Astrophysicist Neil deGrasse Tyson slammed rapper B.o.B's "flat Earth" theory in an epic mic drop Wednesday on Larry Wilmore's "The Nightly Show."

The segment culminated a bizarre week-long Twitter feud between Tyson and the hip-hop artist, who believes the Earth is flat.

NDT fired back on Twitter and released a diss track called "Flat to Fact."

On "The Nightly Show," Tyson told Wilmore and his guests: The “world isn’t fucking flat.” He went on to explain that "flat Earth" theories are part of a larger political problem:

In a free society, you can and should think whatever you want. If you want to think the Earth is flat, go right ahead. But if you think the Earth is flat, and you have influence over others, as would successful rappers or even presidential candidates, then being wrong becomes being harmful to the health, the wealth, and the security of our citizenry.

You may remember the "flat Earth theory" from another recent Twitter outburst, in this case from reality television and Myspace star Tila Tequila.

Like B.o.b, she cited the Manhattan skyline as evidence.

As Tyson said, it is dangerous for celebrities to trumpet anti-intellectual junk science to large social media followings. Tequila has around 46,000 followers; B.o.B's tweets go out 2.3 million.

"There’s a growing anti-intellectual strain that is growing in this country," the physicist said. "It may be the beginning of the end of our informed democracy."

As of Tuesday, the Atlanta rapper had refused to budge on his flat Earth position: