TheLunar Precursor Robotic Program (LPRP) is aNASA program that usesrobotic spacecraft to prepare for futurecrewed missions to theMoon. The program gathers data such as lunar radiation, surface imaging, areas of scientific interest, temperature and lighting conditions, and potential resource identification.[1][2]
Two LPRP missions, theLunar Reconnaissance Orbiter (LRO) and the Lunar Crater Observation and Sensing Satellite (LCROSS), were launched in June 2009.[3] The lift-off aboveCape Canaveral Air Force Station inFlorida on June 18, 2009, was successful. The uncrewedAtlas V rocket launched the two space probes towards the Moon, where they will provide a 3D map and search for water in conjunction with theHubble Space Telescope,[4][5] launching on June 17, 2009.
This lunar program marked the first United States mission to the Moon in over ten years.[6]Neil Armstrong's first step on the Moon occurred on July 20, 1969, and this launch was 32 days before its 40th anniversary.[7] TheLRO entered a low orbit around the Moon, while the LCROSS mission performed a "swing-by" and entered a different orbit to set up acollision with the Moon's surface several months later. The projected lunar impact of theCentaur and LCROSS spacecraft was on October 9, 2009, at 11:30 UT (7:30 a.m. EDT, 4:30 a.m. PDT), ± 30 minutes. The plume from the Centaur impact was predicted by NASA to be visible through telescopes withapertures as small as 10 to 12 inches (300 mm).[5][8]
Initially, the LPRP program was a part of theScience Mission Directorate of NASA (SMD) and was called the Robotic Lunar Exploration Program (RLEP). Management of the RLEP program was assigned toGoddard Space Flight Center (GSFC) in February 2004. At that time, the Program's goal was to "...initiate a series of robotic missions to the Moon to prepare for and support future human exploration activities."[9]
In 2005, responsibility for RLEP was moved to NASA's Exploration Systems Mission Directorate (ESMD) and management was assigned to theAmes Research Center (ARC). In 2006, the program was renamed the Lunar Precursor Robotic Program and management responsibility was reassigned to theMarshall Space Flight Center (MSFC). TheUS$583 million space mission comes equipped with a $504 million 4,200 pounds (1,900 kg) LRO space probe and a $79 million LCROSS satellite.[10]
TheLunar Reconnaissance Orbiter (LRO) is the first mission of the LPRP program. Management of the LRO was assigned toGoddard Space Flight Center (GSFC) in 2004. The LRO launched on anAtlas V 401 rocket fromCape Canaveral Air Force Station[11] on June 18, 2009, at 5:32 p.m. EDT (2132 GMT). The planned liftoff at 5:12 p.m. EDT (2112 GMT) was delayed by 20 minutes due to thunderstorms.[10] The LRO was scheduled to orbit the Moon for one year, gathering high-resolution images of the lunar surface that would allow the creation of detailed maps. The LRO's goals included finding safe landing sites for human visits to the Moon, identifying lunar resources, studying the lunar radiation environment, and providing a 3D map of the Moon's surface to allow astronauts to return to the Moon by 2020. The LRO carried seven maininstruments, including the Cosmic Ray Telescope for the Effects of Radiation (CRaTER), the Diviner Lunar Radiometer Experiment (DLRE), the Lyman-Alpha Mapping Project (LAMP), the Lunar Exploration Neutron Detector (LEND), the Lunar Orbiter Laser Altimeter (LOLA), the Lunar Reconnaissance Orbiter Camera (LROC), and the Miniature Radio Frequency radar (Mini-RF).[7][12][13]
The Lunar Crater Observation and Sensing Satellite (LCROSS) mission is to be launched with the LRO. It was selected as a secondary payload in 2006, and management of the program was assigned toAmes Research Center (ARC). The mission will explore a permanently shadowed region of a lunar pole by crashing the 2,300 pounds (1,000 kg) spentCentaur rocket upper stage of theAtlas V launch vehicle into a dark crater. The composition of the ejecta plume will be observed by a shepherding spacecraft, which will itself crash-land 4 minutes later, creating a second plume. NASA expects the impact velocity will be over 9,000 km/h (5,600 mph). The ejecta plume will weigh in the order of 350 tons (317 metric tons) and rise 6 miles (9.7 km) from the surface.[14][15]
The Lunar Atmosphere and Dust Environment Explorer (LADEE) launched on September 7, 2013.[16] LADEE studied thelunar exosphere and dust in the Moon's vicinity.
For a hypotheticalInternational Lunar Network, NASA and international partners planned to land two stations on the lunar surface.[17] Their objective was to establish a robotic set of geophysical monitoring stations on the surface and, eventually, in lunar orbit as well.[18]
The Lunar Mapping and Modeling project is using the obtained data to develop detailed topographic maps of the lunar surface that support lunar science, exploration, commercial, educational, and public outreach activities.[19] In addition, solar radiation levels will be mapped and modelled. These integrated data will be used by NASA to make decisions about, for example, lunar outpost designs.
