NASA’s Mars Odyssey spacecraft completed its 60,000th orbit of the Red Planet on June 23, 2015. When Odyssey launched in April 2001 with a goal of better understanding Mars’ environment, the Red Planet was generally thought to be dry, barren world; the mission transformed our understanding, discovering widespread subsurface water ice. Its continuous observations have also provided details about martian weather and radiation, crucial for planning future human missions, and it serves as a key communications relay for surface missions. The record-holder for the longest-operating spacecraft in orbit around another planet, the orbiter continues to return images and data: Just last month, it captured a first-of-its-kind panorama of the Arsia Mons volcano peeking above the early morning cloud tops.
