Doris (minor planet designation: 48 Doris) is one of the largest main belt asteroids. It was discovered on 19 September 1857 by Hermann Goldschmidt from his balcony in Paris.
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Discovery | |
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Discovered by | Hermann Mayer Salomon Goldschmidt |
Discovery date | 19 September 1857 |
Designations | |
MPC designation | (48) Doris |
Pronunciation | /ˈdɔːrɪs/[1] |
Named after | Doris |
Minor planet category | Main belt |
Adjectives | Dorian /ˈdɔːriən/[2] |
Orbital characteristics[3] | |
Epoch 31 December 2006 (JD 2454100.5) | |
Aphelion | 500.093 Gm (3.343 AU) |
Perihelion | 430.463 Gm (2.877 AU) |
Semi-major axis | 465.278 Gm (3.110 AU) |
Eccentricity | 0.075 |
Orbital period (sidereal) | 2003.453 d (5.49 a) |
Mean anomaly | 336.191° |
Inclination | 6.554° |
Longitude of ascending node | 183.754° |
Argument of perihelion | 257.583° |
Physical characteristics | |
Dimensions | c/a = 0.72±0.01[4] 278 km × 142 km[5] |
Mean diameter | 215±3 km[4] 221.8±7.5 km (IRAS)[3] |
Mass | (6.9±2.9)×1018 kg[4] (12.3±6.0)×1018 kg[lower-alpha 1][6] |
Mean density | 1.32±0.55 g/cm3[4] 2.12±1.07 g/cm3[7] |
Synodic rotation period | 11.89 h[3] |
Geometric albedo | 0.066[4] 0.062[8] |
Spectral type | C[3] |
Absolute magnitude (H) | 6.90[3] |
To find a name for the object, Jacques Babinet of the Academy of Sciences created a shortlist and asked the geologist Élie de Beaumont to make the selection. De Beaumont chose Doris, after an Oceanid in Greek mythology. Since Doris was discovered on the same night as 49 Pales, de Deaumont suggested naming the two "The Twins".[9]
An occultation on 19 March 1981 suggested a diameter of 219±25 km.[10] Observations of an occultation on 14 October 1999, using four well-placed chords, indicate an ellipsoid of 278×142 km and that 48 Doris is an extremely irregularly shaped object.[5]
Doris will pass within 0.019 AU of Pallas in June 2132.[11]
48 Doris is a location in the text-based science fiction game Federation 2.[citation needed]
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Large asteroids (over 200 km in diameter) | |
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Asteroids over 900 km | Ceres (a dwarf planet) |
Asteroids between 500 and 600 km | |
Asteroids between 300 and 500 km | |
Asteroids between 200 and 300 km |
Small Solar System bodies | |||||||
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Minor planets |
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Comets |
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Other |
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