Follow this link to skip to the main content

The Hidden Lives of Galaxies - How Big is the Universe?

Activity #1
How Big is the Universe?

The Milky Way has a radius of approximately 50,000 light years. The visible universe has a size of approximately 15 billion light years. If the Milky Way is represented by an 8 centimeter wide coffee cup, how big would the rest of the universe be in kilometers?

Galaxy, stars, and a coffee cup.

The Milky Way has a radius of about 50,000 light years.

What is the total size of the Milky Way Galaxy?________

The visible universe has a radius of approximately 15 billion light years.

So if an 8 cm wide coffee cup represents the Milky Way, the visible universe would be a sphere approximately ________km in radius.


  Show your calculations
 

What other objects can you use to compare the size of the universe with the size of the Milky Way galaxy?




 

A service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA/GSFC

NASA Logo, National Aeronautics and Space Administration
Goddard