In 1504, Christopher Columbus, on his fourth trans-Atlantic voyage, was stranded on the shores of Jamaica, with his ships crawling with marine worms and his crew hungry. The Indigenous Arawak people, who had initially welcomed the Europeans, had grown weary of their demands.
But Columbus had a trick up his sleeve: According to The Guardian, he consulted his astronomical tables and saw that a total lunar eclipse was imminent on March 1, 1504. Summoning the island’s leaders, he warned them that his god would blot out the moon in anger if they did not help him by providing supplies. Fear gripped the Arawak people when the blood-red eclipse darkened the sky, and they rushed to appease Columbus with food and aid.
Related: Where will the ‘blood moon’ total lunar eclipse be visible in March 2025?
The 1504 total lunar eclipse
“The 1504 eclipse is well-documented as having been used by Columbus, who knew of the eclipse prediction, to convince the native tribes in Jamaica to aid his crew,” Patrick Hartigan, a professor of physics and astronomy at Rice University in Houston, wrote in a recent paper published by the American Astronomical Society.
It’s a great story, but what does it have to do with the total lunar eclipse on March 13-14? Remarkably, the eclipses are 521 years apart, which means the moon takes an almost identical path through Earth’s shadow and occurs against the same background stars.
How lunar eclipses are predicted
This striking similarity is no coincidence. All eclipses come in families called Saros. A near-identical eclipse occurs every 223 “lunations” — orbits of the moon around Earth. According to NASA, that’s once every 6,585.3 days — or 18 years, 11 days, 8 hours. The total lunar eclipse on March 13-14, 2025, is part of a pattern Saros 123 cycle, which has been producing total lunar eclipses every 18 years, 11 days, 8 hours since July 16, 1628, and will do so until April 4, 2061.
Multicentury eclipse cycles
Saros, which literally means “the repetition,” is how eclipses are predicted many centuries ahead. However, there are other cycles at play. One is the Hypersaros, a multigenerational cycle that lasts 521 years. That’s equivalent to 25 Saros cycles, and it has an observable effect. Eclipses separated by a Hypersaros have similar depths, appear very close to the same location in the sky, and occur at nearly the same time of year, according to Hartigan.
On March 13-14, skywatchers will have the same view of the “blood moon” total lunar eclipse as Columbus and the Arawak people had on Feb. 29, 1504, a celestial déjà vu that echoes across more than five centuries.