The U.S. Space Force has become the sixth and newest branch of the nation's military, after President Trump signed the National Defense Authorization Act.
Boeing's CST-100 Starliner — a capsule designed to one day bring humans to orbit — is back on Earth after the uncrewed spacecraft failed in its bid to dock with the International Space Station.
Why it matters: The Starliner was originally expected to bring its first crew to the space station for NASA in early 2020, but this mission's problems may call that timeline into question.
/2019/12/23/1577066859588.gif?w=3840)
