Hello!

I would like to know, when did humans realize that there are another galaxies? 

I have heard that it was when Hubble discovered, that Andromeda's nebula is The Andromeda Galaxy, but as I know, Hubble was launched in 1990 and I can't believe that we thought, that our galaxy is alone till that date (1990+).

8 minutes ago, hamburger228 said:

Hello!

I would like to know, when did humans realize that there are another galaxies? 

I have heard that it was when Hubble discovered, that Andromeda's nebula is The Andromeda Galaxy, but as I know, Hubble was launched in 1990 and I can't believe that we thought, that our galaxy is alone till that date (1990+).

You are right. It was Edwin Hubble, who discovered in 1923 that those spiral nebulae were much farther away than one previously thought. The Hubble telescope is named after him.

1 minute ago, Eise said:

You are right. It was Edwin Hubble, who discovered in 1923 that those spiral nebulae were much farther away than one previously thought. The Hubble telescope is named after him.

Thank you a lot! I was so confused with that information.

Here is a reprint of the great debate prior to Hubbles work.

http://apod.nasa.gov/diamond_jubilee/debate20.html

Which occurred in the 20's

Edited May 26, 20187 yr by Mordred

7 minutes ago, Mordred said:

I don't know the exact date but it was some time after the Great debate.

http://apod.nasa.gov/diamond_jubilee/debate20.html

Which occurred in the 20's

Have heard of the great debate...From my somewhat at times faulty memory, [only excuse is I'm an old bastard now] Hubble and others were trying to discertain the makeup of numerous "cloudy nebulae" M31 being one of those. Working with the Mnt Wilson 'scope, the largest at that time, he was finally able to discertain individual stars in the M31/Andromeda nebula. From that, and after examining other of these nebulae, it was found that the stars that make them up, were many times further away than any star within the Milky Way galaxy. 

 Correct it was an interesting read so I kept a link to Jubilee reprints on my site. My 1921 physics textbook never mentioned other galaxies either lol.

 Though its model of the atom was protons and electrons no neutron...

Edited May 26, 20187 yr by Mordred