Argonne National Laboratory Senior Physicist Robert Smither has irons in many different fires.

"I get into astrophysics, I get into biology, I’ve actually worked with America’s Cup team to make their boat go faster," he says.

He's also an expert in "crystal diffraction," a precision x-ray process which filters neutron radiation through a lens to help create an image, just like a camera. The technique has given the human eye a new perspective on distant star systems, radioactivity hotpots around the world and cancerous tumors in the human body.

But now Smither has joined a research team that is trying to shed light on one of the art world’s oldest mysteries.

In 1505, Italian artist Leonardo da Vinci reportedly produced a large painting, known as the “Battle of Anghiari,” on a wall in Florence’s Palazzo Vecchio. But to the naked eye, no such artwork can be seen there. The location of the mural, which depicts four horsemen in battle, has perplexed art lovers for more than five-hundred years.

Those still searching for the lost masterpiece looked to Smithers: Could his 21st-century technology help solve the puzzle?

"'Can you look through a brick wall?'[they asked], and I said 'yes.'"

Researchers believe a late-16th century brick wall constructed by the artist Vasari, who painted the frescoes now visible in halls of Palazzo Vecchio, stands in front of the lost mural.

To find out, an international research team first used traditional methods.

"They made a hole in the fresco, and they thought they saw some paint, and then they made a bigger hole," says Smither. "The Italian government has been very hesitant to let people start putting more holes in different places, so that’s why we’ve been asked to try to do this without touching the wall."

According to Terry Garcia, executive vice president of Mission Programs for the National Geographic Society, which supports conservation efforts, the holes produced evidence of organic materials consistent with paint used by da Vinci, leading researchers to believe the lost mural is there.

"All of the work, all of the holes that were put into the mural, were either in areas that had been previously restored or fissures, so the original Vasari was not touched," says Garcia.

And now one big question is pressing: Even if Smither can safely determine the mural is there, would da Vinci's "Battle of Anghiari" ever see light of day without damaging the Vasari fresco standing in front of it?

Smither says it will take time and money to do it properly.

“This is a long time ago -- 1505, 1565 when it was covered up -- [so] we don’t know what shape it’s in," he says.

Either way, he hopes his crystal diffraction method will be able to peek behind the masterpiece and penetrate a mystery that has confounded art historians for centuries.