HIS SKELETON, survived it, And jean grey reanimated him from his admantium, Damnit, didnt you read the "All knowing" Never's post... *cough* sarcasim *cough*
As for the extent of superman's power...
DC CHARACTER BUILDING STUDIO.
2:30 AM.
"Dude... We have to make this new hero by 8 or were gonna get axed..." Some guy.
"I know I KNOW but making a hero is hard!" Some guy 2
"Yea, well, were gonna have to think, or were fired... How about a fast runner?" Some guy 3.
"No, theres the flash" Some guy 2
"Yup" some guy 1
"Dangit..." Some guy 3
"Well..."
"Since were gonna get fired... lets PULL OUT DA BEER!" Some guy 1
After drinking, LOTS, 5:30 am.
"OK OK OK... U MAKE DUHHHH COSTUME..." Some guy 1
"Yup! We make him... dis... He get super strong! And... We give him all this crap... Laser eyes... And see through eyes... Make him so cheap ass that... Even hulk cant beat him!" Some guy 3
"Thats marvel! Bizzzzaaaaatttchhh!" Some guy 2
"Sooooo?" Some guy 3
My point being, Is, Superman was just some hero, that was thought up in like 5 minutes by a group of stupid japanese drunks. "Lets make flashy lights, and bright colors that give people seuizures come out of his eyes!"
Hes the cheapest hero in the books, and they thought him up in like 10 minutes before a board meeting. So, I wouldnt be surprises if he could walk in the sun and have sex with the burning hot gas itself.