3 ms·
Well, there's this: https://en.wikipedia.org/wiki/Large_Zenith_Telescope https://en.wikipedia.org/wiki/Large_Zenith_Telescope (I'm not sure how much Mercury th
by yongjik 11y ago
Well, there's this: https://en.wikipedia.org/wiki/Large_Zenith_Telescope https://en.wikipedia.org/wiki/Large_Zenith_Telescope
(I'm not sure how much Mercury the telescope uses.)