Live In Orbit: Astronauts Tackle Unfinished Business

Spacewalking astronauts are trying to tackle some unfinished business after successfully positioning a rail cart for future International Space Station assembly and maintenance work.

Anchored to the end of the station's 57-foot Canadian-built construction crane, former Melbourne High School science teacher Joe Acaba carried the rail cart from the port side of the station's central truss to a work site on the starboard side of the outpost's skeletal backbone.

Spacewalking partner Ricky Arnold served as an extra set of eyeballs, giving Acaba verbal directions that helped him secure the rail cart at work site No. 4 on the starboard side, which is located atop the innermost -- S1 -- segment of the starboard end of the truss. The rail cart had been located on the P1 segment on the port side of the truss.

You can click to enlarge the NASA screen grab above. It shows Acaba on the end of the station's robot arm with the rail cart in hand. Discovery mission specialist John Phillips served as the robot arm operator inside the joined shuttle-station complex.

You can also click to enlarge the NASA screen grab, which shows Acaba preparing to set up a portable foot restraint on the end of the Space Station Remote Manipulator System, affectionately known as "The Big Arm."

Much of the work is being done as the shuttle-station complex is on the dark side of the Earth. So the astronauts have been employing helmet lights to see what they are doing.

You can click to enlarge the NASA screen grab below, which shows Arnold's helmet lights illuminating an area on the port side of the station's truss. The view comes from Acaba's helmet-cam.

The astronauts now are back on the port side of the truss, where they are trying to set up an experiment platform that Acaba and crewmate Steve Swanson failed to deploy during a spacewalk on Saturday. A latching pin was installed backward and it prevented the full deployment of the Unpressurized Cargo Carrier Attachment System platform.

The astronauts are trying to use extra force to get the platform to deploy, but so far, they've had "no joy."

You can watch the action unfold here in The Flame Trench. Simply click the NASA TV box on the righthand side of the page to launch our NASA TV viewer and live coverage. Be sure to fresh this page, too, for periodic updates.