Minerva (minor planet designation: 93 Minerva) is a large trinary main-belt asteroid. It is a C-type asteroid, meaning that it has a dark surface and possibly a primitive carbonaceous composition. It was discovered by J. C. Watson on 24 August 1867, and named after Minerva, the Roman equivalent of Athena, goddess of wisdom. An occultation of a star by Minerva was observed in France, Spain and the United States on 22 November 1982. An occultation diameter of ~170 km was measured from the observations. Since then two more occultations have been observed, which give an estimated mean diameter of ~150 km.[5][6]
A three-dimensional model of 93 Minerva based on its light curve.
| |
| Discovery | |
|---|---|
| Discovered by | James Craig Watson |
| Discovery site | Ann Arbor, Michigan |
| Discovery date | 24 August 1867 |
| Designations | |
| (93) Minerva | |
| Pronunciation | /mɪˈnɜːrvə/[1] |
Named after | Minerva |
| 1949 QN2, A902 DA | |
| Main belt | |
| Adjectives | Minervian, Minervean /mɪˈnɜːrviən/ |
| Orbital characteristics[2] | |
| Epoch 31 July 2016 (JD 2457600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 146.14 yr (53379 d) |
| Aphelion | 3.1429 AU (470.17 Gm) |
| Perihelion | 2.3711 AU (354.71 Gm) |
| 2.7570 AU (412.44 Gm) | |
| Eccentricity | 0.13998 |
| 4.58 yr (1672.0 d) | |
Average orbital speed | ~17.86 km/s |
| 262.022° | |
| 0° 12m 55.116s / day | |
| Inclination | 8.56143° |
| 4.06265° | |
| 274.543° | |
| Physical characteristics | |
| 154.155±1.298 km (IRAS)[2] 156 km[3] | |
| Mass | 3.8×1018 kg (calculated)[a] |
Mean density | 1.9 g/cm3[3] |
Equatorial surface gravity | 4.139 cm/s2 (0.004221 g)[4] |
Equatorial escape velocity | 8.035 cm/s[4] |
| 5.982 h (0.2493 d)[2] | |
| 0.056±0.008[2] | |
| C[2] G?[3] | |
| 7.91[2] | |
On 16 August 2009, at 13:36 UT, the Keck Observatory's adaptive optics system revealed that the asteroid 93 Minerva possesses 2 small moons.[7] They are 4 and 3 km in diameter and the projected separations from Minerva correspond to 630 km (8.8 x Rprimary) and 380 km (5.2 x Rprimary) respectively.[7] They have been named Aegis[8] (/ˈiːdʒɪs/)[9] and Gorgoneion[8] (/ˌɡɔːrɡəˈnaɪən/).[10]
