I searched the forum, but I couldnt find the answer to my question. And sorry if this is in the wrong thread.(adsbygoogle = window.adsbygoogle || []).push({});

But anyway. I understand how a parsec works, when it comes to the simple trig behind it. But how do astronomers work out the angle opposite the radius of the earths orbit around the sun?

Thanks for any help. Alex

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# How a parsec works

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