* ... " The robotic X-37B space plane launched atop a United Launch Alliance Atlas V rocket today (May 20) at 11:05 a.m. EDT (1505 GMT) from Florida's Cape Canaveral Air Force Station. You can see a video of the X-37B space plane's launch at http://bit.ly/1dmH4qA
Most details about the space plane's orbital activities are classified, so it's unclear what exactly the X-37B will be doing as it zooms around Earth, or how long it will remain aloft. But Air Force officials have said that mission number four — known as Orbital Test Vehicle-4 (OTV-4) — will concentrate less on the X-37B itself and more on the gear the spacecraft is carrying to orbit.
... Also on board the Atlas V were 10 miniscule "cubesats," including the LightSail solar sail that was developed by the nonprofit Planetary Society. LightSail aims to prove out key solar-sailing technology ahead of a more ambitious orbital trial next year.
The Air Force owns two X-37B spacecraft, both of which were built by Boeing's Phantom Works division. Each space plane is just 29 feet long by 9.5 feet tall (8.8 by 2.9 meters), with a wingspan of 15 feet (4.6 m) and a payload bay the size of a pickup-truck bed. To put those dimensions into perspective, both X-37Bs could fit inside the payload bay of NASA's now-retired space shuttle orbiter.
The X-37B launches vertically and lands horizontally, on a runway, as the space shuttle did.
The secrecy surrounding X-37B missions has led to speculation in some quarters that the craft is some sort of space weapon — that it's designed to inspect and/or cripple hostile nations' satellites, for example. But Air Force officials have long refuted that notion, saying the X-37B is simply testing out technologies for reusable vehicles and future spacecraft. ..."