Astronomy:91 Aegina
 Orbital diagram | |
| Discovery | |
|---|---|
| Discovered by | Édouard Stephan |
| Discovery date | 4 November 1866 |
| Designations | |
| (91) Aegina | |
| Pronunciation | /ɪˈdʒaɪnə/[1] |
| Named after | Aegina |
| Minor planet category | Main belt |
| Adjectives | Aeginetan /iːdʒɪˈniːtən/[2] |
| Orbital characteristics | |
| Epoch 31 December 2006 (JD 2454100.5) | |
| |{{{apsis}}}|helion}} | 428.453 Gm (2.864 astronomical unit|AU) |
| |{{{apsis}}}|helion}} | 346.826 Gm (2.318 AU) |
| 387.640 Gm (2.591 AU) | |
| Eccentricity | 0.105 |
| Orbital period | 1,523.536 d (4.171 yr) |
| Average Orbital speed | 18.45 km/s |
| Mean anomaly | 183.458° |
| Inclination | 2.109° |
| Longitude of ascending node | 10.806° |
| 73.371° | |
| Physical characteristics | |
| Dimensions | 109.8 km |
| Mass | 1.4×1018 kg |
Equatorial surface gravity | 0.0307 m/s² |
Equatorial escape velocity | 0.0580 km/s |
| Rotation period | 6.03 hours |
| Geometric albedo | 0.043 [3] |
| C | |
| Absolute magnitude (H) | 8.84 |
Aegina (from Latin Aegīna, Aegīnēta),[4] minor planet designation 91 Aegina, is a large main-belt asteroid. It was discovered by a France astronomer Édouard Jean-Marie Stephan on 4 November 1866. It was his second and final asteroid discovery. The first was 89 Julia. The asteroid's name comes from Aegina, a Greek mythological figure associated with the island of the same name.
This body is orbiting the Sun with a period of 4.17 years and an eccentricity of 0.105. The orbit of this object brings it to within 4.9 Gm of the dwarf planet Ceres, and the resulting gravitational interaction has been used to produce mass estimates of the latter.[5] The cross-section size of the asteroid is 110 km and it has a rotation period of six hours. The surface coloring of 91 Aegina is very dark and this C-type asteroid has probably a primitive carbonaceous composition. Observation of absorption bands at wavelengths of 0.7 and 3μm indicate the presence of hydrated minerals and/or ice grains on the surface.[6]
References
- ↑ Noah Webster (1884) A Practical Dictionary of the English Language
- ↑ Figueira (1981) Aegina, society and politics
- ↑ Asteroid Data Sets
- ↑ Charlton T. Lewis, Charles Short, A Latin Dictionary
- ↑ Viateau, B.; Rapaport, M. (June 1998). "The mass of (1) Ceres from its gravitational perturbations on the orbits of 9 asteroids". Astronomy and Astrophysics 334: 729–735. Bibcode: 1998A&A...334..729V.
- ↑ "Hydrated silicates on main-belt asteroids: Correlation of the 0.7- and 3 micron absorption bands". EPSC-DPS Joint Meeting 2011, held 2–7 October 2011 in Nantes, France. October 2011. p. 637. Bibcode: 2011epsc.conf..637H. https://meetingorganizer.copernicus.org/EPSC-DPS2011/EPSC-DPS2011-637-1.pdf. Retrieved 2020-11-22.
External links
- Lightcurve plot of 91 Aegina, Palmer Divide Observatory, B. D. Warner (2009)
- Asteroid Lightcurve Database (LCDB), query form (info )
- Dictionary of Minor Planet Names, Google books
- Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
- Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
- 91 Aegina at AstDyS-2, Asteroids—Dynamic Site
- 91 Aegina at the JPL Small-Body Database
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