So we are not completely sure how the universe began but we have some ideas of what could had be going on right at the beginning. We think it began at the Big Bang when everything we see now in space was usually condensed down in this very small region smaller than an atom would had blown up to bigger as the sun and we see how began the universe and began the expansion of the universe the universe then expanded and cooled down quite a lot until at a certain point atoms can now form.. We got to believe these things about the early universe because we actually have observations because we measure light thats been traveling and so even if we look at the sun for example the light from the sun set off 8 minutes ago if we look further back in space we could look back even further and we could actually look back as far as this time that was only a few hundred thousand years of the BIG BANG BANG, BANG, BANG, BANG, BANG, BAANNGG we can measure light from that time and we can see how the universe looked back then at the beginning of the universe, the universe was so hot that atoms were split up into electron and a proton and it would been like a soup or bit like a cloud ..that atoms can form together and light could just travel out through space BANG, BANG, BANG, BANG, BANG, BAANNGG This light thats been traveling for almost fourty billion years instead of a few hundred thousand years of the BIG BANG It travels through space A different kind of light, microwave light, such there are its micro waves this light hitting us from all directions of the sky everywhere we look the temperature of this light is about minus 270 degrees, its really cold BANG, BANG, BANG, BANG, BANG, BAANNGG The idea is, if this is an area of space thats got a little more stuff in it than another area, so its a little bit more densed as somewhere else, than that is be able to start growing Gravity does its job so you have a region of space that is more densed Gravity will act to pull in more stuff around that area until you got have enough stuff and it could start to collapse and make objects like the first stars by measuring this patterns and these ripples we can figure out how much of the universe is made off different materials so we can work out how much of it is normal stuff that we are made off and how much of it is weird stuff, that we dont understand and that is the stuff we call dark matter Dark energy BANG, BANG, BANG, BANG, BANG, BAANNGG Dark energy we also have made a better estimate of how fast the universe is expanding so you have some some energetic initial Big Bang that starts its expansion and then for ever more stuff in the universe should tend to slow down expansion cause gravity kind of pulls in and tends to slow the things down so we always really thought that the universe keeps slowing down and slowing down forever more but we have now discovered the last 15 years that there is this mysterious dark enery around and that is now making the universe speed up again so the expansion is now speeding up but its doing it for the last billion years but the weird thing about dark enery is it seems to grow BANG, BANG, BANG, BANG, BANG, BAANNGG BANG, BANG, BANG, BANG, BANG, BAANNGG So we are in this lucky situation that we think we can track the universe all the way through its 40 billion year history and the Big Bang to were we are today our universe full of galaxies about 5 billion years ago we then had our own solar system beginning to form it started off with an own sun coming to live also its a very normal star then gradually our solar system formed then around that star this big disk of dust and rocks and junk that eventually combined together to form planets and thats now been there for the last few billion years our own sun has about 5 billion years left to live so we got a while yet