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0 pointsOnACoffeeBreak6y ago0 comments

Yep, I meant to write diameters.

> From Earth, solar radius = 0.25 degrees. 233 solar radii in 1 radian.

I don't understand this. I think I understand that the sun would take up 0.5 degrees of the "view" (I don't have a good word for this) when looked at from Earth, so radius is 0.25 degrees. But how does the second statement follow? I get that a radian is about 57.3 degrees, so 57.3 / 0.25 = 230, but why why does 1 radian make sense to use here?

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iclelland6y ago

An arc that spans one radian of a circle's circumference has the same length as the radius.

So if you imagine a connected line of 233 suns across the sky, spanning 57.3 degrees, the actual length of that line would be the same as the distance from your eyes to the sun.

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0 pointsOnACoffeeBreak6y ago0 comments

Yep, I meant to write diameters.

> From Earth, solar radius = 0.25 degrees. 233 solar radii in 1 radian.

0 comments

iclelland6y ago

An arc that spans one radian of a circle's circumference has the same length as the radius.

So if you imagine a connected line of 233 suns across the sky, spanning 57.3 degrees, the actual length of that line would be the same as the distance from your eyes to the sun.

j / k navigate · click thread line to collapse