The document summarizes key facts about the four inner planets of our solar system: Mercury, Venus, Earth, and Mars. It provides details on each planet's diameter, mass, density, atmosphere, distance from the sun, orbital path, moons, surface features, and core composition. Notably, it describes Mercury as the closest planet to the sun with no moons and a heavily cratered surface. Venus is similar in size to Earth but has a dense carbon dioxide atmosphere and retrograde rotation. Earth is unique in its liquid water and life. Mars has the largest volcano in the solar system called Olympus Mons and two small moons.

1. The Inner Planets Mercury, Venus, Earth, and Mars

5. Caloris Basin

8. Surface Retrograde Motion

11. “ Moonrise” Antarctica Earth From Space Satellite Image of Earth

14. Olympus Mons Mars with Moons, Phobos and Deimos Surface

15. Inner Planet Orbit

16. Earth Compared to Inner Planets Earth and Venus Earth and Mercury Earth and Mars