On March 3, 2007, the Moon will be at its descending node, crossing the Earth’s orbital plane, moving southward. The Moon will also be at 100% illumination, or at full Moon, during the node crossing. These are the requirements for a lunar eclipse to occur, and this year viewers across the continental United States will get two opportunities for viewing one. The lunar eclipse occurring this month will favor viewers from the eastern half of the United States, while the second lunar eclipse, occurring at the end of August, will favor the western half of the United States. More information on the August eclipse will appear in the summer issue of Science Scope.