Cosmic Reference Guide
Sun
| Surface Temperature: |
5500�C |
| Internal Temperature: |
15,000,000�C |
| Distance From Earth: |
150 Million KM (1 AU) |
| Light Travel Time From Earth: |
8mins |
The Sun is made up of super hot gases, 70% Hydrogen, 28% Helium, the remaining gases are trace amounts of the elements that form the Earth and all other planets in our system.
The most seen face of the Sun, the `photosphere` is the bright red disk that is seen if you look at the sun while it is rising or setting, however, during an eclipse the true surface can be seen. This is the `chromosphere`, or `corona`, it is a zone of hot gas, many thousands of kilometres deep that appears round the edge of the Sun while it is covered. This ring appears irregular due to the fact that it is distorted by solar flares and violent eruptions.
Also visible on the surface of the Sun, are sunspots, which are Earth size rips in the Sun's surface that are as much as 2000� cooler than the surrounding area, these sunspots and the other erruptions on the Sun, are in a 11 year cycle of activity, but it is not know why.
The energy required by the Sun to consistantly give out the light and heat required for life on Earth is produced by a process called `thermonuclear fusion`. The Hydrogen nuclei fuse together at tremendously high temperatures, and with each fusion some of the mass of the nuclei is released as energy, and only a tiny amount is needed to produce enormous amounts of energy. This process will continue until all the Hydrogen is used, in approximately 5 billion years, the Sun will then begin the process of turning into a White Dwarf Star, (unfortunately destroying Earth in the process).
As well as visible light and heat, the Sun also puts out large amounts of radiation, most of which, thankfully, is stopped by the Earth's Ozone Layer.On August 11 1999, there will be a total eclipse of the Sun, viewable from south western Europe. I will (hopefully) be including pictures of this on a special page.