At age 55 and married with two teenage kids, the esteemed astrophysicist might not seem like the typical heartthrob. But truth be told, he has a host of admirers.
"It started about 14 years and 25 pounds ago," Tyson tells PEOPLE. "In 2000, I was featured in PEOPLE's Sexiest Man Alive issue as the Sexiest Astrophysicist." Despite the accolade, "I didn't get big-headed about that," Tyson says, laughing. "You know, considering the category, it's not like I was the sexiest action star or anything."
Nowadays, Tyson, whose new show on Fox and National Geographic takes viewers on a virtual tour through the universe, says he encounters a number of starstruck admirers, mostly via Twitter.
"I'll Tweet something that's interesting and a little bit mind-blowing, and I'll get responses like, 'I just had a nerd-gasm,' " Tyson quips with a chuckle. "I say, whatever gets people interested in the universe! I'm happy to serve as a conduit to the cosmos."
But of course, there's a scientific explanation behind his fans' affection.
"When you tell people something that's intellectually delectable, they can feel sensually towards it," says Tyson. "But I think at the end of the day, the object of their affection is the universe."
Aside from being swoon-worthy (scientifically speaking), Tyson says he's just happy to be doing what he loves.
"I'm an educator and a scientist, and the show allows me to educate the public about science," he says. "What more could I ask for?"