Dillon Perry made the discovery of the mystery rock while hunting for agates along the Yellowstone River near Greycliff.

Perry made the discovery of the mystery rock while hunting for agates along the Yellowstone River near Greycliff.

Diane (Susan Walters) was excited to show off the results of her hard work to her husband, Jack (Peter Bergman). Jack wasn't ...

Yellowstone's supervolcano appears to have a magma cap that vents pressure and reduces the chances of a massive eruption happening anytime soon.