Neil deGrasse Tyson may be one of the most celebrated scientists of our time, but that doesn’t make him immune to racial profiling.

On Tuesday, Tyson posted an excerpt from his 2004 book “The Sky Is Not the Limit: Adventures of an Urban Astrophysicist” on Facebook, in which he and several colleagues at a 1991 National Society of Black Physicists conference recounted times they had been detained by police without reason. He said he had “a dozen different encounters to draw from.”

“There was the time I was stopped late at night at an underpass on an empty road in New Jersey for having changed lanes without signaling,” Tyson wrote. “He [the cop] went on to say that the ‘real reason’ why he stopped me was because my car’s license plates were much newer and shinier than the 17-year old Ford that I was driving. The officer was just making sure that neither the car nor the plates were stolen.”

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Tyson also described being stopped several times while trying to bring boxes of textbooks into his graduate school office.

“I wonder how often that scenario shows up in police training tapes,” he said. “In total, I was stopped two or three times by other security officers while entering physics buildings, but was never stopped entering the campus gym.”

When Tyson and his colleagues looked back on the incidents, they concluded the only unifying factor was that all of those telling the stories were black.

“We were guilty not of DWI (Driving While Intoxicated), but of other violations none of us knew were on the books: DWB (Driving While Black), WWB (Walking While Black), and of course, JBB (Just Being Black),” he said.

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Shortly after the conference, the Rodney King riots in 1992 occurred in South Central LA, which Tyson points out were the result of the acquittal of the police officers involved.

“Upon seeing the now-famous video of the incident, I remembered being surprised not because Rodney King was beaten by the police but because somebody finally caught such an incident on tape,” he said.