Mercury, the Extreme Little Planet

시즌 1, 에피소드 2: Mercury is a planet of many solar system extremes. It's the smallest planet, the closest to the Sun, and it has the shortest year, most elliptical orbit, smallest axis tilt, and largest fraction of iron. Learn how these characteristics have resulted in a planet where the Sun sometimes moves backwards across the sky, and where water ice has been found at the poles.