Wow... OK where to start...
First off, why are you applying real world to physics to comic/mangas? And you seem to make the assumption that superman only has power when the sun is shining. Then go on to say he can't even have the the full power of a yellow star, since thats where he gets his power from.
You fail to mention (or maybe you don't know) Superman doesn't just 'get' energy from the sun he absorbs the radiation(like a battery)... This is why he still has powers even at night.
You can go on to say 'Well he couldn't had adsorbed THAT much radiation!'.
The fact is, it doesn't have to make sense in our world. mail the writers, I'm not going to go back and read all the Superman comics to find proof of what he's done, however all the examples I used is what he HAS DONE.
And what he HAS DONE overcomes ANYTHING Goku or frankly any other
manga character(aside gurren laggen) has ever done..
Superman>Goku
PS:
I was never implying Wildcat/Batman (well maybe Batman) where martial artist on the level of Roshi, I was just saying Obviously Superman isn't just going to be throwing haymakers, Even if all his training from Batman went to waste he knows all the Kryptonian Martial Arts.
And here's something I just found about his speed.. like I said real world physics matter little. The fact is he's done it. Don't act like its not fair and DBZ has never broken the laws of physics either.. that would be a joke.
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