Adam Riess, astrophysicist

The prediction that the world would end on December 21, 2012. The latest data suggest that the universe has at least 30 billion good years left; the sun, 4 billion to 5 billion. As for the Earth, its life span depends on how well we take care of it.

Paul Offit, author, Bad Faith: When Religious Belief Undermines Modern Medicine

In 1916, Madison Grant, a New York lawyer, published The Passing of the Great Race, predicting that the Nordic race in America would be diluted by Europeans of lesser stock. Grant’s book set the stage for the American eugenics movement, which ultimately resulted in 65,000 sterilizations. When the book was translated into German, a young Adolf Hitler sent Grant a letter: “This book is my Bible,” he wrote. He would later take eugenics to its illogical end.

Janet Browne, author, Charles Darwin: A Biography

Thomas Bell, the president of the Linnean Society of London, summing up the year 1858 (which included the announcement of Charles Darwin and Alfred Russel Wallace’s theory of evolution by natural selection), stated, “The year which has passed has not, indeed, been marked by any of those striking discoveries which at once revolutionize, so to speak, the department of science on which they bear.”

James Randi, magician and author, The Mask of Nostradamus

Since 1964, I’ve offered a monetary prize to anyone who can demonstrate paranormal powers. So far, nobody has been successful. The world-renowned prophet Jeane Dixon predicted decades ago that “in the mid-’80s” a massive comet would strike the Earth, by which time the U.S. would also have a female president. Perhaps she meant the mid-2080s? We’ll see …

Dmitry Itskov, founder, 2045 Initiative

In 1950, in The Martian Chronicles, Ray Bradbury predicted a necessary colonization of Mars in the early 2000s due to a global nuclear war that would render the Earth unlivable. Fortunately, that didn’t happen. He reportedly explained years later why humanity hadn’t colonized Mars: “It chose consuming instead—drinking beer and watching soap operas.”

Mario Livio, astrophysicist and author, Brilliant Blunders

In April 1900, the Irish-born physicist Lord Kelvin proclaimed that our understanding of the cosmos was complete except for two “clouds”—minor details still to be worked out. Those clouds had to do with radiation emissions and with the speed of light, and they pointed the way to two major revolutions in physics: quantum mechanics and the theory of relativity.

Nicholas Campion, director, Sophia Centre for the Study of Cosmology in Culture, University of Wales at Trinity Saint David

Many people have predicted the end of the world over the past few thousand years, and it finds a distinguished place in the Book of Revelation. But it hasn’t happened yet, and is unlikely to anytime soon.