Everything we know today- energy space and matter- came into existence about 13.7 billion years ago. In the beginning, the universe was very dense, hot and concentrated at in very small space. Within a few seconds of the huge explosion, many fundamental particles appeared.. Within a few million years.. as the universe cooled, the first atoms took birth..
The universe began expanding as time passed, to form the unimaginably huge cosmos we know today. It is believed that the universe is accelerating as it is expanding..which means that in a few billion years, it will be double a s large as it is now..
The first stars, which were formed only 200 million years after the big bang, were composed almost entirely of hydrogen and helium as no other elements existed back then..
It is believed that the very first stars were had a very large mass and hence, a short lifespan..They would have lasted only a few million years before dying as a supernovae..
My next post will be about the fate of the universe..Please take time to read it.
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