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Anybody got a decoder ring? It would probably be welcome in the quest to decipher the Voynich Manuscript, a cryptic tome that’s puzzled researchers for nearly 100 years. Filled with strange characters and weird illustrations (including Zodiac symbols and nude ladies emerging from pipes), nobody’s been able to make heads or tails of what this mysterious manuscript is even about. But thanks to the work of some Arizona-based scientists, we now at least have a better idea of when it was made.

University of Arizona physicist Greg Hodgins, who’s a chemist and archaeological scientist by training, used carbon-14 dating to determine the age of the book’s parchment pages, which are made of animal skin (and thus contain carbon 14). Turns out the Voynich Manuscript, discovered near Rome in 1912 by rare book dealer Wilfrid Voynich, was created sometime between 1404 and 1438 — about a century earlier than researchers had previously thought.

That may rule out a couple theories about the book’s origins (including one that proposes it was penned by 13th-century English friar and scientist Roger Bacon), but speculations still abound. Here are just a few:

• It’s the secret work a religious sect.
• It’s a kind of pharmacopoeia, detailing early to medieval medical practices.
• It’s a recipe for the “elixir of life.”

What do you make of the Voynich Manuscript? As long as it doesn’t predate the 15th century, your guess is as good as mine.

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