Lunar Reconnaissance Orbiter

Lunar Reconnaissance Orbiter
Name	Lunar Reconnaissance Orbiter
Mission type	Lunar orbiter
Operator	NASA / Goddard Space Flight Center
COSPAR ID	2009-031A
SATCAT	35315
Mission duration	Planned: 1 year, Elapsed: 15 years, 1 month, 19 days
Spacecraft	LRO
Manufacturer	Goddard Space Flight Center
Launch mass	1,916 kg (4,224 lb)
Power	1850 W
Launch date	June 18, 2009, 21:32 UTC
Launch rocket	Atlas V 401
Launch site	Cape Canaveral SLC-41
Last contact	Ongoing
Orbit reference	Selenocentric orbit
Orbit regime	Polar orbit
Orbit periapsis	50 km (31 mi)
Orbit apoapsis	50 km (31 mi)
Orbit period	113 minutes
Orbit inclination	90°
Apsis	selene
Insignia caption	Mission insignia

Lunar Reconnaissance Orbiter is a NASA robotic spacecraft currently orbiting the Moon in a low-altitude polar orbit. Launched in 2009, its primary mission was to collect detailed data to aid in planning future human and robotic missions to the lunar surface. The mission has far exceeded its original one-year operational timeline, providing an unprecedented, continuous record of the Moon's surface and environment.

Overview

The mission is managed by NASA's Goddard Space Flight Center in partnership with scientists from institutions like the University of Arizona and Johns Hopkins University. It was launched alongside the Lunar Crater Observation and Sensing Satellite (LCROSS) impactor mission aboard an Atlas V rocket from Cape Canaveral Space Force Station. As a key component of NASA's Vision for Space Exploration and later the Artemis program, its data is fundamental for selecting safe landing sites and understanding lunar resources.

Mission objectives

Primary objectives focused on scouting for future human exploration. This included characterizing the lunar radiation environment, creating high-resolution topographic maps, and identifying potential surface resources like water ice in permanently shadowed regions. Specific goals were to map the surface in extreme detail, measure temperatures and ultraviolet albedo, and probe the polar regions of the Moon for evidence of volatiles. The data was also intended to support the goals outlined in the NASA Authorization Act of 2005.

Spacecraft design and instruments

The spacecraft bus was built by Goddard Space Flight Center and carries a sophisticated suite of seven instruments. The Lunar Reconnaissance Orbiter Camera (LROC) system, led by Mark Robinson of Arizona State University, captures high-resolution black-and-white and moderate-resolution color images. The Lunar Orbiter Laser Altimeter (LOLA) provides precise topographic data, while the Diviner Lunar Radiometer Experiment, led by David Paige of UCLA, maps surface temperatures. Other instruments include the Lyman-Alpha Mapping Project (LAMP), which peers into shadows, the Lunar Exploration Neutron Detector (LEND), the Cosmic Ray Telescope for the Effects of Radiation (CRaTER), and the Miniature Radio Frequency (Mini-RF) radar.

Mission profile and timeline

Launched on June 18, 2009, the spacecraft entered an elliptical commissioning orbit around the Moon four days later. After initial instrument checks, it transitioned to its primary circular mapping orbit in September 2009. The nominal science mission lasted one year, after which NASA transitioned the mission to an extended science phase focused on long-term monitoring and targeted observations. Key events have included imaging the Apollo program landing sites, supporting the GRAIL and LADEE missions, and continually mapping changing illumination conditions at the poles.

Scientific discoveries and results

The mission has revolutionized lunar science, providing the most detailed atlas of the Moon ever created. It has confirmed the presence of water ice in permanently shadowed craters near the lunar south pole, such as Shackleton Crater. LROC images have documented recent geologic activity, identified potential lava tubes, and provided precise coordinates for features like the Mons Mouton plateau. Data from Diviner and LOLA have been used to create global temperature and slope maps, critical for engineering and science. Its observations were vital for selecting candidate landing regions for the Artemis program.

Legacy and impact

The mission's enduring legacy is its foundational role in the return of humans to the Moon. Its data archives are an indispensable resource for the global scientific community and commercial entities. The mission directly informed the selection of landing sites for missions like Chandrayaan-3 and the planned Artemis 3 crewed landing. Its long-term data set on seasonal changes and impact cratering rates provides a unique record for comparative planetary science, influencing studies of other airless bodies like Mercury and the moons of Jupiter.

Category:NASA space probes Category:Exploration of the Moon Category:2009 in spaceflight Category:Spacecraft launched in 2009