Astronauts will have to make in-orbit repairs on the heat shield of Atlantis. During Atlantis’ liftoff a corner of the heat-protection blanket peeled off exposing a 4-by-6 inch wedge of an engine casing to the left of the ship’s tail.
The heat-protection shield protects the shuttle from super-heated gases that cover the spacecraft during its re-entry phase. A similar damage had occurred on Space Shuttle Columbia that later caused the death of all the seven astronauts aboard it.
Since the Columbia disaster, NASA has remained cautious of the blanked and they have developed an emergency heat-shield repair kit that now will be used to repair the shuttle.
The repair will be made during a spacewalk already scheduled for Friday, or an unplanned forth spacewalk will be conducted to repair the damage.
During re-entry the engine casing heats up to 700 to 1,000 degrees, causing the graphite-epoxy material that makes up the wall of the engine casing starts to burn away at 250 degrees. Any damage to the heat-shield means that the engine will be exposed to super-heated gases and its parts can melt away, the results of which can be disastrous.
The Atlantis crew will also have to bolt an addition onto the space station. Astronauts James Reilly and John “Danny” Olivas plan to exit the space station at 3 p.m. ET for a spacewalk to attach a new girder with a giant solar panel attached. This solar panel will provide the station with the extra power needed to run the equipment that will be added to the space station in the coming years.
Via: usatoday
