HOUSTON — NASA’s Mission Management Team approved a second one-day extension of shuttle Discovery’s trouble-free final mission on March 3, while astronauts aboard the International Space Station (ISS) upgraded and repaired U.S. and Russian carbon dioxide removal systems and supervised an altitude-raising maneuver that sets up the departures and arrivals of future Soyuz and shuttle crews.
Discovery, which has been parked at the station since Feb. 26, now will depart the orbiting science laboratory on March 7 at 7:30 a.m. EST and head back to Earth on March 9, touching down at NASA’s Kennedy Space Center at 11:58 a.m. EST to end a 13-day flight.
The latest extension was based on Discovery’s performance and positive fuel-cell power margins. The six shuttle astronauts will use the additional day to assist with un-stowing and activating the Permanent Logistics Module they transferred from Discovery’s payload bay to the station on March 1. The 21-ft. module can house science experiments and function as a storage compartment.
“That’s great news,” Discovery commander Steve Lindsey responded when informed of the latest extension by flight controllers. “We are all excited.”
Station skipper Scott Kelly echoed the sentiments. The first one-day mission extension was granted Feb. 28.
Meanwhile, astronauts in the station’s U.S. segment installed an upgraded dessicant/sorbent bed delivered by Discovery in the newest Carbon Dioxide Removal Assembly (CDRA) positioned in the Tranquility node. It backs up an older CDRA in the U.S. Destiny Laboratory for the cleansing of breathing air. Also, cosmonauts in the Russian segment finished an overhaul started earlier in the week of the vintage Vozdukh carbon dioxide removal system.
Early on March 3, Discovery’s vernier thrusters fired for 26 min., gently raising the station’s altitude by nearly a mile into a 224 x 214-mi. ellipse. The boost sets up the March 19 departure and descent to Earth of Soyuz 24 with station crew members Kelly, Alexander Kaleri and Oleg Skripochka. The maneuver also positions the station for the March 30 launch and April 1 docking of Soyuz 26 with Andrey Borisenko, Alexander Samokutyaev and Ron Garan, as well as the April 19 launch and April 21 docking of shuttle Endeavour on the STS-134 mission carrying the Alpha Magnetic Spectrometer
The two crews also received several hours of off-duty time, much of it spent gathered in the U.S. segment cupola viewing port.
“That huge window gives us a view like we have just never had before,” Discovery astronaut Mike Barratt says. “When you are looking out and see the curvature of the Earth and the magnificent blue planet just hanging there in the blackness of space, it really does kind of take your breath away.”