Discovered by P. P. Henry, 1877 Minor planet category Main belt Aphelion 3.4260 AU (512.52 Gm) Discovered 5 November 1877 Discoverer Paul Henry Asteroid group Asteroid belt | Discovery date 5 November 1877 Observation arc 115.30 yr (42113 d) Perihelion 2.1110 AU (315.80 Gm) Orbits Sun Discovery site Paris Observatory | |
Similar 188 Menippe, 162 Laurentia, 127 Johanna | ||
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.
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.
References
177 Irma Wikipedia(Text) CC BY-SA