The Galaxies

How They Came to Be

How Many Are There?

Our Milky way is a vast galaxy filled with 200 to 400 billion stars and Lord knows how many Solar Systems and planets! But, how many galaxies are actually out there? It's been estimated that there is possably 100 to 200 billion galaxies, but, according to a German supercomputer, it has been recorded as of recent to be at least 500 billion galaxies! But, these are only rough estimates. We may never know how many galaxies are really out there.

How Do We Know?

Like I said, these are only rough estimates! But, to make these estimates, astronomers have to use very powerful telescopes, like the Hubble Space Telescope, so that they can deeply study our universe. These astronomers count up all the galaxies in the cone of space that makes up the deep image, and they then use this as an average for the rest of the sky. Though they are only seeing a small fraction of space, they can estimate the rest.

How Were They Created?

The Big Bang Theory

To be able to understand how galaxies were created, you have to be able to understand the Big Bang Theory. The Big Bang is said that it happened about 14 billion years ago, when the universe was created by a single violent event.

The Galaxies Formation

It is said that the galaxies started to take shape about one billion years after the Big Bang which took place 13 to 14 billion years ago. There are two theories that are probably the most leading theories that explain how they were created. One of these theories says that they were created where vast clouds of gas and dust collapsed under their own gravitational pull, then letting the stars form. The other says that small "lumps" of matter clumped together, creating the galaxies.

Bibliography

"How Many Galaxies in the Universe." Universe Today. 4 May 2009. Web. 1 June 2015.

"The Big Bang - NASA Science." The Big Bang - NASA Science. Web. 1 June 2015.

"Galaxy Formation." Galaxy Formation. Web. 1 June 2015.