Maybe there won’t be a GPS gap after all. A Defense Department report to Congress last October 31 suggested that roughly 19 GPS satellites had little margin for further system failure. Losing any single system on these spacecraft could make them fail. If this happened with more than seven birds, there could be a coverage gap in GPS. Now, some of that danger has lessened with the launch yesterday of a GPS satellite from Space Launch Complex-17A, Cape Canaveral Air Force Station, Fla., at 4:34 a.m. (EDT) March 24. According to the Air Force, after a one-hour, eight-minute flight, the 47th successful GPS satellite launched by a Delta II achieved orbit. Good news for everyone on the water who isn’t using their sextant or loran to find their way. Launch photo by Carleton Bailie, courtesy United Launch Alliance.