Lunar Farside
Tidally locked in synchronous rotation , the Moon always presents its familiar nearside to denizens of planet Earth . From lunar orbit, the Moon's farside can become familiar, though. In fact this sharp picture , a mosaic from the Lunar Reconnaissance Orbiter's wide angle camera, is centered on the lunar farside. Part of a global mosaic of over 15,000 images acquired between November 2009 and February 2011, the highest resolution version shows features at a scale of 100 meters per pixel. Surprisingly, the rough and battered surface of the farside looks very different from the nearside covered with smooth dark lunar maria. A likely explanation is that the farside crust is thicker , making it harder for molten material from the interior to flow to the surface and form dark, smooth maria .