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In the night sky: Orion
In the night sky: Orion

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2.1.3 How far away is the Orion nebula?

How far away is the Orion Nebula? An ‘astronomical’ distance would be a good description!

It is estimated to be about 1600 light years away. It may sound a bit odd, to use time as a measurement of distance, but as Monica explains in the video, that is because the distances are so large. A light year is the distance light travels in one year. We can calculate what that is in kilometres or miles, as you can see in the following video.

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So light travels about 9.5 million million kilometres, or 6 million million miles in a year.

If the Orion Nebula is 1600 light years away, that is 1600 x 9.5 million million kilometres – the best part of 15.2 thousand million million kilometres or about 9.6 thousand million million miles – which is quite far away. And also explains why astronomers use light years as a unit of distance.