Aster › Space program › 243 Ida
243 Ida
Position on the route: 22/130 · level needed 62 · journey (Mk0 engine) 10.4 h
By the numbers
| Length | ≈ 60 km |
|---|---|
| Year | 4.84 years |
| Moon | Dactyl |
| Galileo | 28 August 1993 |
The story
Ida is an S-type main-belt asteroid found by Johann Palisa in 1884. Galileo passed it at 2,400 km on 28 August 1993. About 60 km long, elongated, full of craters and roughly 2 billion years old.
In Galileo’s images a small moon was found circling Ida: Dactyl, picked out by Ann Harch’s analysis in 1994. It was the first time an asteroid’s moon had been found; hundreds of binary asteroids are known today.
Missions
- Galileo (NASA, 1993): the flyby and the discovery of Dactyl
Colony note
A long, old body; a mining outpost.
What probes bring back
- Galileo passed on 28 August 1993; in the images (1994) the first moon of an asteroid was found: Dactyl.
- About 60 km long, an old, heavily cratered S-type; its surface is roughly 2 billion years old.