Mercury has the shortest and fastest orbit around the Sun and experiences dramatic temperature changes as it rotates. It is a world of extremes. Explore facts about our solar system's fastest planet.

the inner planet Mercury is only rarely visible to Earth observers: only near times of greatest elongation, and when other conditions - such as when the tilt of the ecliptic (the apparent path of the ...

“To get seasons, a planet needs to have ... where you are in the world. Mercury’s seasons are difficult to determine. This is because it has virtually no tilt (0.03 degrees), but a highly ...