Monday, May 9, 2011

Moonday: Dactyl

Dactyl is that itty-bitty dot to the right, the first known satellite orbiting an asteroid, 243 Ida, which is the larger body to the left. According to Wikipedia,
Ida's moon, Dactyl, was discovered by mission member Ann Harch in images returned from Galileo. It was named after the Dactyls, creatures which inhabited Mount Ida in Greek mythology. Dactyl, being only 1.4 kilometres (4,600 ft) in diameter, is about one-twentieth the size of Ida. Its orbit around Ida could not be determined with much accuracy. However, the constraints of possible orbits allowed a rough determination of Ida's density, which revealed that it is depleted of metallic minerals. Dactyl and Ida share many characteristics, suggesting a common origin.

No comments: