Video: Soyuz capsule docks to the International Space Station

Two Russian cosmonauts stepped outside the International Space Station Wednesday, sent birthday greetings to former cosmonaut Alexey Leonov, the first man to walk in space, and then carried out a full slate of maintenance work.

The capture came after Northrop Grumman engineers adjusted the sensitivity of main engine fault detection software that prematurely triggered shut downs during two rendezvous thruster firings Tuesday.

Hauling nearly three tons of supplies, hardware and experiments, a SpaceX Falcon 9 rocket shot into orbit Monday from Cape Canaveral, with a previously-flown Dragon cargo carrier riding a reused first stage booster to kick off a nearly two-day journey to the International Space Station.