SpaceX is thought to be focusing on static friction in an engine throttle valve as the prime suspect for the loss of the Falcon 9 first stage during the third attempt at recovering the booster.

United Launch Alliance CEO Tory Bruno says his choice of planning to reuse only the BE-4 engines – not the entire first stage – of the company’s new Vulcan rocket was driven purely by the economics.

United Launch Alliance CEO Tory Bruno says Aerojet Rocketdyne’s claim of delivering an AR-1 rocket engine capable of operating on the Atlas V or Vulcan vehicles by 2018 is “ridiculous.”

"These finding have implications for planetary protection policies for future landed spacecraft," according to the Nature Geoscience report. "Cl-bearing brines are very corrosive and this may have implications on spacecraft design and surface operations."

The flight of Apollo 13 in April 1970 was one of the most dramatic events in the history of human spaceflight –- and ultimately one of NASA’s finest hours. For three days, the lives of three astronauts who had been bound for the third lunar landing mission hung in the balance.

This new rocket is the company’s path to substantially reduce its cost to launch — a critical factor as the company’s monopoly over national security launches is eroding — and compete against SpaceX.

Our roundup of the top stories in aerospace and defense from the last two weeks.

The space shuttle was a magnificent machine, the most capable spaceship ever built. It was also a fragile monster that required an expensive standing army to fly, and punished the slightest inattention to detail in its preparation and operation with fatal results.