When my generation was younger we were taught that the Earth was no more than 10,000 years old. We were fortunate enough to have an observatory at my school but it was used only by a very small group of “geeks” and “nerds.” Little did I realize at the time how knowledge of the universe would grow and how fascinating it actually is.
Scientists today calculate the earth as being 4.543 billion years old. When we look up at night and see the Milky Way it is hard to believe that it is 13.21 billion years old according to current science. Science would have been so much more interesting if we had the information linked below – click on the blue links for really fascinating information on the possible end of our universe.
In our universe, scientists can see about 10 billion galaxies. Obviously, the number of stars in a galaxy can vary greatly, but if we assume there are, on average, 100 billion stars per galaxy it would mean that there are about 1,000,000,000,000,000,000,000 (1 billion trillion!) stars in the observable universe. This amount is about equal to the number of grains of sand on ALL of the beaches on Earth!! That is a lot!!
The most popular current scientific consensus is that the ultimate fate of the universe depends on its overall shape, how much dark energy it contains, and on the equation of state which determines how the dark energy density responds to the expansion of the universe.
Recent observations find, from 7.5 billion years after the Big Bang, that the expansion rate of the universe has likely been increasing, commensurate with the Open Universe theory. However, other recent measurements by Wilkinson Microwave Anisotropy Probe suggest that the universe is either flat or very close to flat.
There are a few possible theories about how the universe will end:
- The universe will continue to expand forever;
- It will stop expanding and remain in equilibrium; and
- It will contract in on itself (known as the “Big Crunch“) in which the universe collapses, ending as a black hole, or causing a reformation of the universe starting with a new big bang.
If you want to read more about the ultimate fate of the universe, click here.