Science Of...

Just One Parsec Is Equal To 19 Trillion Miles (31 Trillion Km)

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Now, hang on just one parsec... Though a parsec may sound like a derivative of "second," it's not. And that's why the famed line about the Millennium Falcon in Star Wars—"It's the ship that made the Kessel Run in less than 12 parsecs"—doesn't make sense. A parsec is a unit of measurement, not a unit of time. Sorry, Han. More specifically, one parsec is equivalent to 3.26 light years, or 19 trillion miles (or 31 trillion kilometers). If this seems excessively large, that's because it is. But when it comes to measuring astronomically large distances between objects beyond our Solar System, excessively large is just right.

The word itself comes from two words: parallax and arcsecond. Parallax describes when something's location seems to have changed because your location changed, while arcsecond is the measurement of an angle. Putting it altogether, a parsec is the parallax of one arcsecond, a statement which requires some trigonometry to fully understand. To give an example of this huge distance, the betelgeuse star, the ninth-brightest star in the night sky, is only 196 parsecs away. Learn more about this huge measure of distance in the video below.

What Is A Parsec?

Warning: This video might blow your mind.

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Defining A Parsec

A lightyear is a long distance; a parsec is more than triple that.

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How Big Is The Universe?

Please express your answer in parsecs.

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