177 Irma
Discovery | |
---|---|
Discovered by | P. P. Henry, 1877 |
Discovery date | 5 November 1877 |
Designations | |
MPC designation | (177) Irma |
Minor planet category | Main belt |
Orbital characteristics[1] | |
Epoch 31 July 2016 (JD 2457600.5) | |
Uncertainty parameter 0 | |
Observation arc | 115.30 yr (42113 d) |
Aphelion | 3.4260 AU (512.52 Gm) |
Perihelion | 2.1110 AU (315.80 Gm) |
2.7685 AU (414.16 Gm) | |
Eccentricity | 0.23749 |
4.61 yr (1682.5 d) | |
42.096° | |
0° 12m 50.256s / day | |
Inclination | 1.3893° |
347.55° | |
38.184° | |
Earth MOID | 1.11401 AU (166.654 Gm) |
Jupiter MOID | 2.03001 AU (303.685 Gm) |
TJupiter | 3.296 |
Physical characteristics | |
Mean radius | 36.61±0.8 km |
Synodic rotation period | 13.856 h (0.5773 d)[1][2] |
0.0527±0.002 | |
C | |
Absolute magnitude (H) | 9.49 |
Irma (minor planet designation: 177 Irma) is a fairly large and dark main belt asteroid. It was discovered by the French brothers Paul Henry and Prosper Henry on November 5, 1877. Paul was credited for this discovery. The meaning of the name Irma is unknown.[3]
Photometric observations of this asteroid at the Organ Mesa Observatory in Las Cruces, New Mexico in 2011 gave a light curve with a period of 13.856 ± 0.001 hours and a brightness variation of 0.30 ± 0.03 in magnitude.[2]
References[]
- ^ a b Yeomans, Donald K., "177 Irma", JPL Small-Body Database Browser, NASA Jet Propulsion Laboratory, retrieved 6 May 2016.
- ^ a b Pilcher, Frederick (April 2012), "Rotation Period Determinations for 31 Euphrosyne, 65 Cybele, 154 Bertha 177 Irma, 200 Dynamene, 724 Hapag, 880 Herba, and 1470 Carla", The Minor Planet Bulletin, vol. 39, no. 2, pp. 57–60, Bibcode:2012MPBu...39...57P.
- ^ Schmadel, Lutz D. (2012), Dictionary of Minor Planet Names (6th ed.), Springer, p. 29, ISBN 3642297188.
External links[]
- 177 Irma at AstDyS-2, Asteroids—Dynamic Site
- 177 Irma at the JPL Small-Body Database
Categories:
- Minor planet object articles (numbered)
- Background asteroids
- Discoveries by Paul Henry and Prosper Henry
- Minor planets with names of unknown origin
- Named minor planets
- C-type asteroids (Tholen)
- Ch-type asteroids (SMASS)
- Astronomical objects discovered in 1877
- Main-belt-asteroid stubs