Is there anything the amazing Mayans of pre-Colombian Mesoamerica didn’t do? If you’re keeping score, you may want to check ‘predict meteor showers’ off of your list. A new study found that hieroglyphic records from the Mayan Classic Period (250–909 CE) show important historic events occurring within days of Eta Aquariids meteor showers, indicating leaders knew about them before they happened and possibly used the events as omens or celestial signs of endorsement.

The Eta Aquariids meteor shower occurs annually between April 21 and May 20, peaking around May 6. The name comes from the constellation they appear in, Aquarius, and the star they appear to pass by, Eta Aquarii. It was officially ‘discovered’ in 1870 by Lieutenant-Colonel G. L. Tupman. They were later linked to Halley’s Comet because they occur when the Earth passes through debris on one side of its orbit. (The Leonids shower occurs when Earth passes through the other side.) It has since been determined that the debris separated from Halley’s comet hundreds of years ago and the comet itself is no longer a source of meteor showers.

That’s what we know in 2017. In a paper published in the current issue of Planetary and Space Science and reported on in Earth & Space Science News, astronomer David Asher at Armagh Observatory in Northern Ireland teamed up with Hutch Kinsman, an independent scholar of Mayan history and hieroglyphics, to determine if the ancient Mayans, who were already well-known and respected for their astronomical records, especially on Venus and eclipses, knew something about meteors centuries ago, despite the fact that there were no known Mayan records of their observance. They chose the Eta Aquariids because they should have appeared regularly during the Mayan Classic Period.

Asher and Kinsman suspected that actual Mayan records of the Eta Aquariids were lost, so they looked for other indications. Modeling their historical occurrences, Asher found 18 periods when the Eta Aquariids should have been visible to the Mayans between 250–909 CE. Kinsman then searched Mayan history during those 18 30-day periods for major events.

Kinsman’s findings were astonishing. Six of the Eta Aquariid showers occurred within four days of a ruler taking power. Others coincided with the start of wars. The most significant was the 531 CE Eta Aquariid – four days later, K’an I became king of Caracol. To confirm the validity of the model, Asher matched the meteors to Chinese records which also mentioned them during the same time periods.

The statistical matches seem to indicate the Mayans knew about the meteors. Did they – specifically their leaders, scientists and astronomers – predict the appearances of Eta Aquariids and use them to their advantage to manipulate the masses? That remains to be determined. While Kinsman peruses the hieroglyphics again for signs, Asher is plotting occurrences of the Orionids and Perseids meteor showers during the Mayan Classical Period for future studies.

What will they find? Based on past experiences, don’t bet against the Mayans.