How big is the universe?

We can observe only a portion of the entire universe. Because the universe is only about 14 billion years old, light has only had about 14 billion years to travel through it. Therefore, the most distant regions of the universe we can see are about 14 billion light-years away. This is the extent of the "observable universe," but the entire universe is probably much larger. It could even extend infinitely in all directions.

HubbleSite and STScI are not responsible for content found outside of hubblesite.org and stsci.edu

Next question: In what sense is the universe expanding?

Previous question: How old is the universe?

See all questions and answers on one big page.

Return to question list for Cosmology

Return to FAQ home