Well, there&#x27;s this: <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Large_Zenith_Telescope" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Large_Zenith_Telescope</a><p>(I&#x27;m not sure how much Mercury the telescope uses.)