Mars Reconnaissance Orbiter (MRO) radar sensor, illustration. The MRO is using its Shallow Subsurface Radar instrument (SHARAD) to 'look' under the surface of Mars. The radar instrument will seek liquid or frozen water within the first few hundred metres (up to a kilometre) under the Martian surface. The MRO spacecraft was launched by NASA in August 2005, and arrived at Mars in March 2006. Since its arrival, it has used cameras, spectrometers and radar to study the planet's surface features and geology, including the rock layers (stratigraphy), and deposits of minerals and ice. It monitors the weather conditions and acts as a high-capacity telecommunications system to relay data back to Earth from other spacecraft and probes. Image published in 2005.