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The Fall and Rise of 'X' - Universe Today
[/caption] They are at the very edge of current U.S. technological capabilities; one is a supposedly mothballed technology test-bed, the other a super-secret space plane that is currently on orbit – but set to land soon. They are the X-planes, experimental spacecraft that are proving out concepts and capabilities whose beginnings can be traced to … Continue reading "The Fall and Rise of ‘X’"