... Inside Mars . ... From orbit, the Mars Global Surveyor (MGS) spacecraft has recorded detailed images of the red planet since July 1997. ... Many of these glass beads were present in lunar soil samples returned to Earth by the Apollo missions. ... Because Mercury orbits so close to the Sun, it is never seen far from the Sun, and so is only visible near sunrise or sunset. If trailing the Sun, Mercury will be visible for several minutes before it follows the Sun behind the Earth. ...