Long before eclipses became a subject of modern astronomy, they were recorded in rock carvings, ancient manuscripts and religious texts. Across thousands of years, humans have watched the Sun and Moon disappear from the sky and tried to understand what these rare events meant.
According to a blog post in NASA's website, one of the earliest possible records of an eclipse dates to November 30, 3340 B.C.E. at the Loughcrew Megalithic Monument in County Meath, Ireland. Archaeologists discovered spiral-shaped and circular petroglyphs carved into the rocks. In front of one carving showing overlapping concentric circles, they also found the charred remains of nearly 50 individuals. Researchers continue to debate what the carvings represented and whether they were connected to an eclipse.
Ancient Chinese records called it a “eaten” Sun
By around 1200 B.C.E. , Chinese scribes in Anyang were documenting eclipses on oxen shoulder blades and tortoise shells known as oracle bones.
Their description was strikingly simple: “The Sun has been eaten.”
Thousands of years later, astronomers at NASA’s Jet Propulsion Laboratory used some of these ancient records to investigate how Earth's rotation has changed. By determining when the eclipses occurred and where the Moon's shadow would have fallen, scientists were able to compare Earth's ancient rotation with its modern rate.
Records of eclipses from 1226, 1198, 1172, 1163 and 1161 B.C.E. helped researchers conclude that Earth’s rotation had slowed by about 47-thousandths of a second per day over roughly 3,200 years .
Eclipses also appear in religious history
Ancient observations of eclipses were not limited to scientific records. They also appear in religious traditions.
Christian texts describe the Moon turning to blood following the crucifixion of Jesus. Some scholars have linked this description to a lunar eclipse and used astronomical calculations to investigate possible dates for the crucifixion, including April 3, 33 C.E.
The Quran also contains references to solar eclipses, including one associated with the period before the birth of Mohammed and another on the day his son Ibrahim died.
The Maya used eclipses to understand the sky
The Maya developed sophisticated systems for tracking astronomical events. Their observations were recorded through hieroglyphs carved into stone, painted on pottery and murals, and written in bark-paper codices.
Maya astronomers recorded eclipses and were able to predict them. Researchers Harvey and Victoria Bricker demonstrated that the Maya astronomical records included a prediction of the July 1991 solar eclipse .
Astronomical knowledge also became part of calendars, agricultural practices and ceremonial traditions, some of which continue through oral traditions among Maya communities in Mesoamerica.
A mysterious eclipse carving in New Mexico
Eclipse observations can also be found in the archaeological record of North America.
At Chaco Canyon in New Mexico , a petroglyph created by early Pueblo people may represent a solar eclipse that occurred on July 11, 1097 . The carving includes a swirling loop extending from the central shape.
Some researchers have suggested that the feature could represent a coronal mass ejection , a powerful eruption of material from the Sun. Modern scientists study such solar eruptions using spacecraft, giving today's researchers a very different set of tools to investigate phenomena that ancient observers could only watch from Earth.
The 1919 eclipse helped prove Einstein right
Eclipses eventually became central to one of the biggest scientific breakthroughs of the 20th century.
Albert Einstein proposed his theory of general relativity in 1916 , arguing that massive objects can warp spacetime and bend the path of light.
The crucial test came during the May 29, 1919 solar eclipse . British astronomer Sir Arthur Eddington led an expedition to observe stars near the Sun during the eclipse. Because the Sun's glare was blocked, researchers could photograph stars that appeared close to it in the sky.
The positions of those stars appeared shifted, providing evidence consistent with Einstein's prediction that gravity could bend light.
The eclipse helped transform general relativity from a bold theoretical idea into one of the most famous scientific theories in history — and propelled Einstein to international fame.
From mysterious carvings in ancient Ireland to oracle bones in China and a scientific expedition in 1919, eclipses have repeatedly done more than darken the sky. They have served as records of human curiosity, helped scientists measure changes in Earth's rotation and even provided a way to test our understanding of the universe.
