Wow, that's 45 degrees

(which is a lot hotter than mine I think.)
I'm in the same camp as "SDDave2007" though. This is not necessarily indicative of much at all.
Three things to think about:
1) You don't give any actual information that would allow anyone to access the situation and answer your question. Like what kind of Time Machine it is, how many machines it backs up, where you have it seated, what the "normal" room temperature is as a comparison, what kind of probe you used, and about a dozen other factors that might be affecting it.
2) If you search the forums you will find *hundreds* of posts about how Apple computers and devices can get really warm at times (especially the ones without any fans inside). The standard answer is that if the computer doesn't melt, burn your hand, catch fire, or fail
because of said heat, then how hot it gets is actually completely
irrelevant.
3) How hot is
"super hot"?