As our nearest neighbor, the Moon is a natural laboratory for investigating fundamental questions about the origin and evolution of the Earth and the solar system. With the Lunar Reconnaissance Orbiter (LRO), NASA has returned to the Moon, enabling new discoveries and bringing the Moon back into the public eye. LRO launched on an Atlas V rocket on June 18, 2009, beginning a four-day trip to the Moon. LRO spent its first three years in a low polar orbit collecting detailed information about the Moon and its environment. After this initial orbit, LRO transitioned to a stable elliptical orbit, passing low over the lunar south pole.
While in orbit, LRO observations have enabled numerous groundbreaking discoveries, creating a new picture of the Moon as a dynamic and complex body. These developments have set up a scientific framework through which to challenge and improve our understanding of processes throughout the solar system.
The Lunar Reconnaissance Orbiter (LRO) orbits the Moon from pole to pole, which enables some instruments aboard the spacecraft to image the entire surface of the Moon over the course of a lunar day (28 Earth days). The Lunar Reconnaissance Orbiter Camera (LROC), one of the seven instruments aboard LRO, has provided this high-resolution map of the Moon. The Lunar Reconnaissance Orbiter Camera is made up of a Narrow Angle Camera, which is used to image the Moon in sub-meter scale resolution, and a Wide Angle Camera (WAC), which images the Moon at a much lower resolution, but can image more of the Moon's surface at one time. The visible light image shown here is a global mosaic of over 15,000 images acquired between November 2009 and February 2011 by the LROC WAC camera.
The near side of the moon has light areas referred to as
Lunar Highlands and dark areas called Maria. The maria are lower in
altitude than the highlands and filled with dark solidified lava from
when the moon was volcanically active. Both areas are littered with
craters, as the Moon’s surface is very old and has had time to
accumulate craters. While the far side of the moon is also covered with
craters, there are fewer maria present. More than 70 spacecraft have gone
to the Moon and 12 astronauts have actually had the chance to walk on
the surface of the Moon.