.png) A three-dimensional model of 147 Protogeneia based on itslight curve | |
| Discovery[1] | |
|---|---|
| Discovered by | Lipót Schulhof |
| Discovery date | 10 July 1875 |
| Designations | |
| (147) Protogeneia | |
| Pronunciation | /ˌprɒtoʊdʒɪˈniːə/[1] |
Named after | Protogeneia |
| A875 PA | |
| Main belt | |
| Orbital characteristics[2][3] | |
| Epoch 31 July 2016 (JD 2457600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 132.02 yr (48222 d) |
| Aphelion | 3.2230 AU (482.15 Gm) |
| Perihelion | 3.04727 AU (455.865 Gm) |
| 3.13512 AU (469.007 Gm) | |
| Eccentricity | 0.028020 |
| 5.55yr (2027.6d) | |
Averageorbital speed | 16.82 km/s |
| 92.9051° | |
| 0° 10m 39.184s / day | |
| Inclination | 1.9309° |
| 248.357° | |
| 100.692° | |
| Earth MOID | 2.03996 AU (305.174 Gm) |
| Jupiter MOID | 1.90385 AU (284.812 Gm) |
| TJupiter | 3.211 |
| Physical characteristics | |
| 66.465±2.55km[3] 59.22 ± 5.225 km[4] | |
| Mass | (1.23 ± 0.05) × 1019 kg[4] |
Meandensity | 14.13 ± 3.78 g/cm3[4] |
Equatorialsurface gravity | 0.0371 m/s² |
Equatorialescape velocity | 0.0703 km/s |
| 7.8528 h (0.32720 d)[3][5] | |
| 0.0492±0.004[3] | |
| Temperature | ~157K |
| C | |
| 12.4 to 14.5 | |
| 8.27[5] 8.8[3] | |
147 Protogenia is a largemain beltasteroid that was discovered by Hungarian astronomerLipót Schulhof on July 10, 1875, from theVienna Observatory; it was his only asteroid discovery. Its name is Greek for "first born" and was chosen byKarl L. Littrow in allusion to the fact that this was the first asteroid discovered by an astronomer who was already known for work in other fields of astronomy.[6]
This object has a loworbital eccentricity andinclination. With an orbital period roughly double that of the planetJupiter, it has been identified as a member of the Hecuba group of asteroids that share a 2:1 mean-motionorbital resonance with the giant planet.[7] Based upon its spectrum, it has aTholen classification as aC-type asteroid,[8] which indicates that it has a dark surface and probably a primitive composition ofcarbonaceous material.
Photometric observations of this asteroid at the Altimira Observatory in 2004 gave alight curve with a period of 7.8528 ± 0.0008 hours and a brightness variation of 0.28 inmagnitude.[5] A photometric study was reported in 2006 from theYunnan Observatory in China, finding a matching period of 7.852 hours and a brightness variation of 0.25 magnitude. They estimate the ratio of the lengths for the asteroid's major and minor axes is at least 1.26:1.[9]
There is one reportedstellaroccultation by Protogeneia, on May 28, 2002, fromTexas.[citation needed]
