|Equatorial Radius||2,439.0 km|
|Mean Density||5.43 g/cm³|
|Sidereal Rotation||58.646 days|
|Sidereal Period||87.96 days|
Sidereal Rotation=One full rotation(1 Earth day) / Sidereal Period=One revolution around the Sun
Mercury is the closest planet to the Sun which makes it difficult to find. As with the Sun, DO NOT TRY TO LOCATE MERCURY WHEN THE SUN IS UP, SEVERE EYE DAMAGE OR BLINDNESS COULD OCCUR. The temperatures on Mercury can range from a high of 430°C to -170°C. Mercury has no natural satellite. Mercury is inside the Earth's orbit, so we are always looking in at it, toward the Sun. It always rises and sets about two hours before the Sun which makes it very difficult to see. Since it's so low on the horizon, the light from the planet has to pass through a lot of atmosphere thus making for a fuzzy or "swimming" image. The rotation period of Mercury is 58.6 days and it takes 88 days for one Solar revolution.