MERCURY

Mercury was named by the Romans after the messenger of the gods because it seemed to move more quickly than any other planet. Mercury is the innermost planet in our solar system and is the second smallest one.

Mercury is like our moon with lunar-like terrain but is more dense. Mercury has almost no atmosphere. On Mercury, due to its closeness to the Sun, the temperature rises to over 400° C (750° F) during the day. At night, because of the lack of atmosphere to help retain heat, the temperature drops to -180° C (-300°F).

Mercury Statistics

Mean distance from the Sun (km) .................. 57,910,000

Orbital period (days) ................................ 87.969

Maximum surface temperature ........................... 427°C

Minimum surface temperature .......................... -173°C

Atmospheric composition Helium .............................................. 42% Sodium .............................................. 42% Oxygen .............................................. 15% Other ................................................ 1%

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