Page "Deep Space 1" Paragraph 5

The Autonav system can also be used in reverse, tracking the position of bodies relative to the spacecraft.

This is used to acquire targets for the scientific instruments.

The spacecraft is programmed with the target's coarse location.

After initial acquisition, Autonav keeps the subject in frame, even commandeering the spacecraft's attitude control.

The next spacecraft to use Autonav was Deep Impact.