"The fate that awaits all astronomers"

Aaron made some mighty plans for observing the Transit of Venus, but his plans were thwarted. Condolences to him, of course. But then, he's in pretty good company, for the ultimate in astronomical bad luck has to go to one Guillaume le Gentil, who met with disastrous results in trying to observe the transits of 1761 and 1769.

For the first transit, he planned to do his observing from the eastern coast of India, but his ship was blown off course by monsoons and he was stuck at sea on transit day. Deciding to wait the eight years for the second one, he built his own observatory, and in 1769 an entire month of crystal-clear skies led right up to the morning of the transit -- whereupon the skies immediately clouded over for the duration of the transit.

And then, le Gentil's return journey to France was so fraught with hardship that when he finally arrived home, he learned that he had been declared dead and his entire estate dispersed.

Now that is some bad luck.

(Account of Le Gentil's experience drawn from Timothy Ferris's excellent Coming of Age in the Milky Way.)