The Sun
Because we are so close to the sun, it is the only star that we can examine in detail. With a diameter of 1,392,000 km (865,000 miles), it could engulf over 1,000,000 Earths! At the core where the energy is being produced, the temperature could be as high as 15,000,000 degrees centigrade; even the surface that we can see (the photosphere) is at 5500 degrees centigrade. It is here that you can see sunspots and bright regions known as faculae. Above the photosphere comes the chromosphere, and finally the sun's outer atmosphere - the corona.
The Sun is near to the edge of our galaxy - the milky-way. It is 25,000 light-years from the centre. The sun is moving at 140 miles per second, as it shares the rotational movement of our galaxy. It takes the sun 225 million years to complete one circuit.
