(Like I may have mentioned. He was good at explaining things. And making people laugh!)
The Big Bang Theory
As explained by Rob -
Most astronomers believe the Universe began in a Big Bang about 14 billion years ago, I on the other hand as I have explained believe it started as a squashed peach. At that time, the entire Universe was inside a bubble that was thousands of times smaller than a pinhead. It was hotter and denser than anything we can imagine.
Now read that sentence again if it makes sense to you read on.
Then it suddenly exploded, apparently or imploded either way the Universe popped into existence. The Universe that we know was born. Time, space and matter all began with the Big Bang. In a fraction of a second, the Universe grew from smaller than a single atom to bigger than a galaxy. And it kept on growing at a fantastic rate. It is still expanding today. It grew faster than Heliums readership, faster than Gordon Browns hair falls out, faster than the links to adult sites are growing on blogspot, and even faster than me chasing a rare tram ticket.
As the Universe expanded and cooled, energy changed into particles of matter and antimatter. I say cooled its all relative as Einstein would say most of it is still pretty f*ing hot e.g. The Sun. These two opposite types of particles largely destroyed each other, like you do. But some matter survived (phew!). More stable particles called protons and neutrons started to form when the Universe was one second old.
Hang on a moment did this all take place in one second then?
Yep I've checked that's what Ladybird says all right. -
Over the next three minutes, the temperature dropped below 1 billion degrees Celsius around the temperature of a McDonalds Coffee. It was now cool enough for the protons and neutrons to come together, forming hydrogen and helium nuclei though I do not know why and I have been unable to find out. My Ladybird does not cover it. .
After 300 000 years, the Universe had cooled to about 3000 degrees. Atomic nuclei could finally capture electrons to form atoms. The Universe filled with clouds of hydrogen and helium gas. These were not much use to anyone unless you want to speak in a squeaky voice or inflate balloons and as no one existed yet and balloons had not been invented it just floated there filling up space.
We cannot see anything that happened during the first 300 000 years of the Universe. Scientists try to work it out from their knowledge of atomic particles and from computer models. They are also reading the signs in tea leaves and getting info off dodgy conspiracy theory web sites as well.
The only direct evidence of the Big Bang itself then is a faint glow in space. Spacecraft and telescopes on balloons see this as a patchy pattern of slightly warmer and cooler gas all around us. These ripples also show where the hydrogen clouds were slightly denser. In 2001 a manned space mission named "Operation Faint Glow" travelled to the area to discover it was in act a Baby Belling electric fire with one bar left on.
As millions of years passed like an evening watching Channel 5, the dense areas pulled in material because they had more gravity. How did they get more gravity you ask? I do not know. Finally, about 100 million years after the Big Bang, the gas became hot and dense enough for the first stars to form, and for the first gas bill to be issued. .
New stars were being born at a rate 10 times higher than in the present-day Universe, things were always better in the old days. Large clusters of stars soon became the first galaxies. After this coincidence it soon became a convention to name things in space after chocolate bars, like Milky Way and Mars.
Hubble's newest camera eyes hotbed of star formation says the caption. It looks like an inkblot test to me or a cross section of an alcoholics liver.
The Hubble Space Telescope and powerful ground-based telescopes are now beginning to find galaxies that were created about one billion years after the Big Bang, most people had no idea they were lost but there you go. . These small galaxies were much closer together than galaxies are today meaning that a single day return was possible if you needed to pop there for a bit of shopping . Collisions were common similar to the M25. Like two flames moving towards each other, they merged into bigger galaxies. Our Milky Way galaxy came together in this way.
Not long after that human beings evolved and started inventing things like buildings, aeroplanes and huge flying telescopes.