177 Irma is a fairly large and dark
main belt
The asteroid belt is a torus-shaped region in the Solar System, centered on the Sun and roughly spanning the space between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies called asteroids ...
asteroid
An asteroid is a minor planet—an object larger than a meteoroid that is neither a planet nor an identified comet—that orbits within the Solar System#Inner Solar System, inner Solar System or is co-orbital with Jupiter (Trojan asteroids). As ...
. It was discovered by the French brothers
Paul Henry and Prosper Henry
Paul-Pierre Henry (21 August 1848 – 4 January 1905) and his brother Prosper-Mathieu Henry (10 December 1849 – 25 July 1903) were French opticians and astronomers.
They made refracting telescopes and instruments for observatories, and were ...
on November 5, 1877. Paul was credited for this discovery. The meaning of the name Irma is unknown.
observations of this asteroid at the Organ Mesa Observatory in
Las Cruces, New Mexico
Las Cruces (; ; lit. 'the crosses') is the List of municipalities in New Mexico, second-most populous city in the U.S. state of New Mexico and the county seat, seat of Doña Ana County, New Mexico, Doña Ana County. As of the 2020 United States ce ...
in 2011 gave a
light curve
In astronomy, a light curve is a graph (discrete mathematics), graph of the Radiance, light intensity of a celestial object or region as a function of time, typically with the magnitude (astronomy), magnitude of light received on the ''y''-axis ...
with a period of 13.856 ± 0.001 hours and a brightness variation of 0.30 ± 0.03 in
magnitude
Magnitude may refer to:
Mathematics
*Euclidean vector, a quantity defined by both its magnitude and its direction
*Magnitude (mathematics), the relative size of an object
*Norm (mathematics), a term for the size or length of a vector
*Order of ...
.
References
External links
*
*
Background asteroids
Irma
Irma
C-type asteroids (Tholen)
Ch-type asteroids (SMASS)
18771105
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