*Analysis of the "red shift" of distant galaxies. The colours of light are different "frequencies". Think of sound frequencies - when a car comes toward you, it has a higher frequency sound, and when it speeds away, it has a lower frequency sound. Light works the same way. Other galaxies all seem to have a low colour 'frequency', like a car speeding away from us. "Red" is a low frequency colour, so we call this effect the "Red Shift." The presence of this red shift tells us that galaxies are all speeding away from us. This is only consistent with an expanding universe. And if the universe is expanding, then at one point it was all closer together. The closest together that it could ever have been is a "singularity". It's expansion away from this state is known as "The Big Bang".

*The microwave background radiation. Everywhere we look in space, we see a faint haze of microwave radiation. The best explanation for this is a "big bang" at some point in the past - the big bang being the source of huge amounts of energy whose traces remain as the background radiation of the universe.

*Einstein's General Theory of Relativity. A physical theory that describes gravity better than any ever conceived of, by picturing gravity as if it were the distortion of space and time. It has held up to experiment for almost a hundred years. It predicts that the universe is expanding (as the red shift proves), which logically follows that at some point in the past, the universe was packed into a singular point (a "singularity"), and that it expanded outward from there (as the cosmic background microwave radiation shows) - this is "The Big Bang".

The Formation of Stars, the Chemical Elements, and the Earth:

The Big Bang Theory starts the universe off with a lot of hydrogen, the simplest of the elements, but nothing else. But hydrogen atoms can be crushed together to form heavier elelments, in a process called "nuclear fusion". Nuclear fusion produces an enormous amount of energy, as the US government can tell you: it is the process at work in a fusion bomb.

If you have a lot of empty space, and a lot of hydrogen in it, you have big hydrogen gas clouds. If you have big hydrogen gas clouds, they're going to start collapsing, as each part of the cloud is attracted to the others by gravity. When enough hydrogen collects together, it will settle into a spherical shape. The force of gravity, pressing all that hydrogen together, is enough to start actually fusing the hydrogen atoms together - Nuclear fusion. When nuclear fusion occurs, it releases lots and lots of heat and light. Fusion also transforms hydrogen into heavier elements (a hyrdogen atom plus another hydrogen atom results in an atom that is twice as heavy as a single hydrogen atom - a helium atom). So you have a big, hot, bright, ball of hydrogen that's processing it's hydrogen into heavier elements: a star.

*Analysis of starlight. Different elements give off different kinds of light when they burn. Step into any chemistry lab in the world, and they'll tell you this. When hydrogen burns, it gives off a certain kind of light. When we look at starlight, we can tell what the star is made of - using the light to calculate which elements are burning in the heat from the nuclear fusion.

As nuclear fusion progresses, heavier elements should naturally start appearing (as the hydrogen atoms are fused into these atoms of larger elements, and then these, in turn, are fused into even larger ones). And the analysis of starlight shows us that many stars contain heavier elements, as well as the hydrogen.

Now, nuclear fusion releases energy as light and heat that will push the star outwards. But the star is held together by gravity, trying to pull everything inwards. When the fusion starts to slow down (because there is less hydrogen to fuse with - and the heavier elements that are produced will not fuse quite as easily as hydrogen did), the star starts to shrink.

Eventually, the star runs out of these, so it collapses and more fusion happens, making more elements. Eventually, all the elements known to science are created. Fusion slows down again as they're used up, and the star collapses in size again, and, if the star is big enough, this next gravitational collapse is powerful enough that the last wave of fusion occurs, and this last wave of fusion occurs so suddenly and on such a large scale that it blows the outer layers of the star to pieces.

The remains of the outer layers of the star are scattered through space, as huge expanding clouds of elements.

*Observations of nebulosities in space (such as the Crab Nebula), and of "supernova" occuring. Direct evidence that this happens.

This is where the elements that make up the solar system would have come from. Of course, wether or not the star goes this far depends on how big it is, which depends on how much hydrogen originally collapsed to form it.

So some stars with different initial masses of hydrogen to the exploding stars (like our sun, for example) have slightly different lives. And all these different lives can be described by physics. All the stars we see in the sky - a wide variety, from tiny "red dwarves" to huge "white supergiants" - represent stars that started with different masses and thus have different lives, or who are at different stages in their life cycle.

With all these elements scattered through space by stars undergoing these massive explosions, some of the new stars would start to have discs of dust and gas collect around them. We can see some of these out there.

*Beta Pictoris and Epsilon Eridani. And our own solar system. - stars with orbiting discs of matter.

There's a lot of stuff floating around the solar system, kept there by the sun's gravity. This stuff would collect, over time, to form bigger chunks of stuff. If the chunks are big enough, gravity would collect them into spheres such as the Earth. So now we have a world containing all the elements nessecary for life.

Abiogenesis:

This is the creation of life ("abiogenesis" refers to the creation of life from non-living matter).

The chemical elements crashing around on this Earth (whose origins lay in the stars) form into bigger chemicals, and those chemicals react with each other to form other chemicals. Eventually, a self-replicating chemical occurs (like a strand of RNA).

As well as that, membranous bubbles would be forming in the right environment - microscopic spheres similar to the bubbles formed when you pour detergent into water, only much much smaller. These bubbles could essentially act as little experiment tanks - imagine a whole series of bubbles, each with a slightly different chemical mix making it up.

The bubbles containing chemical mixes that enable them to remain stable will remain stable, and those with mixes enabling them to grow and split to make more versions of themselves will grow and split and make more versions of themselves. Self-replicating chemicals like RNA may start to become important here.

This is natural selection. Also important is that the descendants of successful spheres won't be exactly alike to their ancestors. They'll change. Once you have that and natural selection acting together, evolution begins.

To Be Continued... move forward in time to view a history of Australia