All around our solar system, volcanoes are powerful shapers of worlds. Next door on Mars is Olympus Mons, a giant volcanic mountain more than twice the size of Mt. Everest. And closer to the Sun, thousands of volcanoes produce the toxic atmosphere that keeps Venus boiling. Then there's Jupiter's moon Io, the most volcanically active world in the entire solar system, and Saturn's moon Enceladus, where clues in its watery eruptions hint at the possibility of life. Discover the explosive forces that molded each of these worlds – and what makes the volcanoes right here on Earth so special.