Two Robot Arms to Move Huge Solar Arrays Today

When you lift something heavy, sometimes it takes the use of both arms to place it where you need it. And for the crews aboard the Discovery/ Space Station complex, this will hold true today as well.

Late this morning (11:18 am EDT), astronauts using Discovery's 50-foot robotic arm will slowly lift the huge Starboard 6 (S6) Truss segment from the center of the shuttle's payload bay. [image above at 8:48 am today] Three hours later, the station's shorter robotic arm will move it into a specific attitude relative to where the S6 will need to be placed. Then four hours after the first transfer between arms (6 pm EDT), Discovery's arm will regrapple the S6 and hold it near where it will be attached to the right side of the station until tomorrow.

The S6 is a huge complement of four long solar array panels which will be attached to the right side of the space station, and increase the electrical power being generated to help bring more experiments and computers online. As the station's size has increased, so has the number of international partners who have participated in the construction of this beautiful orbital outpost in space. The entire truss weighs 31,100 pounds here on earth.

The Starboard 6 truss supports two 115 foot solar array wings on either side of a mast giving the total length of arrays to 240 feet from end to end. And, according to Mission Control at the Johnson Space Center, "the four sets of arrays can generate 84 to 120 kilowatts of electricity – enough to provide power for more than 40 average homes".

Tomorrow, two astronauts will perform the first of three planned spacewalks to assist in the mounting of the S6 to the station and attaching cables between the Starboard 6 truss and the station.

At 8:43 am EDT, the crew of Discovery were awoken to the tune of Johnny Cash's I Walk the Line, to begin their flight day 4 activities.