Shuttle Atlantis unwrapped ahead of public debut

Fueled segments of the solid rocket boosters that will lift off on the first flight of NASA’s Space Launch System have arrived at the Kennedy Space Center in Florida, but officials will hold off on stacking the boosters until the SLS core stage completes a crucial test-firing later this year.

Sixty years ago Monday, a 27-year-old Russian test pilot named Yuri Gagarin strapped into a Vostok capsule in Central Asia and rode into orbit atop a launcher derived from a Soviet nuclear missile, becoming the first human to travel into the void of space. Twenty years later, in 1981, the era of reusable spacecraft dawned with the first launch of NASA’s space shuttle.

SpaceX’s next Falcon 9 rocket is being readied for liftoff Aug. 14 on a space station resupply run. The two-stage rocket completed a hold-down engine firing Thursday at launch pad 39A at NASA’s Kennedy Space Center in Florida.