It was an opportunity too good to pass up; the ball was teed up and all it took was a solid swing. When rapper B.o.B. (Bobby Ray Simmons) recently posted 50 tweets purporting to prove that the earth is flat, he claimed to “be going up against the greatest liars in history,” a conspiracy society led by NASA. Never mind that the claim was a thinly veiled promotion for Simmons’ latest recordings, this was a juicy tidbit for astrophysicist/entrepreneur Neil deGrasse Tyson to devour. First there was Tyson’s set of short Twitter responses with clever scientific facts proving the Earth is round, followed later by his own rap response to B.o.B. along with his nephew rapper Stephen Tyson.