45 Eugenia
45 Eugenia (
ew-jee'-nee-a) is a large
Main belt asteroid. It is famed as one of the first asteroids to be found to have a
moon orbiting it.
Eugenia was discovered in 1857 by
Hermann Goldschmidt. It was named after
Empress Eugenia di Montijo, the wife of
Napoleon III, and was the first asteroid to be named after a real person, rather than a figure from classical legend (although there had been controversy about whether
12 Victoria was really named for the mythological figure or for
Queen Victoria).
Eugenia is a large asteroid, with a
diameter of 214 km. It is an
F-type asteroid, which means that it is very dark in colouring (darker than
soot) with a
carbonaceous composition. Like
Mathilde, its density appears to be unusually low, indicating that it may be a loosely-packed rubble pile, not a monolithic object.
In 1998, astronomers at the
Canada-France-Hawaii Telescope on
Mauna Kea,
Hawaii, discovered a small
moon orbiting Eugenia. This was the first time an
asteroidal moon had been discovered by a ground-based telescope. Eugenia's moon has been named
(45) Eugenia I Petit-Prince, after Empress Eugenia's son, the
Prince Imperial. The moon is much smaller than Eugenia, about 13 km in
diameter, and takes five days to complete an orbit around it.
Dactyl and
Ida - Another
asteroid and
asteroid moon system catalogued by astronomers
*
Johnston Archive data*
10/14/1999 Astronomical Picture of Day*
SwRI Press Release*
Orbit of Petit-Prince, companion of Eugenia*
IAUC 8177
