Discovery
Thirty inner satellites are currently known, found orbiting around all four of the giant planets (Jupiter, Saturn, Uranus and Neptune). Because of their small size, and glare from the nearby planet, they can be very difficult to observe from Earth. Some, such as Pan and Daphnis at Saturn, and Naiad at Neptune, have only ever been observed by spacecraft.
The first inner satellite to be observed was Amalthea, discovered by E. E. Barnard in 1892. Next were the Saturnian moons Epimetheus and Janus, observed in 1966. These two moons are co-orbital (that is, they share the same orbit), and the resulting confusion over their status was not resolved until the Voyager 1 flyby in 1980. Most of the remaining inner satellites were discovered by spacecraft Voyager 1 and Voyager 2 during their flybys of Jupiter (1979), Saturn (1980), Uranus (1986) and Neptune (1989).
The most recent discoveries have been two moons of Uranus (Mab and Cupid), found using the Hubble Space Telescope in 2003, and Daphnis found orbiting Saturn by the Cassini spacecraft in 2005.
Read more about this topic: Inner Moon
Famous quotes containing the word discovery:
“We are all humiliated by the sudden discovery of a fact which has existed very comfortably and perhaps been staring at us in private while we have been making up our world entirely without it.”
—George Eliot [Mary Ann (or Marian)
“That the discovery of this great truth, which lies so near and obvious to the mind, should be attained to by the reason of so very few, is a sad instance of the stupidity and inattention of men, who, though they are surrounded with such clear manifestations of the Deity, are yet so little affected by them, that they seem as it were blinded with excess of light.”
—George Berkeley (1685–1753)
“As the mother of a son, I do not accept that alienation from me is necessary for his discovery of himself. As a woman, I will not cooperate in demeaning womanly things so that he can be proud to be a man. I like to think the women in my son’s future are counting on me.”
—Letty Cottin Pogrebin (20th century)