What Is a Light-Year?

Do you know what it is that a light-year actually measures? Do you know why so many people find it confusing? And why they really shouldn’t?

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Have you ever heard somebody say that something is light years ahead of its time? Or that some product they’re trying to sell you is light years beyond its competition? Or maybe your kids like to complain in the car that the fun and relaxing family road trip you’re taking isn’t so fun and relaxing because it’s taking light years to arrive at the land-o-fun?


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I think we’ve pretty much all heard the term “light year” used in one of these ways at least once in our life. And on each of those occasions, the term was used incorrectly. What’s the problem? Where did all of these hypothetical people go wrong with their use of the lingo? And what does the term light year actually mean? Let's find out.

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