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/ Source: TODAY
By Jenna Fratello

Age really is but a number. On last night's episode of "America's Got Talent," John Hetlinger proved that you're never too old to chase your dream.

The 82-year-old crooner rocked the house with his rendition of Drowning Pool's "Let the Bodies Hit the Floor," stunning all four judges with his headbanging moves and intense vocals.

Instantly, the shocked crowd went wild with cheers of disbelief. Judge Howie Mandel even gave the unlikely singer a standing ovation.

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Before his rocker days, Hetlinger, a native of Broomfield, Colorado, worked in aerospace engineering as a program manager for the COSTAR instrument that repaired the Hubble Space Telescope. Prior to that, he was also a Navy pilot - something that he says was "far enough into space."

"That's incredible," judge Simon Cowell remarked, before asking why Hetlinger decided to come on the show to perform after such an illustrious professional life.

"This would be the high point of my life and many careers," Hetlinger said.

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It wasn't until after his retirement 15 years ago that Hetlinger began to do karaoke — and fell in love with entertaining people.

You can watch the rest of his karaoke renditions on his personal YouTube account, along with another impressive performance of "Bodies" like this one:

Rock on!