Rocket blasts off with missile-warning satellite

CAPE CANAVERAL, Florida (Reuters) - 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.

After a day's delay due to poor weather, the United Launch Alliance Atlas 5 booster lifted off at 2:10 a.m. EDT, soaring through clear blue skies out over the Atlantic Ocean.

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 U.S. 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.

"Geo-1 will bring the dawn of a new era in persistent overhead surveillance," Roger Teague, head of the U.S. Air Force's Infrared Space Systems Directorate, told reporters.

"These systems are so much more sensitive. We can see much more, much earlier, much sooner (and) many dimmer targets."

Over the next nine days, Geo-1's position will be tweaked so that it ends up in an orbit about 22,000 miles above the planet.

In addition to scanning for missile launches, Geo-1 has instruments that can home in on areas of interest for tactical reconnaissance, officials said.

The SBIRS network includes sensors on other satellites, already in orbit.

Geo-2, the second in the constellation, is expected to be ready to launch next year, said James Sponnick, mission operations director for United Launch Alliance, a Boeing-Lockheed Martin partnership that builds the Atlas rockets.

(Editing by Chris Wilson)