Happy Birthday, Stephen Hawking! Famed Scientist Turns 73 Today
Dr. Stephen Hawking speaks during NASA's 50th Anniversary celebration, April 21, 2008, at George Washington University's Morton Auditorium in Washington, DC.
Credit: NASA (via Flickr as NASA HQ PHOTO)

World-renowned theoretical physicist and cosmologist Stephen Hawking celebrates his 73rd birthday today (Jan. 8). 

Hawking isn't a rock star in the Elvis Presley sense of the word (Hawking and Presley share the same birthday), but Hawking is considered a rock star in the science community for his work with black holes, where he combined the principles of the small world of quantum physics with the huge world of Einstein's general relativity.

"No one had done that before," Neil deGrasse Tyson said in a video explanation of Hawking's theory. "That's badass."

Hawking has ALS, a degenerative motor neuron disease that attacks the neurons that control muscle movement. He was first diagnosed at the age of 21, and his doctors told him that he had two years to live. Hawking's science career took off even as the disease progressed, and he continued working and teaching even when the disease eventually landed him in a wheelchair and took away his ability to speak. Hawking has defied the odds of his disease, and he now communicates using a single cheek muscle and a computerized speech-generator.

A biopic film released in November, 2014, called "The Theory of Everything", reveals Hawking's personal life and his struggle with the disease. [Watch 'The Theory of Everything' Trailer]

"The Theory of Everything" is nominated for four Golden Globes, including best dramatic picture and best score. Actress Felicity Jones who plays Hawking's first wife, Jane, is nominated for best actress. Actor Eddie Redmayne who plays Stephen Hawking is nominated for best actor. Hawking was impressed with Redmayne's performance in the film.

"At times, I thought he was me," Hawking wrote in a post on his Facebook page.

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