From what I understand, the only person to try this was Christian Huygens.On the basis of photometric comparisons which though rough nevertheless gave an order of magnitude, Huygens estimated that the distance of Sirius was about 27,000 that of the Sun (from earth). This is about 20-times too small but gave a good idea of how enormous the stellar universe was compared to the planetary one.

The basic idea is that, in a dark room during thedaytime, he punched a pinhole in a shade until the brightness of the sun's light through the pinhole was the same as the brightness of Sirius. He had to trust his memory to remember how bright Sirius appeared to him the night before!

Daylight represents the illumination of the Sun at the Earth at the distance between the Sun and the Earth. So, so long as he was standing far enough back from the pinhole that he could not resolve its size, his eye was receiving the samebrightness from the pinhole with the solar disk behind it, as it would from Sirius which was also unresolved.

To get the distance to Sirius in units of the Earth-Sun distance, you now haveto measure how far you are from the pinhole. The ratio of this distance to the pinhole diameter giving the same intensity as Sirius is then the distance toSirius in multiples of the Earth-Sun distance....27,000.

If you use a pinhole about 1 millimeter in diameter, you have to stand27 meters back from the screen. The angular size of the pinhole is 1/27000of a radian which equals 206265/27000 = 8 arc seconds in diameter. Human acuity is about 60 arcseconds so Huygen's was comparing apples with apples.(both the pinhole and Sirius were unresolved ).

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