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LAHLH

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OK, maybe this is a silly question but, if you look at the sky in a program like Stellarium say, and then look north, why can you see stars at points on the celestial sphere corresponding to points on the other side of Earth from where you are?

I hope this question is clear, what I mean is the celestial sphere is a projection of each point on the Earth outwards to an imaginary sphere at infinity; let's say you're 40 degrees north and on the prime meridian, then you look northward into the sky, why then projections from 180 degrees longitude and 20 degrees lat visible to you (so 20 degrees ascension...but projected from 180deg around long wise)

I would have thought the pole star would have appeared just above my horizon as I looked north, not high up, and I wouldn't have imagined I would have been able to see any stars corresponding to points on Earth that are 180 degrees around (longitude) from me...

hope that makes sense...maybe it has something to do with the projection being infinite distance away..

I hope this question is clear, what I mean is the celestial sphere is a projection of each point on the Earth outwards to an imaginary sphere at infinity; let's say you're 40 degrees north and on the prime meridian, then you look northward into the sky, why then projections from 180 degrees longitude and 20 degrees lat visible to you (so 20 degrees ascension...but projected from 180deg around long wise)

I would have thought the pole star would have appeared just above my horizon as I looked north, not high up, and I wouldn't have imagined I would have been able to see any stars corresponding to points on Earth that are 180 degrees around (longitude) from me...

hope that makes sense...maybe it has something to do with the projection being infinite distance away..

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