Lunar rock sample. This rock sample was collected during the 1972 Apollo 16 mission by John W. Young, the mission commander. It is a breccia, a type of rock formed from surface material smashed and melted by meteoric impacts. Like all breccias found on the lunar highlands, it is very old; it formed 3.9 billion years ago, which is older than 99.99% of surface rocks on Earth. It weighs 128 grammes. Photographed at NASA's Johnson Space Research Center, Houston, Texas, USA.