Cosmology - How big is the universe?

The size of the universe may well be infinite, but if we consider that part of the universe that is visible to us (the observable universe), then:
The diameter of the observable universe is: 93 billion light years across.

Note that we say diameter because the shape of the observable universe is a sphere centered on the point of observation, the earth.

A light year is the distance light travels in 1 year. About 6 trillion miles.
(Light travels at 299,792,458 meters per second, or 186,000 miles per second.)

Ads by Google

Ask a question, send a comment, or report a problem - click here to contact me.

© Richard McGrath