# LCROSS

> NASA monitoring spacecraft and lunar impactor

**Wikidata**: [Q459399](https://www.wikidata.org/wiki/Q459399)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/LCROSS)  
**Source**: https://4ort.xyz/entity/lcross

## Summary
The Lunar Crater Observation and Sensing Satellite (LCROSS) was a NASA space probe and lunar impactor designed to confirm the presence of water ice on the Moon. Launched on June 18, 2009, the mission culminated on October 9, 2009, when the spacecraft intentionally impacted the lunar crater Cabeus. It operated as a "shepherding spacecraft" that guided the spent Centaur upper stage into the moon before flying through the resulting ejecta plume to analyze its composition.

## Key Facts
- **Classification**: Space probe (unmanned robotic spacecraft exploring beyond Earth orbit) and lunar impactor.
- **Launch Date**: June 18, 2009, at 21:32:00 UTC.
- **Launch Site**: Cape Canaveral Space Launch Complex 41.
- **Launch Vehicle**: Atlas V 401 (serial number AV-020), provided by United Launch Alliance.
- **Operator**: NASA Ames Research Center.
- **Mission End**: October 9, 2009, at 11:35:34 UTC.
- **Final Location**: Cabeus crater, Moon (coordinates: -84.719°, -49.61°).
- **Mass (Launch Weight)**: 891 kilograms.
- **Dimensions**: 3.3 meters wide by 2.0 meters high.
- **Power Source**: Spacecraft solar array (600 watts) and lithium-ion batteries.
- **Spacecraft Bus**: Eagle-0.

## FAQs
### Q: What was the primary mission of LCROSS?
A: LCROSS was designed to search for water ice on the Moon. It accomplished this by crashing into the lunar surface to excavate subsurface material, which it analyzed before its own destruction.

### Q: How did LCROSS end its mission?
A: The mission concluded with a "lunar impact" event. The spacecraft intentionally crashed into the Cabeus crater near the Moon's south pole on October 9, 2009.

### Q: Who built the LCROSS spacecraft?
A: Northrop Grumman Aeronautics Systems manufactured the spacecraft, while the payload was developed by NASA's Ames Research Center.

### Q: What was the LCROSS "Shepherding Spacecraft"?
A: This refers to the main LCROSS probe. Its role was to guide the spent Centaur rocket stage to the impact site, observe the crash, and fly through the resulting plume to collect data before impacting the moon itself.

## Why It Matters
LCROSS was a critical mission in lunar science, providing definitive confirmation of water ice on the Moon. By targeting the permanently shadowed Cabeus crater, the mission proved that valuable resources exist in these sun-shy regions. This discovery transformed the understanding of lunar geology and has significant implications for future deep-space exploration, as water ice can be used to create breathable oxygen and rocket fuel. As a relatively low-cost "secondary payload" mission (launched with the Lunar Reconnaissance Orbiter), LCROSS demonstrated how focused, impact-based investigations could yield high-value scientific data, paving the way for future resource-utilization missions under NASA's Artemis program.

## Notable For
- **Water Discovery**: Successfully confirmed the presence of water ice in a permanently shadowed lunar crater.
- **Dual-Impact Strategy**: Utilized a two-stage impact strategy, first using the Centaur upper stage to create a plume, followed by the spacecraft's own impact after data collection.
- **Rapid Mission Cycle**: Completed its entire mission profile—from launch to final impact—in less than four months.
- **Cost-Effectiveness**: Served as a secondary payload to the LRO, maximizing scientific return relative to cost.
- **Precision Targeting**: Successfully navigated to impact a specific, challenging target (Cabeus crater) near the lunar south pole.

## Body
### Mission Profile and Launch
LCROSS was developed and operated by NASA's Ames Research Center. It was launched on June 18, 2009, atop an Atlas V 401 rocket (AV-020) from Cape Canaveral. Although often associated with the Lunar Reconnaissance Orbiter (LRO), LCROSS was a distinct mission with the specific objective of lunar impact and sensing.

### Spacecraft Design and Specifications
The spacecraft, based on the Eagle-0 bus, had a launch mass of 891 kg and a dry weight of 585 kg. It measured 3.3 meters in width and 2.0 meters in height. Power was supplied by a 600-watt solar array and lithium-ion batteries. The structure was designed to carry the Near-Infrared Spectrometer, Visible Spectrometer, and cameras needed to analyze the impact plume.

### The Lunar Impact
On October 9, 2009, LCROSS executed its final maneuver. The mission involved the Centaur upper stage striking the lunar surface first to excavate material. The Shepherding Spacecraft then flew through the resulting plume, analyzing it for water and other compounds before impacting the surface itself at the Cabeus crater (coordinates -84.719, -49.61). The mission was officially dissolved upon this impact.

### Identifiers and Classifiers
- **COSPAR ID**: 2009-031B
- **NAIF ID**: -18
- **Alternate Names**: LCROSS Shepherding Spacecraft, LCROSS S-S/C.

## References

1. [Source](https://www.nasa.gov/pdf/360020main_LRO_LCROSS_presskit2.pdf)
2. Jonathan's Space Report
3. [Source](https://space.skyrocket.de/doc_sdat/lcross.htm)
4. [Source](https://pds-geosciences.wustl.edu/lunar/lcross-e_l-mir1-2-raw-v1/lcro_0001/catalog/mission.cat)
5. Locating the LCROSS Impact Craters
6. Freebase Data Dumps. 2013
7. [Source](https://www.timeanddate.com/date/durationresult.html?m1=06&d1=18&y1=2009&m2=10&d2=09&y2=2009&h1=21&i1=32&s1=00&h2=11&i2=35&s2=34)
8. [LRO/LCROSS Press Kit v2](http://www.nasa.gov/pdf/360020main_LRO_LCROSS_presskit2.pdf)
9. [Source](https://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/req/naif_ids.html)