All Questions
5 questions
2
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1
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What exactly is a Hamiltonian telescope? Is this one?
This comment on the current answer to Why is this telescope so short? How hard is it to make such a fast primary? says
In this forum topic Borisov appears to call it an f/1.5 Hamiltonian.
Wikipedia'...
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4
votes
0
answers
157
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How did Michelson measure the diameters of jupiter's moons using optical interferometry?
In Betelgeuse: How its Diameter was measured (Chant, C. A., Journal of the Royal Astronomical Society of Canada, Vol. 15, p.133, Bibliographic Code: 1921JRASC..15..133C) the author says:
The paper in ...
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4
votes
2
answers
1k
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How does making a refracting telescope very long reduce the chromatic aberration of an uncorrected lens?
Below are two cropped views of "Johannes Hevelius's 8 inch telescope with an open work wood and wire "tube" that had a focal length of 150 feet to limit chromatic aberration." from ...
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2
votes
3
answers
750
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How did Johannes Hevelius' long telescope work? Why all the round holes?
The drawing below, found in Wikimedia and at lib.harvard.edu is of a very long tubed aerial telescope. I believe it is taken from his 1673 work Machinae coelestis.
I've always wondered about the ...
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17
votes
5
answers
2k
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Has anyone ever tried to make a simple telescope using ice?
I grew up with long cold winters, and saw a lot of remarkably transparent ice formed by refreezing meltwater, both in puddles and ponds, and in large icicles. I'd always thought about making optical ...
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