The Solar System and Beyond

Prime objective of this lecture is to present on the Solar System and Beyond. The Earth gets heat and light from the Sun. The Earth spins on its axis. It orbits around the Sun. Our sun is one of at least 100 billion stars in the Milky Way, a spiral galaxy about 100,000 light years across. The stars are arranged in a pinwheel pattern with four major arms, and we live about two-thirds of the way up one of them. Most of stars host their own planets. The Milky Way is part of the Local Group, a neighborhood about 10 million light years across, consisting of more than 30 galaxies that are gravitationally bound to each other.