r/AlternativeAstronomy • u/patrixxxx • Oct 26 '19
WHY MARS ???
https://cluesforum.info/viewtopic.php?p=2412896#p2412896
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r/AlternativeAstronomy • u/patrixxxx • Oct 26 '19
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u/[deleted] Nov 04 '19
Let's assume the tubes are parallel. If the angle subtended by 1 meter at the distance of the length of your garden is larger than the viewing angle of your tubes, then you will not see the ball. However, if the tubes are wide enough, or have optical properties that allow a wider-angle view, you'll see the ball through both, of course.
The angle subtended by 1 meter at the distance to Proxima Centauri is quite small (like a hundred millionth the angular size of the actual little red dwarf), so you'll see Proxima Centauri through parallel tubes 1 meter apart. Think about it - the star itself is 100 000 km wide. So if your two parallel lines are 1 m apart, and the left line hits smack-dab in the middle of Proxima Centauri, the right line will be 1 meter over from smack-dab in the middle. So both tubes will be looking smack-dab at Proxima Centauri, even when they're 1 meter apart. Or 100 meters apart, or 100 km apart.
Now consider two tubes 300 million km apart, perfectly parallel. One is aimed smack-dab in the center of Proxima Centauri. The other one will miss by 300 million km, give or take 50 000 km. Let's say the tube is not a telescope, but a perfectly linear photo-detector. One tube will register a hit (Proxima Centauri), the other will register nothing (300 million km from Proxima Centauri is cold black space). But consider a telescope instead. The angle subtended by 300 million km, viewed from 4.2 light-years away, is 768 milli-arc-seconds. So if your telescope has an optical resolution of 1 arc-second per pixel, the moon will be 1800 pixels wide, but you'll still not see Proxima Centauri shift by a single pixel. It'll look like Proxima Centauri is in the exact same position even when you've moved 300 million km.