Fresh off of dominating the headlines with his "the Earth is flat" talk, B.o.B drops the video for his The Water EP cut "Blank Mafia." Dressed in all black, B.o.B is militant as he raps about boycotting authority and putting the power back in the people's hands. With his crew backing him, the 2009 XXL Freshman makes sure you're focusing on his lyrics instead of diluting his vision with glitz and glamor. Wearing a "Silent Weapons Quiet Wars" hoodie, B.o.B stands up as a voice more concerned with people's rights than their codeine consumption.

In late January, the rapper became the talk of social media when he posted a number of photos and tweets that backed up his belief that the Earth is flat. "No matter how high in elevation you are...the horizon is always an eye level...sorry cadets..I don't wanna believe it either," he tweeted. "Don't believe what I say, research what I say."

Once B.o.B's tweets started to make the rounds and landed on non-hip-hop websites like BuzzFeed, astrophysicist Neil deGrasse Tyson chimed in and went toe-to-toe with the rapper. In an interview with XXL, Tyson explained how he caught wind of the MC's claims and why he chose to school him on astrophysics.

"I heard of B.o.B. I’m not into him ’cause they’re so many great musicians out there. And so I looked him up and reminded myself of some of his more popular ones that hit a couple years ago," said Tyson. "And then I said, 'Holy shit! He‘s got 2.3 million Twitter followers so all this flat earth stuff is going to a boatload of people.'  If this didn’t come across my threshold I would’ve just said let it be. This is the internet, it’s a free country, you can think what you want. And then I looked at what he was saying on his tweets. He was saying I’m applying physics and math to solve this and here’s why the earth is flat. And I said, “Oh, now you crossed a line there, buddy.”

The beef spilled over from the internet to wax as B.o.B dropped "Flatline." Not taking the diss lightly, deGrasse Tyson's nephew fired back with "Flat to Fact."

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