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light year it's a measure of distance

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and it's pretty straightforward the

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distance light can travel in a year but

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light travels fast

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one light year is about 5.879

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trillion miles or 9.461 trillion

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kilometers

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inches to measure distance why do we

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need light years

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well space is big like really big

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the nearest star to our solar system

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proxima centauri is about

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4.2465 light years away or 25 trillion

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miles and that's a close star so when we

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start talking about longer distances

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like to other galaxies we need bigger

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units of distance q light years

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and by the way it's not just light years

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there are also light seconds the

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distance light can travel in a second

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and light minutes how far light travels

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in a minute

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in fact our sun is about eight light

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minutes away from earth which means the

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sunlight you can see right now left the