This undated artist rendering shows the twin Grail spacecraft
mapping the lunar gravity field. Cape Canaveral, FL (Florida
Today) -- Twin NASA spacecraft will crash deliberately into a
mountain on the moon today, ending a successful mission that is
shedding light on the evolution of the solar system's Each about
the size of compact washing machines, the Ebb and Flow
spacecraft are low on fuel, and they've finished a $496 million
mission aimed at making the most accurate gravitational map of
the moon to date. the spacecraft will be directed on a shallow
dive into a mile-high mountain near the moon's north pole - a
controlled crash-landing that will occur in the lunar night.
Expected velocity at impact is 3,760 mph. But don't expect
anything dramatic here on Earth. are not expecting a big splash
or a big explosion, OK?" said Maria Zuber, a professor of
geophysics at Massachusetts Institute of Technology and the
mission's principal scientific investigator. "These are two
small spacecraft ... with empty fuel tank