In a small, cluttered office at the University of Pennsylvania, a bespectacled scholar deciphers the writings of an ancient culture that has enthralled him for decades. This month, his work can be found in an academic journal titled Antiquity.

And oh, by the way, on the tail fin of a 747.

Heavy metal called, so Simon Martin, associate curator at Penn's Museum of Archaeology and Anthropology, obligingly answered.

The veteran rockers of Iron Maiden chose an ancient Maya theme for their latest album, The Book of Souls, and Martin, 54, is the man to see on that subject. The group enlisted him to translate its 11 song titles into hieroglyphs, the elaborate symbols used by the Central American people centuries ago.

The translations were reproduced in the album booklet, and two of them also were painted on the tail fin of the band's tour plane.

Because, why not?

Appropriation of cultural and supernatural themes is as intrinsic to the genre as scorching solos on a Stratocaster (see the Norse mythology in Led Zeppelin's "Immigrant Song," or the immortal ode to Stonehenge in the heavy-metal send-up Spinal Tap).

A sample from the title track on Book of Souls:

They were praying to the gods of nature

And were living in the cities of stone

Towers reaching upward to the heavens

Sacred wonders for the world unknown.

Catchy stuff. Translating the titles into the ancient Maya tongue, however, was not easy, even for someone whose passion for the culture began in childhood.

At age 11, when Martin lived in London, he saw a BBC program about the people who held sway over what are today Guatemala, Belize, and southeastern Mexico, and was captivated.

He taught himself everything he could about the civilization, which reached its greatest heights in the years 250 to 900. He went on to pursue a career as a graphic designer, his interest in the Maya remaining a hobby until the mid-1990s, when he began to study the subject full time. Martin attended conferences, visited archaeological sites, and published papers that drew acclaim in the field. He came to Penn in 2003.

The contact from Iron Maiden came in late 2014, via email.

Before that, the band had somehow found its way to Yale University's Mary Miller, who studies the art of the Maya. She is not a hieroglyph expert, and she suggested Martin instead.

Martin happened to be in London at the time, and went to meet the band's representatives. No meeting the musicians, however.

"I'm afraid there was no hanging out with the long-haired guys," he said.

The translation work took him several days. He declined to comment when asked what he was paid.

It was a multistep process, as there is no English-Maya dictionary. Instead, he began by translating the song titles into Spanish.

Then he turned to a compendium of dictionaries, some of them written by Spanish clerics in the late 1500s, which provided translations into a Mayan tongue known today as Yucatec. The Spaniards rendered that language phonetically using the Roman alphabet.

But the dictionary did not contain all the words he needed, so in some cases Martin had to settle for loose equivalents. (The song title "If Eternity Should Fail," for example, was a bit of a challenge.)

From there, Martin drew on his own expertise to spell out the Yucatec translations with hieroglyphs. Some, like the word for cloud, had a direct symbolic equivalent. Others had to be formed with a combination of symbols, each representing the sound of a different syllable.

The linguistic handiwork was reproduced in a booklet accompanying the album, which was released in September 2015. The band's tour began in February, but Martin did not learn until recently that hieroglyphs representing two of the songs - "If Eternity Should Fail" and "Speed of Light" - had been painted on the fin of the jet.

Band members, newly arrived in Tokyo for their latest tour stop, were not immediately available for comment on Martin's efforts.

The scholar said he did not know exactly why the band chose a Maya theme, but welcomed the opportunity to bring new exposure to the proud civilization, especially after the Maya's last moment in the public eye was the source of some confusion.

December 2012 marked the end of a cycle in the Maya calendar that had lasted more than 5,000 years, and the milestone was popularly interpreted to mean that the ancients had forecast the end of the world. Nope, just the end of a cycle, Martin said.

For the Iron Maiden translation project, he praised the band for wanting to get it right.

"The key thing is, they wanted things to be authentic," he said. "I wanted to give it my best shot and keep the Maya in the public eye."

So far, the tour has included three stops in Mexico, where many descendants of the Maya still live. A March 4 show in Mexico City drew more than 20,000 fans.

In an appreciative write-up about the show in the Mexico City newspaper Reforma, which is published in Spanish, the writer used the untranslated word headbanging.

Apparently, some things are best left in English.