Luna 20, a Soviet mission than landed on the Moon 50 years, sits quietly on the lunar surface today, as shown in this photograph from Lunar Reconnaissance Orbiter (arrow). It was a repeat of the mission plan for Luna 18, which had crashed on the Moon a few months earlier. Luna 20 scooped up about 55 grams of lunar dirt and pebbles and returned them to Earth for analysis. Russia plans to resurrect its Luna program this year, with Luna 25. [NASA]