These days, more than 30 percent of Americans sport tattoos—but there’s nothing new about our fascination with body art. As tattoos take over contemporary culture, scientists are looking to the past and uncovering the secrets of centuries-old ink.

Lasers are typically used to remove tattoos from the skin with mixed results. These tight beams of light can also reveal the ink that once decorated 1,200-year-old pieces of mummified skin. Using a newly developed laser technique,