And Oxygen

International Space Station Astronauts are breathing easier now that their supply ship has arrived. The ISS Progress 18 spacecraft docked at 2042 EDT to the aft port of the Station's Zvezda Service Module.

Progress 18 lifted off Thursday at 1910 EDT from the Baikonur Cosmodrome in Kazakhstan. It reached orbit in less than 10 minutes, and moments later, automatic commands successfully deployed its solar arrays and navigational antennas.

The docking was controlled by Station Commander Sergei Kirkalev using the Telerobotically Operated Rendezvous Unit (TORU). The automated Kurs docking system was not used because a problem with a Russian ground station prevented uplinking a command for Progress to begin the final approach. Krikalev was helped by NASA Science Officer John Phillips in the manual docking operation, which went flawlessly. (Photo from Progress approaching ISS)

The ISS Progress 17 cargo ship, which had been at the Station since March 2nd, was undocked on Wednesday, clearing the aft port of Zvezda for the new Progress. Filled with trash and discarded items, Progress 17 was commanded to deorbit by Russian flight controllers. It re-entered the atmosphere and was incinerated about four hours after undocking.

The cargo includes food, fuel, air, oxygen, 40 solid fuel oxygen generation (SFOG) cartridges and parts for the Elektron oxygen generation system. The air, oxygen and SFOGs will add to the existing supplies of oxygen aboard the Station. Flight control teams in Houston and Moscow hope the new parts will enable the crew to reactivate the Elektron, which has been out of service for several weeks. A new liquids unit that circulates water to be broken down into oxygen and hydrogen is to be launched later this year.

Crewmembers plan to open the Progress hatches Saturday, but won't begin unloading the cargo until Sunday. Beginning Monday, they plan to use oxygen from the Progress to replenish the Station's atmosphere instead of using the SFOGs.

FMI: www.nasa.gov/station