Aerospace engineers and enthusiasts the world over are talking about NASA’s plan to crash Ebb and Flow, two spacecraft on a moon-mapping mission throughout 2012, into the moon’s surface. Not since the Curiosity rover landed on Mars has the mil/aero industry been so focused on and excited about news from NASA.
Ebb and Flow are part of NASA’s roughly $500 million Gravity Recovery and Interior Laboratory (GRAIL) program to study and map the moon’s structure. Data acquired and provided by the Ebb and Flow space probes are expected to provide a greater understanding of the moon, including the structure of the lunar crust, lithosphere, impact basin sub-surfaces, the deep interior, and even the inner core.
Ebb and Flow have worked in tandem in orbit—two participants performing a well-choreographed lunar dance—throughout all of 2012. A NASA spokesperson describes their unique functionality: “As they fly over areas of greater and lesser gravity, caused both by visible features such as mountains and craters and by masses hidden beneath the lunar surface, they will move slightly toward and away from each other. An instrument aboard each spacecraft [measures] the changes in their relative velocity very precisely, and scientists translate this information into a high-resolution map of the Moon’s gravitational field.”
Launched in September 2011 and gathering information in orbit since 1 January 2012, Ebb and Flow revealed to NASAs’ GRAIL team that the moon’s crust is both thinner and more fractured than previously believed. As 2012 comes to a close, this geek thinks it is perhaps fitting that Ebb and Flow’s year-long journey comes to an end; and, if they’ve got to go out, then why not with a bang?