Happy Birthday Stephen Hawking!

Today we celebrate the 67th birthday of Professor Stephen Hawking, perhaps the most brilliant mind alive today. He's been one of the greatest contributors to advanced physics and cosmology over the last half century, even after having been wheelchair bound for many years because of Lou Gehrig's Disease. At the same time, he has been a tireless advocate for scientific research all the while reaching out to involve the public. His book, A Brief History of Time stayed on the London Sunday Time's best sellers list for 237 weeks straight, making it the most popular physics book in history.

He first exploded on the scene in the late 1960s by helping to prove that black holes, massive gravity wells in space named because not even light can escape, were predicted by Albert Einstein's general theory of relativity. At the center of every black hole is what's called a singularity, an infinitely small and infinitely dense point in space that gives the black hole its mass. Hawking realized that the laws surrounding a black hole's singularity would be the same as the laws of the point at the center of the Big Bang, out of which the entire cosmos emerged. This breakthrough pushed the study of the beginning of the universe ahead immensely.

Just a few years later in 1974, Hawking again turned the study of black holes on its head when he found that black holes weren't completely black after all. He found that because of quantum field theory, black holes had a small temperature which emits energy, dubbed Hawking Radiation. More recently Hawking has been splitting his research between predicting the ultimate fate of the universe, and fleshing out String Theory in hopes of unifying quantum mechanics and general relativity once and for all.

When Hawking was 21, doctors diagnosed him with amyotrophic lateral sclerosis (ALS) commonly known as Lou Gehrig's Disease. The condition causes the nerves between the motor center of the brain and body to break down, causing the gradual loss of all muscle control. At the time doctors gave Hawking only about 3 years to live, that was 46 years ago. He has since been confined to a wheelchair and lost the use of his voice, but his mind is as brilliant as ever. Communicating through a computerized voice synthesizer, Hawking has written numerous books for everyone from the advanced physicist, to the general public, and even a new series of kid's books. He's become a sort of physics celebrity having appeared in numerous TV shows including Star Trek: The Next Generation, The Simpsons and Futurama. In 2007 he even took the time to float around in zero-gravity. Last year he announced that he was leaving the Lucasian Professor of Mathematics at Cambridge University, a post once held by Isaac Newton. He'll stay on at Cambridge as a Professor Emeritus, and is far from retiring. He's said his schedule is already booked up through 2012.