Observers watch Virgin Galactic's SpaceshipTwo take off for a suborbital test flight of the VSS Unity in Mojave, Calif. The company marked a major milestone Thursday as Unity made it to a peak height of more than 51 miles, meeting the Federal Aviation Administration's definition of spaceflight.
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A photo released by Virgin Galactic shows a badly injured SpaceShipTwo pilot Peter Siebold drifting under his parachute after last October's accident that destroyed the spacecraft during a test flight.
Mark Greenberg/Virgin Galactic
In a photo released by Scaled Composites, Michael Alsbury, who was killed while co-piloting the test flight of Virgin Galactic SpaceShipTwo on Friday, Oct. 31, 2014, is shown.