What is a solar system? -composes the Sun together with the eight planets and their moons -includes other celestial bodies that orbit the sun the largest object in our solar system -where most of the ENERGY and LIGHT on Earth comes from. known as the twin planet of the Earth also called as “Morning Star” or “Evening Star” It has a thick, poisonous atmosphere of carbon dioxide and sulfuric acid. Venus spins backwards compared to other planets Earth is a water world, with two-thirds of the planet covered by ocean. The only world known to harbor life. Oceans at least 4 km deep cover nearly 70 percent of Earth's surface. Known as the RED PLANET Mars is a small rocky body once thought to be very Earth-like. Volcanism, impacts from other bodies, movements of its crust, and atmospheric effects such as dust storms have changed its surface. It has polar ice caps that grow and recede with the change of seasons. planets