Ebb and Flow are no more

The twin spacecraft of NASA’s GRAIL mission have completed their final rocket burns. Their pre-planned lunar impact occurred at about 2:28 p.m. PST (5:28 EST). Ebb and Flow completed their final rocket burns and impacted the moon at 2:28 p.m. PST (5:28 EST).

The two probes hit a mountain near the lunar north pole, bringing their successful prime and extended science missions to an end. The two probes were sent purposely into the moon because they no longer have enough altitude or fuel to continue science operations.

GRAIL's final resting place on the moon will be in shadow at the time of impact, so no video documentation of the impacts was expected. GRAIL data are allowing scientists to learn about the moon's internal structure and composition in unprecedented detail.