The Sun in the centre of our solar system is a star. There are around 400 billion stars in our galaxy, the Milky Way.
The Sun is a vast globe of glowing gas that powers energy into Space as light and heat. The Sun is made up of 73% hydrogen, 25% helium and traces of around 60 other elements. Hydrogen is the fuel in the nuclear reactions that produce the Sun’s energy. The surface of the Sun heaves and boils as pockets of hot gas well up and sink back down. This gives the surface a grainy look which is known as “granulation.” At the core of the Sun the temperatures reach 15 million degrees centigrade. The Sun’s gravity keeps the planets, dwarf planets, comets and asteroids in orbit around it. The gravity is so powerful that some objects are in orbit thousands of billions of kilometres out from the Sun!
The rock planets orbiting the Sun are; Mercury, Venus, Earth and Mars.
The gas planets orbiting the Sun are; Jupiter, Saturn, Uranus and Neptune.
Some dwarf planets are; Pluto, Ceres, Make-make, Eris and Haumea.