How Far is a Lightyear in Miles?

by Fraser Cain on June 1, 2010

Want to stay on top of all the space news? Follow @universetoday on Twitter

How Far is a Lightyear in Miles

The Crab Nebula

If you’re planning a trip to the nearest star, and you know it’s 4.3 light-years away, how far is 1 lightyear in miles? As you probably know, a lightyear is the distance that light travels in a single year.

Light is moving at a rate of 670,616,629 miles per hour. It only takes a second for light to reach the Moon, 8 minutes to get to the Sun, and just a few hours to reach the outer planets. Over the course of a year, light travels 5.87849981 x 1012 miles. Written out, that’s 5,878,499,810,000 miles – 1 light year in miles.

We’ve written several articles for Universe Today about measuring distances in the Universe. Here’s an article about 1 light year, and here’s an article about the closest galaxy to the Milky Way.

If you’d like more amazing photographs, the best place to look is NASA’s Astronomy Picture of the Day. I also recommend you check out the website for the Hubble Space Telescope.

We’ve recorded many episodes of Astronomy Cast, including one about Hubble. Check it out, Episode 88: The Hubble Space Telescope.


Fraser Cain is the publisher of Universe Today. He's also the co-host of Astronomy Cast with Dr. Pamela Gay.

Comments on this entry are closed.

Previous post:

Next post: