Aurora is a colorful band of light that appears in the northern and southern part of the earth. Hence they are also known as northern and southern lights. They usually appear in night sky as a bright band of light. Though Auroras can be seen throughout the earth, they are more clearly visible at the poles due to prolonged darkness and magnetic field. Aurora is formed by the collision of charged high energy particles like protons and neutrons in earth’s magnetosphere with the particles in the earth’s atmosphere. This collision excites the electrons and the particles in the atmosphere. This excitation energy is released as photos into the earth’s atmosphere and hence emitting light. Gases like oxygen and nitrogen interact with the atmosphere to produce different color. Atomic oxygen results in green and red auroras. Molecular nitrogen is responsible for pink and dark green auroras while ionic nitrogen results in light blue and green auroras. Helium and neon produce purple and orange auroras respectively. Auroras are most commonly visible during the winter months. The region around the north and south poles within 2500km radius, where the auroras are clearly visible, is called the auroral zone. Auroras are also known to appear on other planets with strong magnetic fields like Jupiter and Saturn.