On a similar thread, someone had posted a group of links from varied sources that mentioned, individually, over a half dozen planets and moons in our solar system that were heating to some degree. I wish I had clipped & saved that.
If something’s getting hotter - examine the heat source - a grade schooler can follow that logic. The sun is our system’s heat source.
It’s Bush’s fault...somehow he’s causing warming on Mars and Neptune as well!