How do we know how many galaxies there are in the Universe?

How many galaxies are in the Universe? How do we know?

Take a tour of the most distant galaxies ever photographed in the Universe, as seen through the eyes of the Hubble Space Telescope!

Explanation and narration by theoretical astrophysicist Ethan Siegel, of http://scienceblogs.com/startswithabang/

Full sources of images and videos used in the creation of this available here: http://scienceblogs.com/startswithabang/2011/10/how_do_we_know_how_many_galax...

Category:

Science & Technology

Tags:

• Universe
• Space
• astronomy
• Hubble
• galaxies
• telescope
• physics

[w00tehpwn]

Sweet, I finally get to listen to one of my favorite (and most awe inspiring) science bloggers!

[Coles109]

i wanna travel the universe far far away and see the end of the universe or something.

[NewDie9]

How many galaxies are there: 10

[loxspliff1]

900 billion galaxies,

there you guys go

[Cloyde100]

They don't.

[Coles109]

@tomagotchii Hahaha yeah that would be awesome! Ima do the same. lets go get permission when we die :)

[tomagotchii]

@Coles109

always told myself if i die and go to heaven i would ask God can I fly throughout the universe to see life or whatever there is out there. since i'm already dead and nothing else can kill me. I'll just be a lonely angel flying through space.

[pageoneable]

Thanks, Ethan, for a terrific, understandable short presentation of this awesome topic. I have FB's and +1'd with the following copy, hoping it's accurate: "Over our heads are some 100,000,000,000 galaxies - a mindblowing number only recently arrived at by astrophysists. In less than 5 minutes, this short video explains in plain English and with rich imagery how they counted them all up. So far."

[CognosSquare]

Mind blown. Great video.