Mercury_Notes

Mercury

The innermost planet of the solar system, hard to see with optical telescopes, with a rotation period of 59 days and orbits the Sun in 88 days.

Solar day on Mercury

Equal to two Mercury years due to its long rotation and short orbit around the Sun.

Atmosphere of Mercury

Not detectable because it is too hot, too small, and too close to the Sun.

Temperature range on Mercury

Night side temperature is around 100 K, day side temperature is around 700 K, and polar temperature is about 125 K.

Craters on Mercury

Similar to the Moon, but less deep due to low gravity; older craters may be filled with volcanic activity.

Scarps

Long cliffs on Mercury formed when the crust cooled, shrank, and split.

Caloris Basin

A large impact feature on Mercury, about 1400 km wide, with rings of mountains and indication of volcanic activity.

Magnetic field of Mercury

Very weak, about 1/100th as strong as Earth's, possibly due to slow rotation.

Core of Mercury

Probably iron-rich, contributing to the planet's weak magnetic field and geology.

Geological activity on Mercury

Geologically inactive for the last 4 billion years; past activity included volcanism, melting, bombardment, and slow cooling.

Plate tectonics on Mercury

Did not develop due to fast cooling.

Orbit of Mercury

Exhibits a daisy pattern.