The document describes the relative sizes and motions of the Earth, Moon, and Sun as seen from Mars. The Earth and Moon are spherical, and the Moon is about 1/4 the size of Earth. The Moon orbits Earth every 28 days and Earth orbits the Sun every 365 days. The Sun is about 110 times bigger than Earth and appears to move across the sky and rise in the east and set in the west, causing the cycle of night and day.