Jennifer Ouellete takes a timely dip into astronomical history: "Sic Transit Venus".
Kepler thought the next transit wouldn’t be until 1761, predicting a near miss in 1639. But Horrocks found an error in the great astronomer’s calculation and realized there would be a second transit, instead of a near miss, in 1639. Horrocks, at least, was ready with his little experimental set-up.
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Horrocks died suddenly at age 22, prompting his fellow astronomer and mentor William Crabtree, who had been very impressed with the young man’s abilities, to exclaim, “What an incalculable loss!” His observations weren’t published until 1661.
The kid who knew Kepler was wrong, and they publish him twenty-two years after the event. That's the least of the bad episodes that accompanied Venus transit observation over the years, people dying for astronomy. Ouellete also recounts the story of the man who survived two failures to see the transit, Guillaume Le Gentil. Of course, if we're going to rank fieldwork in order of risk, astronomy is nowhere near as bad as archaeology!