'-ə) is a quite large, rocky Main belt asteroid. It was discovered by H. Goldschmidt on September 9, 1860 and named after Danaë, the mother of Perseus in Greek mythology.
A satellite has been suggested in 1985 based on lightcurve data. [3] The primary's ellipsoid is then 85×80×75 km, and 101 km away would be the moon, measuring 55×30×30 km. The density of both would be 1.1 g/cm³.
[edit] Trivia
- It is the lowest-numbered asteroid with diacritical characters in its official name.
[edit] References
- A. Cellino, R. Pannunzio, V. Zappalà, P. Farinella, and P. Paolicchi, 1985, Do we observe light curves of binary asteroids?, Astronomy and Astrophysics, Vol. 144, No. 2, pp. 355–362.
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