177 Irma

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177 Irma
Discovery
Discovered by P. P. Henry, 1877
Discovery date November 5, 1877
Designations
Minor planet category Main belt
Orbital characteristics[1]
Aphelion 3.426 AU
Perihelion 2.115 AU
2.770 AU
Eccentricity 0.237
4.61 years
Inclination 1.39°
Physical characteristics
13.856[2] hours
Albedo 0.053
Spectral type
C
9.49

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[edit]

  1. ^ Yeomans, Donald K., 177 Irma, JPL Small-Body Database Browser (NASA Jet Propulsion Laboratory), retrieved 2013-03-30. 
  2. ^ 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, Bulletin of the Minor Planets Section of the Association of Lunar and Planetary Observers 39 (2): 57–60, Bibcode:2012MPBu...39...57P. 
  3. ^ Schmadel, Lutz D. (2012), Dictionary of Minor Planet Names (6th ed.), Springer, p. 29, ISBN 3642297188.