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Six nations have placed lunar orbiters since 2007 — a 4× increase in 15 years.
| Attribute | 🇺🇸 Lunar Reconnaissance Orbiter (LRO)Active · Last updated 2026-06-01 Trust: Agency-primaryⓘ Last verified Remove × | ||
|---|---|---|---|
| Agency | NASA | NASA | NASA |
| Status | Deorbited | Active | Mission Complete |
| Mission type | Orbiter | Orbiter | Impactor |
| Launch date | 1998-01-06 | 2009-06-18 | 2009-06-18 |
| End date | 1999-07-31 | Active | 2009-10-09 |
| Orbit | 100 km circular polar orbit (lowered to 15-30 km for extended mission) | Polar low lunar orbit ~50 km (average) | Elliptical shepherding orbit; impacted Cabeus crater |
| Mass | 158 kgas of [1]One of the smallest and lowest-cost ($63M) NASA lunar orbiters | 1,916 kgas of [1]Includes Diviner, LOLA, LROC, MiniRF, LAMP, LEND, CRaTER instruments ↑ Heaviest | 891 kgas of [1]LCROSS + Centaur upper stage (2,366 kg total impact); Centaur impacted first |
| Instruments | 5 instrumentsas of [1] | 7 instrumentsas of [1] | 9 instrumentsas of [1] ↑ Most instruments |
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| Outcome | A low-cost ($63M) NASA Discovery mission that made one of the most important lunar discoveries of the late 20th century: strong evidence for water-ice at both poles. Deliberately impacted the lunar south pole at mission end; no detectable water plume was observed, but this was attributed to unfavorable geometry. | NASA's comprehensive lunar scout, now 16+ years in orbit. LRO has produced the most detailed maps of the lunar surface ever made, identified water-ice at the poles, and characterized the radiation environment for future crewed missions. Its LROC camera system imaged the Apollo landing sites, Chinese Chang'e landers, and recent commercial missions including IM-1 Odysseus. | NASA's low-cost ($79M) impactor mission co-launched with LRO. The Centaur upper stage struck Cabeus crater on October 9, 2009, ejecting a plume of material that LCROSS analyzed as it flew through it before also impacting. This definitively confirmed water-ice in permanently shadowed craters — one of the most important planetary science results of the 2000s. |
All 11 lunar orbital missions with primary-source citations from NASA, ESA, JAXA, ISRO, CNSA, and NASA NSSDCA. Coverage spans Clementine (1994) through LRO (active 2026). Pure URL state — bookmark or share the link and the comparison reproduces exactly.