Solar System: The Sun

Despite its all-important role in our lives, to the rest of the universe our Sun is a very average star. Average in its size, brightness, temperature, and even age (about 4.5 billion years). Like all stars, the Sun is a huge ball of gases that creates and emits radiation, including the light and heat responsible for our existence. The Sun's light takes 8 minutes to travel the approximately 93 million miles to the Earth, but other forms of energies take as little as seconds or as long as days to make the trip.

Scientists use observatories both here on Earth and on satellites to study the energy that comes from the Sun. We can observe directly the Sun's three outer layers, but there are three more layers within the Sun that we know of only through indirect observations. By studying what happens in the visible regions of the Sun, what energy comes from the Sun, and how that energy moves through the Sun, scientists have been able to determine what goes on in those hidden layers.