title: Galileo encounter with 951 gaspra: first pictures of an asteroid.
abstract: Galileo images of Gaspra reveal it to be an irregularly shaped object (19 by 12 by 11 kilometers) that appears to have been created by a catastrophic collisional disruption of a precursor parent body. The cratering age of the surface is about 200 million years. Subtle albedo and color variations appear to correlate with morphological features: Brighter materials are associated with craters especially along the crests of ridges, have a stronger 1-micrometer absorption, and may represent freshly excavated mafic materials; darker materials exhibiting a significantly weaker 1-micrometer absorption appear concentrated in interridge areas. One explanation of these patterns is that Gaspra is covered with a thin regolith and that some of this material has migrated downslope in some areas.
authors.forename: M J
authors.initials: MJ
authors.lastname: Belton
authors.forename: J
authors.initials: J
authors.lastname: Veverka
authors.forename: P
authors.initials: P
authors.lastname: Thomas
authors.forename: P
authors.initials: P
authors.lastname: Helfenstein
authors.forename: D
authors.initials: D
authors.lastname: Simonelli
authors.forename: C
authors.initials: C
authors.lastname: Chapman
authors.forename: M E
authors.initials: ME
authors.lastname: Davies
authors.forename: R
authors.initials: R
authors.lastname: Greeley
authors.forename: R
authors.initials: R
authors.lastname: Greenberg
authors.forename: J
authors.initials: J
authors.lastname: Head
authors.forename: S
authors.initials: S
authors.lastname: Murchie
authors.forename: K
authors.initials: K
authors.lastname: Klaasen
authors.forename: T V
authors.initials: TV
authors.lastname: Johnson
authors.forename: A
authors.initials: A
authors.lastname: McEwen
authors.forename: D
authors.initials: D
authors.lastname: Morrison
authors.forename: G
authors.initials: G
authors.lastname: Neukum
authors.forename: F
authors.initials: F
authors.lastname: Fanale
authors.forename: C
authors.initials: C
authors.lastname: Anger
authors.forename: M
authors.initials: M
authors.lastname: Carr
authors.forename: C
authors.initials: C
authors.lastname: Pilcher