Video: Liftoff of Atlas 5 with X-37B on program’s fourth flight

SpaceX is still working on a new, safer helium tank design needed for launches with astronauts, and the debut of the company’s upgraded Falcon 9 Block 5 rocket earlier this month did not count as one of seven successful missions in “crew configuration” NASA says it requires before putting astronauts aboard the vehicle, officials said Thursday.

A weather satellite set to bring new storm tracking capabilities to the western United States and the Pacific Ocean rode into space atop a United Launch Alliance Atlas 5 rocket Thursday.

This is the ascent timeline to be followed by the United Launch Alliance Atlas 5 rocket in launching the Mobile User Objective System satellite No. 4 on Wednesday at 5:59 a.m. EDT.