Pharrell Williams of "Happy" fame says the Cosmos  star makes him feel gratitude. (Photo by Jason Merritt/Getty Images for iHeartMedia)

When Pharrell Williams arrives backstage at one of his packed shows, the singer-songwriter expects a few things to be waiting for him. A full-length mirror, some Pedialyte, plenty of Red Bull -- and a framed picture of astrophysicist Carl Sagan.

[A fantastic idea Carl Sagan showed Johnny Carson in 1976 is about to become reality]

The Smoking Gun recently pulled this odd request out of Williams's rider -- the list of requirements a venue has to fulfill when an artist comes to perform there -- but it's no quirky secret. The singer himself gave Sagan a shoutout back in 2013.

But if you don't follow Williams on Instagram, this might be news to you. And it does sound pretty strange. A picture of an astrophysicist? That's what you need in your dressing room, along with your favorite foods, candies, and toddler-friendly electrolytes?

It's just a testament to how much of an impact Sagan made on the public during the course of his life: His television show "Cosmos," which aired in the 1980's, spun fantastic science for a popular audience. Some scientists side-eyed Sagan for his willingness to cater to the public interest, but it turned out that the popularization of science would simply begin with him.

Today, a second generation of science communicators like Neil deGrasse Tyson -- who was warmly courted by Sagan when choosing a college -- and Bill Nye, who took Sagan's astronomy course at Cornell, carry on his legacy of making science cool and accessible. Tyson has even starred in a reboot of the original Cosmos. Sagan is cited as an influence by everyone from famous musicians to science bloggers who were toddlers when he died. (Me, that one is me).

He just had a particular knack for inspiring an awe of the universe.

[Neil deGrasse Tyson brings science to late-night TV for the first time ever]

Here is Williams reacting to an original recording of some of the music from Cosmos:

In a recent interview with the Today Show, Williams explained that the framed photo of Sagan makes him feel grateful to be alive.

“I watched ‘Cosmos’ as a child and I was always blown away by [Sagan’s] mind and the way he thought,” Williams said. “When I look at that picture I realize how lucky we all are ... to be on this planet and be able to do what we love to do every day. Seeing Carl’s face reminds me of it.”

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