Live coverage: Soyuz crew capsule departs station, lands in Kazakhstan

NASA has purchased two seats on Russian Soyuz capsules launching later this year and in early 2018 to expand the crew on the U.S. segment of the International Space Station from three to four, and reserved options to fly astronauts on Soyuz spacecraft in 2019 if commercial rides are not available in time.

NASA has agreed to consider a Boeing proposal to extend the first piloted test flight of its commercial CST-100 Starliner crew capsule from two weeks to up to six months with an extra crew member for the International Space Station, hedging against potential delays that could jeopardize U.S. crew access to the orbiting outpost.

The towering structure to be used for liftoffs of NASA’s Space Launch System rolled from a construction site to launch pad 39B at the Kennedy Space Center in Florida this week, arriving at the seaside complex Friday for a week of fit checks.