The past and future of America’s space arsenal intersected, briefly, in the summer of 2011. For two weeks in July, NASA’s Space Shuttle Atlantis roughly shared its Earth orbit with the Air Force’s X-37B, a 29-foot-long, highly maneuverable robotic spacecraft that entered service in early 2010 and has been cloaked in secrecy ever since. The X-37 was around 80 miles higher than the Shuttle, so it’s doubtful the four-person Atlantis crew, conducting the 135th and last Shuttle mission, ever saw the robotic craft. The X-37′s small size — barely a quarter the length of Atlantis — made a sighting even less likely.
Equally striking was the difference in cost between Atlantis and its tiny robotic compatriot. Atlantis cost more than $10 billion to design and build and around $500 million to launch on that one mission. The Boeing-built X-37 mini-shuttle set the taxpayers back an estimated $1 billion for development and construction and just $180 million to send into space. (All cost figures in this story are in today’s dollars.)
‘Small’ is the new watch-word for America’s orbital force. But small doesn’t mean less capable.
There are lots of things Atlantis could do that the X-37 cannot and vice versa, complicating any direct comparison. Both craft were designed to carry scientific and military payloads into orbit: Atlantis, with its school-bus-size cargo bay, emphasized carrying capacity; the X-37, optimized for endurance, has a bay the size of a pickup truck’s bed. Still, it’s almost unheard of for a major government technology to be cheaper than its immediate predecessor. Just ask the Air Force, with its $400 million F-22 fighters replacing F-15s that cost a quarter as much.Moreover, the X-37B is meant to be launched into space on short notice, remain in orbit for a year or more and return only when its fuel tanks finally run dry. After a few weeks or months of reconditioning, the mini-shuttle is ready to return to space atop an Atlas rocket. With its fleet of two X-37s, the Air Force can keep at least one in orbit at all times.
Because they had to support their human crews, Atlantis and her sister Space Shuttles could spend at most two weeks in orbit before their water and air supplies began to run out. Between flights the manned orbiters needed nine months of expensive reconditioning by Rockwell, the main Shuttle contractor. It would have taken a fleet of 18 Space Shuttles to ensure one was in space at all times, but NASA built only five of the massive spacecraft for a total program cost of more than $200 billion.
From huge, slow and expensive to tiny, speedy and cheaper, Atlantis’ and the X-37′s brief proximity last summer represented a passing-of-the-torch for the world’s leading space power. The era of big space missions is fading. “Small” is the new watch-word for America’s orbital force. But as the X-37 and a host of other new spacecraft demonstrate, small doesn’t mean less capable.
Tiny satellites, including relays, orbital cameras and other sensors, aren’t the only “faster-better-cheaper” tech transforming the American space force. So-called “pseudolites” — that is, relatively inexpensive robots, planes and airships operating in the very-high-but-not-quite-orbit upper atmosphere — are rapidly proliferating and taking the place of some old-school satellites.
The “smaller-is-better” space revolution wasn’t inevitable. It resulted from a complex interplay of politics and economics, plus a chain of engineering crises that claimed some careers and even a few lives. What follows is a brief recent history of America’s space force from the end of the Cold War to today, with a glimpse into the future as old spacecraft waste away and smaller, quicker, cheaper and more robotic systems take their place.
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