* Astronomy

The Orbital Test Vehicle is scheduled to launch from the Cape Canaveral Air Force Station between 23:52-00:01 GMT, 22 - 23 April, 2010.

T-0:00:02.7   Engine Start: The Russian-designed RD-180 main engine is ignited.
T+0:00:01.1  Liftoff: The Atlas 5 vehicle, designated AV-012, lifts off from Complex 41 at Cape Canaveral Air Force Station, Florida.
T+0:03:39     Nose Cone Jettison: The payload fairing that protected the X-37B spacecraft during launch is separated.
T+0:03:44     Forward Load Reactor Jettison: The Forward Load Reactor deck that supported the payload fairing's structure to Centaur upper stage is released five seconds after the shroud's jettison.
T+0:04:24     Main Engine Cutoff: The first stage's RD-180 engine shuts down after completing its burn during the Atlas 5 launch.
T+0:04:30     Stage Separation: The Common Core Booster first stage of the Atlas 5 rocket separates from the Centaur upper stage.
T+0:04:40     Centaur RL10 engine ignition 1: First burn.
T+0:17:18     Centaur engine cutoff 1:
T+0:20:00     Classified

Source United Launch Alliance.

Blastoff of the unmanned X-37B space plane from Kennedy Cape Canaveral Air Force Station in Florida Space Centre was delayed until Thursday, April 22, to allow Discovery to return to earth at the nearby Kennedy Space Centre. With many of its features kept secret, the project has sparked speculation that the little Orbital Test Vehicle is the space version of the US Predator drone.
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After a decade of development, the Air Force this month plans to launch a robotic spacecraft resembling a small space shuttle to conduct technology tests in orbit and then glide home to a California runway.
The ultimate purpose of the X-37B Orbital Test Vehicle and details about the craft, which has been passed between several government agencies, however, remain a mystery as it is prepared for launch April 19 from Cape Canaveral, Florida.
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