Prediction of death. Mark Twain kind of predicted his death. In 1909, he said: ‘I came in with Halley’s Comet in 1835. It is coming again next year, and I expect to go out with it. It will be the greatest disappointment of my life if I don’t go out with Halley’s Comet. The Almighty has said, no doubt, “Now there are these two unaccountable freaks; they came in together, they must go out together”.’ He died of a heart attack on 21 April 1910 – one day after the comet had come again and appeared at its brightest. Halley’s comet only passes by Earth approximately every 76 years and has been the subject of a string of predictions since 1705.