Do you know the distance in kilometers of 1 light year?

The light year, as its name implies, is the distance light travels in a vacuum over a year. As far as our discoveries allow us to go, the speed of light is the fastest thing ever known. For this reason, experts use light to calculate distances in the Solar System and other parts of the universe.

To give you an idea, the sun is eight light minutes from Earth and the moon is just a second light. It seems little, doesn't it ?! But if you think that the light we see from other stars takes a few hours to get here, maybe things will get a new perspective. And that brings some obstacles to communication, for example: a radio transmission from Mars to Earth (traveling at the speed of light) would take an average of 20 minutes to reach us.

In practice, one light year is approximately 9, 461, 000, 000, 000 kilometers. If we compare the distance between the center of the earth and the center of the moon - which is 384, 403 kilometers - that still looks like a little bug about a light year away. Another good example is Pluto, which at the farthest point of its orbit is only 7, 400, 000, 000 kilometers from the center of the Solar System.

To keep impressing with the numbers, just think that Alpha Centauri, which is the closest star to our system, is only 4.37 light years away. Andromeda, which is the closest spiral galaxy to the Milky Way, is about 2.5 million light years from here. Have you thought about converting all this into kilometers?

Because we think!

Responding to a suggestion from one of our readers, we decided to calculate the distance in kilometers and the time it would take to reach Kepler-186f, a newly discovered planet where NASA believes there could be life. For starters, we know that the new star is only 500 light years from Earth, which means that traveling at the speed of light would take 500 years to get there.

But if we convert this distance to a more familiar measure we will find the surprising number of 4, 730, 500, 000, 000, 000 kilometers. With yet another set of rules of three and mathematical operations, we came to a conclusion: If you traveled at 200 km / h, it would take just over 2.7 billion years to get to the Kepler-186f. This is time for hell, isn't it ?!

Although light years are convenient enough to think about how things happen on a truly grand scale in the universe, astronomers use another unit of measurement: parsec, which is about 3.26 light years. “It's a unit of distance that makes the most physical sense of how we measure distances, ” says astronomer Nicole Gugliucci.

* Posted on 5/1/2014