Phobos:
- Diameter: 22.4 km (13.9 miles)
- Orbit:
- Average Distance from Mars: 9,377 km (5,827 miles)
- Orbital Period: 7.6 hours
- Composition: Likely composed of carbonaceous chondrite material.
- Surface Features: Heavily cratered, with a prominent crater named Stickney.
- Movement: Phobos is slowly spiraling inward toward Mars.