February 7, 2000

Letters to the Editor
Sky & Telescope

Dear Mr. Editor

Backyard Analemma

Some 20 years ago I paid a visit to my parents in law in Viña del Mar, Chile. Looking down at the floor of their patio I saw a string of red dots in which I recognized a partial analemma. When I mentioned the fact to my father in law, a retired navy officer, he told me that to check the accuracy of his watch, every day at noon he came down to the patio and marked with red paint the place of the shadow of the upper corner of his house. He was puzzled why the dots did not fall on a straight line, running from north to south. I explained him the equation of time, and told him to be careful when we shifted from summer to winter time. He followed my advice and after some months he had in his yard a beautiful analemma about 3 meters in size, including most of the days of the year. He was very pleased to see the same shape in the cover of your June 1979 issue.

If any of my readers is usually at home around noon and has a suitable house, he can have his own personal analemma in this way.

Eduardo Vila-Echagüe
Santiago, Chile
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