The planet closest to the sun has no atmosphere, oceans or visible signs of life. While mostly very hot on its day side, the poles are cold enough to support megatons of water ice.
Full Story: What Would It Be Like to Live on Mercury?
To an astronaut standing on its surface, Mercury would appear similar to the moon.
Gravity on Mercury is nearly the same as it is on Mars, about one-third the gravity on Earth, despite the fact that Mars is much larger. This means that Mercury is very dense.
Temperatures on Mercury range from minus 290 degrees Fahrenheit (minus 180 degrees Celsius) at the coldest, up to 800 degrees Fahrenheit (430 degrees Celsius) in the daytime.
Read our full special report:
Living on Other Planets: What Would It Be Like?
Have you ever wondered what it would be like to live on the moon? What about Mars, or Venus or Mercury? Find out what it might be like to live on other worlds in our solar system, from Mercury to Pluto and beyond in our 12-part series.
- Latest Photos of Mercury from NASA's Messenger Probe
- Planet Mercury: Simple Facts, Tough Quiz
- Most Enduring Mysteries of Mercury