Happy Winter Solstice to all! In the northern hemisphere, today is the shortest day and the longest night of the year. The sun is at its southernmost point of travel, over the imaginary circle on the globe we refer to as the Tropic of Capricorn. Today is also the day in which a person standing outside at noon in the northern hemisphere, outside of the tropics, would cast the longest shadow. If you are on the Tropic of Capricorn, however, at noon today, you would have no shadow at all.
Reading an article in The Sailors’ Magazine and Seamen’s Friend, Volume 43, Issue 3, of 1871, got me thinking about shadows and the solstice. (I will admit that this is more than a touch odd.) It seems that at an 1871 gathering at the Chicago Academy of Sciences, a Rev. Mr. Miner, of Canada presented a paper called “The Snow Line” in which he observed, “Should a man start from the Tropic of Cancer at the winter solstice and walk 18 miles per day northward for six months, his shadow would remain nearly the same each day at noon.” If instead of starting at the Tropic of Cancer one began at the Tropic of Capricorn, you might do away with your noon shadow altogether.
Between the winter and summer solstices, the sun does moves overhead roughly 15 nautical miles (or in the Rev. Mr. Miner’s terms, 18 statute miles) north or south each day. If one was to stand directly on the Tropic of Capricorn, on the northern hemisphere’s winter solstice at noon, one would not cast a shadow. The sun would be directly overhead. If you walked or sailed north for just over 15 nautical miles, you would once again at noon, cast no shadow. And so on, until you reached the Tropic of Cancer on the northern hemisphere’s summer solstice. At which point if you turned south and repeated the process you could be shadowless, at least at noon, indefinitely.
In some Buddhist teachings, being without a shadow can indicate that one has achieved nirvana. In Western lore, lacking a shadow is a characteristic of being a vampire or a lycanthrope. I suspect if you spent too much time in the Tropics with the sun constantly overhead at noon, all you might become is a victim of sunstroke.
Fortunately, while today’s sunlight may be short and the darkness long, at least sunstroke is less of a concern. Again, may you have a most Happy Solstice!