878 Mildred
| Discovery [1][2] | |
|---|---|
| Discovered by |
S. B. Nicholson H. Shapley |
| Discovery site | Mount Wilson |
| Discovery date | 6 September 1916 |
| Designations | |
| MPC designation | 878 |
| 1916 f, 1985 VG6, 1991 GZ8 | |
|
Nysa family [3] Main belt  | |
| Orbital characteristics [1] | |
| Epoch 31 July 2016 (JD 2457600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 99.57 yr (36368 days) |
| Aphelion | 2.8953 AU (433.13 Gm) |
| Perihelion | 1.8286 AU (273.55 Gm) |
| 2.3619 AU (353.34 Gm) | |
| Eccentricity | 0.22580 |
| 3.63 yr (1325.9 d) | |
| 198.89° | |
| 0° 16m 17.472s / day | |
| Inclination | 2.0648° |
| 172.83° | |
| 190.14° | |
| Earth MOID | 0.825074 AU (123.4293 Gm) |
| Jupiter MOID | 2.55379 AU (382.042 Gm) |
| Jupiter Tisserand parameter | 3.515 |
| Physical characteristics | |
| Dimensions | ~4 km[4] |
| 2.660 h (0.1108 d)[1] | |
| S[3] | |
| 14.7[1] | |
|
| |
878 Mildred is a minor planet in the main belt orbiting the Sun. It is the lowest numbered, and thus the namesake, of the Mildred family of asteroids, a subgroup of the Nysa family.[3] The Mildred subgroup, and by extension 878 Mildred itself, is thought to have been formed by a recent fragmentation event from a larger asteroid.[3]
Discovery
878 Mildred was originally discovered in 1916 using the 1.5 m Hale Telescope at the Mount Wilson Observatory, but was subsequently lost until it was again observed on single nights in 1985 and 1991 (a lost asteroid).[2] Initially only two observations of the asteroid were taken on 1916-09-06 which does not allow for an accurate orbital determination, however interest in the object prompted further investigation and more measurements were taken in late September and October.[4] The asteroid was re-discovered in 1991 by Gareth V. Williams.[5]
Physical properties
By comparing the asteroid's perceived brightness and the then computed distance from the Sun they arrived at an absolute visual magnitude of 14.3, which if one assumes Mars-like albedo gives an approximate diameter of 3 to 5 kilometers.[4]
References
- 1 2 3 4 "JPL Small-Body Database Browser: 878 Mildred (1916 f)" (2015-04-10 last obs). Retrieved 3 May 2016.
- 1 2 "IAU Circular: IAUC 5275". 1991-05-25.
- 1 2 3 4 Cellino, A.; et al. (August 2001). "The Puzzling Case of the Nysa–Polana Family". Icarus. 152 (2): 225–237. Bibcode:2001Icar..152..225C. doi:10.1006/icar.2001.6634.
- 1 2 3 Shapley, H.; Nicholson, S. B. (1917). "The Orbit and Probable Size of a Very Faint Asteroid (878) Mildred". Astronomical Journal. 30 (710): 127–128. Bibcode:1917AJ.....30..127S. doi:10.1086/104199.
- ↑ "MPC staff - Gareth Williams". Minor Planet Center. International Astronomical Union. Retrieved 26 August 2014.
