SHOULD BE NO BRAINER FOR NASA
DON'T WANT NAIL BITER LANDING
No mission to space is free from risk, but I hope NASA does not take an unnecessary gamble by choosing not to repair the damage to Endeavour's heat shield.
One of the reasons NASA grounded the Space Shuttle fleet after Columbia was lost was so it could develop ways to repair the heat shielding tiles should they become damaged during launch. It was damage to said tiles, that caused the failure of the heat shield and the loss of Columbia and its crew.
NASA said at the time it didn't know the heat shield had been damaged during launch. If it did, officials said, it wouldn't have been able to fix the problem anyway. All true, as best we can tell. Well, now the space agency has improved both of those conditions.
Endeavour sits in orbit now and new procedures helped NASA identify damage to the heat shield. Good thing they've got the tools, and knowledge to repair the problem. They may decide, however, to keep their fingers crossed on re-entry instead.
I'm not an astronaut (although I did go to space camp). I'm not an aeronautical engineer. It just doesn't sound right, though, does it? We're not going to fix it?
Every space walk presents certain risks, and apparently a space walk to repair damage is not an easy one. Officials, all of whom I'm certain are smarter than me, are trying to weigh which is the greater risk... a space walk to fix the damage, or flying home with a hole in the heat shield. They are apparently worried an attempt to fix the damage, could actually cause more problems.
In support of the "let's take our chances" argument... there should be little doubt that previous shuttle missions took hits to the heat shield, and more than 100 of them came back safely to earth. Columbia was the exception to the rule... not likely the first time ever the heat shield was damaged.
Still... if it's me in the control room, or in the shuttle, I'd say, "we're go for space walk."
You figured out how to identify the damage. You figured out how to fix the damage when identified. Do it. That's why you went through this trouble. I would not want to be in mission control "hoping" things hold together on reentry when there was a way to fix a problem I knew was there.
Like I said, these folks are smarter than me... whatever they choose my thoughts are with the astronauts and their families. Good luck Endeavour.