185 Eunike
Discovery | |
---|---|
Discovered by | C. H. F. Peters, 1878 |
Discovery date | 1 March 1878 |
Designations | |
MPC designation | (185) Eunike |
Pronunciation | /juːˈnaɪkiː/[1] |
Named after | Εὐνίκη Eynīkē |
Minor planet category | Main belt |
Adjectives | Eunikean /juːnɪˈkiːən/ |
Orbital characteristics[2] | |
Epoch 31 July 2016 (JD 2457600.5) | |
Uncertainty parameter 0 | |
Observation arc | 131.77 yr (48128 d) |
Aphelion | 3.0924 AU (462.62 Gm) |
Perihelion | 2.3843 AU (356.69 Gm) |
2.7383 AU (409.64 Gm) | |
Eccentricity | 0.12930 |
4.53 yr (1655.1 d) | |
327.48° | |
0° 13m 3.036s / day | |
Inclination | 23.238° |
153.84° | |
224.01° | |
Earth MOID | 1.41759 AU (212.068 Gm) |
Jupiter MOID | 2.40697 AU (360.078 Gm) |
TJupiter | 3.222 |
Physical characteristics | |
Dimensions | 157.51±2.6 km[2] 160.61 ± 5.00 km[3] |
Mass | (3.56 ± 2.61) × 1018 kg[3] |
Mean density | 1.64 ± 1.21 g/cm3[3] |
Synodic rotation period | 21.797 h (0.9082 d)[2] 21.812 ± 0.001 hours[4] |
0.0638±0.002 | |
C | |
Absolute magnitude (H) | 7.62,[2] 7.45 ± 0.01[4] |
Eunike (minor planet designation: 185 Eunike) is a dark and very large main-belt asteroid, with an approximate diameter of 157 kilometres. It has a primitive carbonaceous composition.
It was discovered by C. H. F. Peters on March 1, 1878, in Clinton, New York and named after Eunike, a Nereid in Greek mythology whose name means 'happy victory'. The name was chosen to celebrate the Treaty of San Stefano (1878).
Based upon photometric observations made between 2010 and 2014, this asteroid has a rotation period of 21.812 ± 0.001 hours and a brightness variation of 0.08 ± 0.01 in magnitude. At opposition, the absolute magnitude was measured at 7.45 ± 0.01. It displays a hemispheric albedo dichotomy similar to that on 4 Vesta.[4]
As of 17 September 2020, there have been thirteen observed occultations of stars by Eunike.
References[]
- ^ Noah Webster (1884) A Practical Dictionary of the English Language
- ^ a b c d "185 Eunike". JPL Small-Body Database. NASA/Jet Propulsion Laboratory. Retrieved 12 May 2016.
- ^ a b c Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science, vol. 73, pp. 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009. See Table 1.
- ^ a b c Pilcher, Frederick; et al. (October 2014), "A Comprehensive Photometric Investigation of 185 Eunike", of the Minor Planets Section of the Association of Lunar and Planetary Observers, 41 (4): 244–250, Bibcode:2014MPBu...41..244P.
External links[]
- 185 Eunike at AstDyS-2, Asteroids—Dynamic Site
- 185 Eunike at the JPL Small-Body Database
- Minor planet object articles (numbered)
- Background asteroids
- Discoveries by Christian Peters
- Minor planets named from Greek mythology
- Named minor planets
- Objects observed by stellar occultation
- C-type asteroids (Tholen)
- C-type asteroids (SMASS)
- Astronomical objects discovered in 1878
- C-type main-belt-asteroid stubs