Secret U.S. Space Mission

A spectacular space launch - shrouded in secrecy.

Inside this Atlas 5 rocket is the experimental Orbital Test Vehicle 2.

The prototype miniature space shuttle blasted off from the U.S.'s Cape Canaveral on a classified mission on Saturday.

As with a previous test flight, what the OTV-2 will do in orbit, as well as any of the cargo or experiments that are onboard, is confidential.

This computer animation shows how the spacecraft will operate.

Once fully operational, the Air Force said the project could be used for a variety of missions, including reconnaissance, in space service and repair of satellites, and demonstrating new technologies.

The OTV-2's mission is expected to last around nine months.