No up-close-and-personal tours will take place at Kennedy Space Center's launch pad 39A next week after NASA finishes pressurizing helium and nitrogen tanks aboard the 22-year-old spaceship, which is scheduled to launch at 7:38 p.m. Friday.

The precaution is being taken to reduce the risk created by aging pressure vessels in the orbiter that could burst, triggering a rocket fuel fire or explosion that might injure or kill workers and seriously damage the launch pad.

It never ends...