With the release of the official Announcement of Opportunity (AO) early in November, NASA has officially begun the competition to select its next low cost ($450M) Discovery program planetary mission. Because planetary scientists are free to propose missions to any destination in the solar system other than the sun and Earth, these competitions bring out the creativity in the planetary science program.
For the last two years, NASA has been the shy partner refusing to get on the dance floor, and Congress has been the aggressive partner insisting on a dance now. The dance is the continuing attempt by Congress to have NASA commit to a mission to explore Europa, and NASA’s attempts to delay a mission well into the 2020s.
In December, scientists announced the discovery of possible plumes of water being ejected from Jupiters’s moon Europa. If confirmed, Europa would be the second moon with confirmed plumes after Saturn’s moon Enceladus. Two Discovery mission proposals for Enceladus suggest the types of missions that may be proposed for Europa.