Bob Datta's tattoo of his wife's initials, EEE, encoded into an image of DNA. The code for the protein glutamate is “E.” Depending on how you read Datta's tattoo, it either says “Eliza Emond Edelsberg” or “glutatmate-glutamate-glutamate.” Datta is a neurobiologist at Harvard Medical School and a longtime friend of Carl Zimmer. His tattoo inspired Zimmer’s book Science Ink.

Melissa Schumacher’s tattoo of Cantor’s theorem written in Frege’s notation. Schumacher, a third-year grad student at MIT says, "When I look down on my arm, [there are] two lines of symbols, if I turn it over there’s a heart. What my tattoo says is if Cantor’s theorem, then love. It’s a necessary truth for me."

The flip side of Schumacher’s tattoo.

Daniel Schmoller’s tattoo of an adenosine triphosphate (ATP) molecule. One of the most biologically important molecules, ATP transports and stores chemical energy within cells. Schmoller is a pre-med student at the University of Wisconsin.

A tattoo of the skeleton of a Rana pipiens (northern leopard frog) on David Laurice, a grade school science teacher.

Milad Khongar’s tattoo of the numerical value of the golden ratio.

A tattoo of the full moon as seen from earth. The tattoo signifies the night this scientist's parents met — July 20th, 1969 — the night of the Apollo 11 moon landing.