Visions of the Cosmos
Twinkle, twinkle little star
How I wonder what you are
Up above the world so high
Lie a diamond in the sky
Unlike the writer of the well known poem we now have a very good idea of what stars are. First of all they are not little. They are immense thermonuclear furnaces rushing through space at enormous speeds. Although the stars are huge beyond our comprehension, the space they move in is even greater by many orders of magnitude otherwise they would frequently be colliding. It is the very vastness of interstellar space that has allowed planets to form and for life to evolve on Earth. and many believe on other worlds. By the beginning of the seventeenth century it became obvious to far sighted people that the our Sun was a star and that most of the tiny points of light that blazed in the night sky were like our sun but very far away from us. One man Giordano Bruno was burnt at the stake on 17 February 1600 for heresy. One of his heresies was to dare to suggest that the stars were in fact other suns. Soon as the enlightenment illuminated the minds of thinkers all over Europe it became taken for granted that our Sun was only one of many stars. Great minds like Christiaan Huygens were even going so far as to suggest that life existed on planets orbiting other suns.
The next great advance in thinking occurred in the nineteenth century when scientists like Fraunhofer, Kirkchoff, Bunsen and Ångström proved beyond doubt that the same chemical elements which occurred on Earth were also present in the Sun and in other stars. They and many others developed the wonderful new science of SPECTROSCOPY. Without this almost no progress in astronomy would have been possible.
The next series of discoveries in the twentieth century answered the greatest mystery of all - what caused the Sun and other stars to shine. It was the discovery of atomic physics and thermonuclear fusion that led scientists to explain how stars 'burnt' and radiated huge amounts of energy into space and why they were able to shine for thousands of millions of years.
This is the third section of the web-site and like the section on the Solar System forms a semi-self contained unit - a sort of sub web-site. It is the first introductory page on stars and can be accessed from the 'Home' Page, from the Solar System page and from the other main pages in this section. The pages on the stars will be as follows:-
Our Star the Sun
The structure and composition of the Sun
Thermonuclear Reactions in the Sun
The Solar Wind
The Sun as 'Emperor' of the Solar System
The Heliopause and the limits of the Solar System
Types of stars
Gas Giant Planets as 'Failed Stars'
Brown Dwarfs as intermediate in size to 'True Stars'
Red Dwarf Stars
Sun-like Stars - K and G Spectral Types
Massive and Super-massive Stars. The production of chemical elements above helium and up to iron
The Lives of Stars
Main Sequence Phase
Planetary Nebula and White Dwarf Phase
Supernova - Neutron Stars and Black-holes. The production of elements up to iron and beyond iron in the periodic table
The BIG BANG the production of matter. This will be dealt with more deeply in the fourth section on particle physics.
The 'Dark Ages'
The 'First Stars'
Galaxy Formation and Evolution
Dark Matter and Dark Energy
Speculations - Universe Formation - the Multiverse and Parallel Universes - Possible Ends
External Hyperlinks (3)
next Section Our Star the Sun
The Solar System
Our Star the Sun
The Solar Wind
Types of Stars
Superstars and Supernovae
The Magic Furnace