Aboard the shuttle are Commander Mark Kelly, Ham and Mission Specialists Karen Nyberg, Ron Garan, Mike Fossum, Greg Chamitoff and Akihiko Hoshide, a Japan Aerospace Exploration Agency astronaut.
Today’s activities will focus on performing an inspection of the shuttle’s thermal protection system. This will be a limited inspection using the end effector camera of the shuttle’s robotic arm. This inspection usually would be completed using the Orbiter Boom Sensor System (OBSS), the special attachment on the end of the shuttle’s robotic arm, but due to the size of the Kibo laboratory, Discovery could not carry its own OBSS. During the last shuttle mission, STS-123, Endeavour left behind its OBSS at the station after it had performed its inspection. Discovery will retrieve that OBSS and use it to perform a more detailed inspection on the seventh flight day of the mission. Discovery will then bring the OBSS back home with it when it returns to Earth.
The shuttle crew also will spend the day checking out the equipment that will be used during the spacewalks that are scheduled for the STS-124 mission. They will install the centerline camera, which is used as the shuttle approaches and docks with the station. The crew also will extend the orbiter’s docking system ring and conduct a survey of the shuttle’s orbital maneuvering system (OMS) pods.
During Discovery’s launch, there was a loss of electronics on a secondary gimbal actuator on the shuttle’s left OMS pod. That OMS engine is still usable and has been put into a parked position, and there is no impact to the mission. The shuttle conducted a series of OMS burns after it reached orbit to fine-tune its approach to the station, and the orbiter performed nominally. Flight controllers will continue to examine the issue to determine if it is a mechanical or instrumentation issue.