Our sun is a hot and shiny ball of hydrogen and helium in the center of our solar system. It is 1,392,000 km in diameter, which makes it 109 times wider than Earth. The surface temperature reaches 5,500 degrees Celsius, and 15,000,000 degrees Celsius in the core.
Turns out our sun is a medium-sized star. There are bigger stars and there are smaller stars. We find stars that are 100 times larger in diameter than our sun. Truly, these stars are huge. We also saw stars only a tenth the size of our sun.
Our sun is a little unusual because it has no friends. It is just a sun surrounded by planets, asterioids, comets and dwarf planets. But solar systems can have more than one sun. In fact, this is often the case. More than half of all stars are in multiple star systems. This means that the solar system has two or more suns in it.