The Terrestrial Planets Mercury Stats Diameter 0 38

The Terrestrial Planets

Mercury Stats Diameter 0. 38 DE Rotation Period 59 days Orbital Period 88 days Distance from Sun 0. 387 AU Orbit Eccentricity/Tilt 0. 20 / 0 degrees Temperature -183 C to +430 C Atmosphere none Gravity 0. 376 g Moons none Visits 1 Mariner 10

Mercury's Interior Exceptionally large Iron core for its size => Weak Magnetic Field Gravity too low and temperature to great to sustain an atmosphere Rotates three times in exactly two solar orbits – 3: 2 Spin-Orbit Resonance

Mariner 10 Reached Mercury 29 th March 1974

Mercury Mosaic To this day there has only been one mission to Mercury

Venus Stats Diameter 0. 95 DE Rotation Period 243 days Orbital Period 228 days Distance from Sun 0. 723 AU Orbit Eccentricity/Tilt 0. 01 / 178 degrees Temperature +470 C Atmosphere CO 2 Gravity 0. 903 g Moons none Visits >20 Mariner 2, Venera 7 9 & 10, Magellan

Venus is in a 3: 2 tidal resonance with it's “sister” planet the Earth. 178 degree tilt means it's rotating backwards – i. e. retrograde. No magnetic field. Thick carbon dioxide atmosphere with sulphuric acid clouds moving at high speed. Atmospheric pressure is 90 x that of Earth. The greenhouse effect makes Venus the hottest planet in the solar system.

27 th August 1962, Mariner 2 – the first interplanetary craft flies to Venus

Mariner 10 – Fly-by image of Venus' Clouds Venus as viewed by an amateur on Earth

Venus from Galileo (True Colour!)

Venera 9 and Venera 10 images The first images from the surface of another planet

Image by Magellan and Arecibo