Space Forum / Shuttle / December 2007

http://www.nasa.gov/mission_pages/shuttle/main/index.html

I dont think we ever get to see the back of the RSS with the Shuttle also on
the pad...cool pic I think.
anyway, refering to that "walkway type structure that leads up to the ET,
does this lead to a service port to access inside the ET? So is there some
kind of internal ladder system  inside the ET. Arent there two tanks inside,
LO2 and LH2.  I would think there wouldnt be much roon to get around inside?
Or possibly is this
where the tanks are filled? I guess gangway structure retracts inwarde
before launch

Is that covered up during the launch, Ive seen some launches where there is
visable a large black square opening on the ET during the roll program? I am
sure this has probably been discussed before, but if it isnt covered , why
isnt it?

John