The sun is a yellow dwarf star which is very massive, hot and ancient. It is an area of great nuclear activity and it produces multiple types of radiation. By learning about different aspects of the Earth's primary source of both light and heat, we can get a better idea of what type of star the sun is within our solar system.

The sun is characterized as a yellow dwarf star and is medium in size compared to other stars. It is one of many stars which shine throughout the galaxy known as the Milky Way. The dwarf sun burns very hot and its central temperature has been estimated to be more than fifteen million degrees Celsius.

Nuclear activity takes place within the sun. At its core, nuclear fusion transforms hyrdrogen. The result is helium. This nuclear activity sends its radiation all the way to the surface of the sun and then travels further into space. The radiations produced are both light and heat.

Light and heat are well-known forms of solar radiation on which we depend on the planet Earth but they are not the only forms of radiation which emanate from the sun. There are quite a few others including radio waves, X-rays and ultra-violet rays. The atmosphere of the planet shields life on Earth from any damaging effects which might otherwise be caused by these forms of radiation.

The sun is a massive star. It measures 1,392,000 kilometers in diameter. It is estimated to be more than four and a half billion years old and is the closest star to us. Its great mass gives it gravitational power on all the planets in the solar system and this is the reason Earth stays in orbit around the sun.