Here’s a good one for the month that includes Halloween. Last May, my fiancee, Deborah Carter, and I were on Mauna Kea, Hawaii, just below the summit and its splash of telescopes. We stood on the shore of Lake Waiau in the rarified air at 13,000 feet (4,000 meters) altitude. The Sun was near setting, and as Deborah enjoyed a moment of solitude gazing into the lake, I sauntered off to take in the Mars-like terrain. On my return, Deborah looked perplexed, telling me of a weird phenomenon she observed.
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