
Surveyor 5
Surveyor 5 — a soft-lander that survived a mid-flight helium leak (launched 8 September 1967) to touch down in the Sea of Tranquility. There it made the first in-situ chemical analysis of another world, showing the lunar soil was basaltic.
Key facts
Mission & specifications
Mission
- Operator
- NASA / JPL
- Launched
- September 8, 1967
- Status
- Completed
Trajectory
- Distance from the Sun
- 1.01 AU
- Distance from Earth
- 433,824 km
- Distance from Venus
- 0.603 AU
Mission
Surveyor 5 turned near-disaster into one of the programme's most important results. Launched on 8 September 1967, it developed a serious helium leak in its propulsion system on the way to the Moon. Engineers improvised a radically revised descent plan on the fly, firing the engines differently to compensate, and against the odds the craft landed safely in the Sea of Tranquility. There it carried out the programme's scientific coup: an alpha-particle instrument that bombarded the soil and read the particles that scattered back made the first in-situ chemical analysis of the surface of another world. The result showed the lunar soil was basaltic, akin to volcanic rock on Earth — the first direct chemistry of the Moon, and a preview of what Apollo's samples would later confirm.
- 1967MoonLander
Made the first in-situ chemical analysis of the surface of another world, showing the Moon's soil was basaltic.
Images

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