Mercury's surface is similar to Earth's moon: it's covered by impact craters and comets due to the lack of a strong magnetosphere. Furthermore, despite the sun appearing 3 times the size as it does on Earth, the sky would still be black, due to the lack of an atmosphere on Mercury. Most of the surface on Mercury would appear grayish-brown. Sometimes there are bright streaks of color called crater rays, which are caused by impact with massive asteroids and comets. 

Temperatures on Mercury are extreme. On the surface, temperatures can reach 800 degrees F in the morning and drop to -290 degrees F at night. This drastic change in temperatures occurs because Mercury virtually has no atmosphere to trap heat. Mercury is not only too small, but also too hot, so it does not have enough gravity to retain an atmosphere for long; but it does have a thin, surface-confined outer escape layer containing hydrogen, helium, oxygen, sulfur, calcium, potassium, and other elements. Mercury may even contain water ice in the north or south poles in areas that are in permanent shadow. The gravity on Mercury is 0.38g, which means that if you weighed 100 pounds, you would only be 38 pounds on Mercury. Mercury has no known potential for life due to its extreme temperatures and solar radiation.