A Tough Day in Orbit

The report from today's work on the International Space Station (ISS) reminds us how challenging major construction in space can be. Spacewalkers from the 7-person crew of the STS-120 mission had to move a pair of stored solar wings to their final position at the opposite side of the station and install them. At some point in the procedure, a 75-cm tear appeared in the wing. The power loss is minimal, but there's some concern about the structural integrity of the wing. The ISS does not just float up there: every section is under a variety of stresses as the complex structure zips through space at orbital velocity. NASA had lengthened the mission a day to allow for possible repairs to the wing as well as inspection of a joint found to be contaminated with metal shavings.