Dactyl

243 Ida has a moon named Dactyl, official designation (243) Ida I. It was discovered in images taken by the Galileo spacecraft during its flyby in 1993. These images provided the first direct confirmation of an asteroid moon. At the time, it was separated from Ida by a distance of 90 kilometres (56 mi), moving in a prograde orbit. Dactyl is heavily cratered, like Ida, and consists of similar materials. Its origin is uncertain, but evidence from the flyby suggests that it originated as a fragment of the Koronis parent body 
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== Discovery ==
Dactyl was found on 17 February 1994 by Galileo mission member Ann Harch, while examining delayed image downloads from the spacecraft. Galileo recorded 47 images of Dactyl over an observation period of 5.5 hours in August 1993. The spacecraft was 10,760 kilometres (6,690 mi) from Ida and 10,870 kilometres (6,750 mi) from Dactyl when the first image of the moon was captured, 14 minutes before Galileo made its closest approach.
Category:Moons
Category:Asteroids
Category:Minor Planet Moon
Category:Objects Not in Hydrostatic Equilibrium
Category:Objects with No Atmosphere
Category:Inner Solar System Object
Category:Main Belt
Category:Prograde Satellite
Category:Named Objects
Category:Named Minor Planet Moons