fysdt sends this quote from a Reuters report: "An unmanned Atlas 5 rocket blasted off from Cape Canaveral Air Force Station on Saturday to put the first satellite of the Defense Department's new missile-warning system into orbit. Tucked inside the rocket's nosecone was the $1.3 billion Space-Based Infrared Systems (SBIRS) Geo-1 spacecraft, built by Lockheed Martin and Northrop Grumman. The satellite, the first of four scheduled for launch over the next five years, is intended to provide the US military with early notice of missile launches and other reconnaissance services. The $17.6 billion SBIRS constellation, which includes sensors on host satellites, will augment and eventually replace the military's Defense Support Program satellites, which have been operating since 1970. The satellites scour the planet for heat trails produced by flying rockets and missiles."