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Gaspra

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Gaspra
Credit: NASA / JPL Public Domain — NASA Media Usage Guidelines
ASTEROID

Gaspra

The first asteroid ever visited by a spacecraft — Galileo flyby, October 1991.

Orbits Sun

Physical Properties

6 km
7.042 h
0.22

Orbit

Sun
2.21 AU
0.173
4.1°
3.29 yr

Gallery

Hand-picked mission imagery of Gaspra sourced from NASA and partner archives. Click any photo for full resolution and source attribution.

Gaspra, Deimos, and Phobos Comparison
Gaspra, Deimos, and Phobos Comparison NASA / JPL · Public Domain u2014 NASA Media Usage Guidelines
Gaspra - First Image
Gaspra – First Image NASA / JPL
Highest Resolution Gaspra Mosaic
Highest Resolution Gaspra Mosaic NASA / JPL
Gaspra - Highest Resolution Mosaic
Gaspra – Highest Resolution Mosaic NASA / JPL

Imagery on this page is provided by the original mission teams. Full attribution terms: Image Rights & Credits.

Sources & Further Reading

Numerical values (radius, mass, orbital elements, temperatures) are drawn from NASA NSSDC Planetary Fact Sheets, JPL Horizons, and the JPL Small-Body Database. Last refreshed: 2026-05-28 19:14:36.

951 Gaspra is an S-type main-belt asteroid that on 29 October 1991 became the first asteroid ever visited by a spacecraft, when NASA’s Galileo flew past it on its way to Jupiter.