Live coverage: Vega rocket launches with LISA Pathfinder

An Ariane 5 countdown in French Guiana was aborted Tuesday with the European-made rocket’s main engine already running, postponing the launch of two commercial communications satellites until engineers can resolve the problem.

Russian commander Sergey Ryzhikov, flight engineer Sergey Kud-Sverchkov, and NASA astronaut Kate Rubins climbed into their Soyuz landing craft and undocked from the International Space Station at 9:34 p.m. EDT Friday (0134 GMT Saturday). The trio touched down on the barren steppes of Kazakhstan at 12:56 a.m. EDT (0456 GMT) to wrap up six months in orbit.

Seven astronauts and cosmonauts are gearing up for launches April 9 and April 22 to the International Space Station, replacing seven outgoing crew members set to land in Kazakhstan and off the coast of Florida on April 17 and April 28.