A STAR may be defined as a huge, massive body of luminescent matter Radiating enormous amount of energy every second. Each star holds around itself, under the influence of force of gravity, a variable number of relatively small sized, non -radiant bodies of matter, called planets. The basic difference between a star and a planet is in their masses:a star thousands times bigger than a planet. Because of such an enormous mass very high temperatures are reached in the interior of a star that make it radiate energy. Our sun is also a typical star. It has nine planets held and revolving arount it under gravitation. The sun and the planet taken together make a solar system. Each galaxy is believed to contain billions of solar systems, our solar system the sun in the center and nine planets revolving around it is just an insignificant part of our galaxy, named by us for our convenience, as Milky Way

The nine planets revolving around the sun in order of their increasing distance from the sun have been named as mercury, venus, the earth, Mars, Jupiter, saturn, uranus, neptune and Pluto
