Live coverage: Cygnus supply ship readied for station departure

Eight days after a dramatic spacewalk to inspect the site of a leak in the hull of his Soyuz ferry ship, Russian commander Sergey Prokopyev, German flight engineer Alexander Gerst and NASA astronaut Serena Auñón-Chancellor geared up to depart the International Space Station Wednesday for a fiery plunge back to Earth.

United Launch Alliance called off the planned liftoff of a Delta 4-Heavy rocket and a classified National Reconnaissance Office spy satellite from Vandenberg Air Force Base in California on Wednesday after indications of elevated hydrogen concentrations around one of the launcher’s main engines. Three previous launch attempts were scrubbed by technical concerns and bad weather.

Engineers have started testing a new way to use the Curiosity rover’s drill to bore into Martian rocks after a motor in the device stalled late last year, but ground teams are still months away from the first chance to resume drilling operations.