When you're a celebrity, the public tends to only recognize you based upon your talent or whatever you're famous for. There are plenty of celebrities out there who are smarter than they seem, as many have gone to college to get degrees, and some have even taken their education even further than that. As a result, there are a number of celebrities who have gone on to get their PhDs.

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From rocket scientists to politics and even mathematicians, you'd be surprised to find out just how smart some celebrities are. While some may show off their degrees while others might be a little quiet about it, there are still some incredibly smart celebrities out there, and you might be surprised to find out just who they are!

9 Brian May

Brian May is an incredible guitar player most known for being in the band Queen alongside Freddie Mercury. Not only did he play guitar and write songs for one of the most famous bands in the world, but he also got his Ph.D. in astrophysics. Music came first, though, since it took three decades to finally complete his degree. He was studying astrophysics before Queen was even a band, only to put his education on hold to pursue music. He picked things up again years later, writing a 48,000-word thesis called "Radial Velocities in the Zodiacal Dust Cloud." Brian May is a very intelligent man, that's for sure.

8 Greg Graffin

You might know Greg Graffin as the lead singer of the band Bad Religion. Not only is he a great musician, but he's also very smart too. Greg Graffin has a Ph.D. in zoology from Cornell University. He knows everything and anything about evolution and has even published a science memoir called Anarchy Evolution: Faith, Science and Bad Religion in a World Without God. Greg Graffin even took his expertise back to his alma mater where he taught a class about Evolution at Cornell.

7 Rachel Maddow

Rachel Maddow is a political commentator with her own very successful show on MSNBC. With so much knowledge about the political world, it's no surprise that Rachel has studied hard for her Ph.D. Rachel first got her B.A. in public policy at Stanford University. She then went on to earn her Ph.D. in politics in 2001 where she wrote her dissertation on "HIV/AIDS an Health Care Reform in British and American Prisons" since she spent quite some time as a prison AIDS advocate.

6 Miuccia Prada

Growing up, Miuccia Prada didn't always want to be involved in the fashion world. Her mother was an heiress to a luxury goods company then known as Fratelli Prada. Fashion wasn't on Miuccia's mind, though, as she originally wanted to be a politician. In fact, she has her Ph.D. in political science from the University of Milan where she has leaned toward left-wing politics and feminism.

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Things changed, however, when she got involved with the Prada family business in 1970, taking on the brand and trying to revive it. With her designs and hard work, she brought the company back to life, making it one of the biggest designer brands that we know and love today.

5 Dexter Holland

Dexter Holland of the band The Offspring is smarter than smart as he has a Ph.D. in molecular biology. Originally, he was enrolled in school before his music career took off. He decided that he wanted to put his education on hold to pursue music, and he finally went back to it years later. Even when he was touring and recording music, Dexter worked a little at a time on completing his PhD. as he conducted research and published a dissertation on the molecular dynamics of HIV and general virus/host interaction that was a whopping 175 pages long.

4 Mayim Bialik

You might know actress Mayim Bialik from The Big Bang Theory where she played Dr. Amy Farrah Fowler who is a neuroscientist. What many people might know about Mayim is she's actually a neuroscientist in real life, as she has a Ph.D. in neuroscience that she received in 2007. So no, Mayim wasn’t really acting when it came to all of the science stuff.

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When Mayim was younger, she starred in the hit show Blossom, but once the show was over, she disappeared from the acting world for a while — to follow her education dreams. That’s when she finally got her Ph.D. in neuroscience which helped a lot when she got the role of Dr. Amy. So, all of those science facts Dr. Amy was constantly saying on the show were all Mayim!

James Franco

In the acting world, we know that James Franco is a busy man. What you might not realize about James is he’s very educated. Over the years he has earned a number of degrees from UCLA, New York University, as well as Columbia University. James decided that he wanted to take his education a step further than that, as he has a Ph.D. in English from Yale University. With all of the acting projects and other things James Franco is pursuing in his career, it's hard to believe that he has all this time to study for degrees, however, we suppose when you want it bad enough and work hard enough you can make things happen.

3 Dan Grimaldi

You might remember actor Dan Grimaldi from his time on The Sopranos playing twins Philly and Patsy Parisi, however, there was a lot more to him than playing the characters on the hit HBO series. What many people might not know about Dan is the fact that he was a very intelligent man. He has a number of degrees ranging from a B.A. in mathematics from Fordham College, an M.S. in Operations research from New York University, as well as a Ph.D. in data processing from the City University of New York. That's pretty impressive for an actor!

2 Frank Ryan

Many people assume that not many athletes want to pursue a degree when they're famous professional athletes, but when it comes to Cleveland Browns quarterback Frank Ryan, he had other things in mind besides football. While he was playing the NFL, Frank was also pursuing a degree in math. He found that earning his Ph.D. in mathematics at Rice was a way for him to spend his free time wisely. As if earning a Ph.D. when he was a professional football player wasn't enough, he also was an assistant professor where he taught math at Rice as well as the Case Institute of Technology.

1 Shaquille O'Neal

Of course, Shaquille O'Neal is known as one of the best professional basketball players of all time, however, did you know that he has a Ph.D., too? In fact, Shaq has a Ph.D. in education that he received from Barry University. During his time studying for his degree, Shaq was a pretty good student as he put a lot of time and effort into his work where he had a cumulative grade-point average of 3.813. Although you wouldn't see Shaq walking around on campus, as most of his classes were online.

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