The solar eclipse is a multiple step process and is extremley difficult (Best done in a dark room).
1. Stretch your ball skin so it resembles the move the batwing
2. You put a flashlight behind the stretched skin. If done correctly there should be a white circle, the "sun".
3. Then take your other hand and slowly push one of your testicals across the circle of light.
4. Admire your great feat.
The difficulty is holding the skin tight while holding the flashlight in place while pushing the balla across.
Guy #1: Dude last night Nick pulled the Solar Eclipse on me when I went into my room.
Guy #2: Oh shit, Nick has skills. That move is fucking hard to pull off.