Caption: Asteroid 243 Ida and its moon Dactyl.

Features:

1. This is a false-color image of Ida taken on a flyby by the Galileo spacecraft (1989--1995-arrival--2003) on its way to Jupiter.

   It was just a fortuitous coincidence that Ida was on the trajectory of the Galileo spacecraft (19891995-arrival--2003).

2. The colors were chosen to indicate possible differences in surface composition. Blue may indicate iron bearing minerals.

3. North on Ida is at 1:00 o'clock (in clock position). But does this mean north on the celestial sphere or north as the axis of rotation with the direction of rotation given by a right-hand rule? The NASA caption doesn't say, but I suspect the later.

4. Ida, like most smaller asteroids, is NOT round. Its self-gravity is insufficient to pull it into a spherical shape against the rigid-body electromagnetic force of its solid materials and the centrifugal force due to its rotation.

5. There are still relatively asteroids that have been imaged up close. But we certainly have lots images of those asteroids that have intentionally visited by spacecraft: e.g., 1 Ceres ⚳, 4 Vesta ⚶, and 433 Eros (see Wikipedia: List of minor planets that have been visited by spacecraft).

   The number visited asteroids will probably increase with time.