Sellers at the orbiter BKHD after completing the task for EVA1 on STS-121 / Expedition 13 joint operations

S121-E-06097 (8 July 2006) --- Astronaut Piers J. Sellers, STS-121 mission specialist, repositions tethers at the forward bulkhead of the Space Shuttle Discovery after completing the Orbiter Boom Sensor System (OBSS) evaluations during the mission's first session of extravehicular activity (EVA).