On Thursday, flight controllers conducted a Debris Avoidance Maneuver to steer the International Space Station clear of orbital debris. Aboard the orbiting complex, the Expedition 39 crew prepared for the departure of a cargo craft Thursday and tackled a variety of experiments, including the checkout of device that incorporates electrical impulses to keep muscles fit in the absence of gravity.
Playing it conservatively, flight controllers conducted a Pre-Determined Debris Avoidance Maneuver (PDAM) Thursday to raise the altitude of the International Space Station by a half-mile and provide an extra margin of clearance from the orbital path of a spent payload deployment mechanism from an old European Ariane 5 rocket.
NASA and Russian flight controllers tracked the Sylda Adapter for the past few days before jointly deciding to perform the maneuver, which used the ISS Progress 53 thrusters at the aft end of the Zvezda Service Module for a 3 minute, 40 second firing at 4:42 p.m. EDT that provided a reboost for the orbital laboratory.
The Ariane 5 payload deployment mechanism was forecast to pass less than 2/10 of a mile of the station at 7:02 p.m. EDT had no action been taken. The six-man Expedition 39 crew was informed of the maneuver, was never in any danger and did not have to take shelter in their respective Soyuz return vehicles. The maneuver will have no impact on the upcoming launch of a new Russian Progress resupply vehicle on April 9 from the Baikonur Cosmodrome in Kazakhstan to bring almost three tons of supplies to the outpost, or the pending launch of the SpaceX/Dragon commercial launch vehicle later this month from the Cape Canaveral Air Force Station, Fla. to the station.