Today, we can predict exactly when eclipses will happen, and many people look forward to them. However, in ancient times, eclipses were quite frightening because people didn’t understand them.
Hi, I’m Cameron, and this is MinuteEarth. Thousands of years ago, when the sun suddenly disappeared from the sky during an eclipse, it was a scary event for people. In fact, the Chinese word for eclipse means “to eat,” as if a dragon was devouring the Sun.
It’s no wonder that ancient civilizations tried to explain eclipses and figure out when they would happen again. About 5,000 years ago, people in what is now England built Stonehenge, a monument made of huge stones. If you stand in the center of Stonehenge, the sun rises behind a specific stone on the summer solstice, suggesting it was used for watching the sky. There are also 56 holes around Stonehenge that might have been used to track the Sun and Moon, possibly helping to predict lunar eclipses. However, since the builders left no instructions, scientists still have many questions about their purpose.
Around 4,000 years ago, Chinese astronomers made the first known record of an eclipse, starting a long history of about 920 solar eclipse accounts in China. Unfortunately, many early descriptions were too vague for modern astronomers to pinpoint their exact timing. The earliest confirmed eclipse was recorded on a 3,300-year-old clay tablet, describing a total solar eclipse seen in Ugarit, present-day Syria, in 1223 BCE.
Nearly 600 years later, Babylonian astronomers began to notice patterns in eclipses. They found lunar eclipses—when the full moon turns red as it enters Earth’s shadow—particularly important, as they were seen as bad omens for their kings. By studying these events, they discovered that lunar eclipses repeat in a cycle of 18 years, 11 days, and 8 hours, known as the saros cycle. This pattern also applies to solar eclipses. If a solar eclipse happens in one place, another similar eclipse will occur 18 years, 11 days, and 8 hours later, but shifted westward due to Earth’s rotation.
For example, similar paths of solar eclipses repeat over the 20th and 21st centuries. Both solar and lunar eclipses happen more often than every 18 years because up to 40 different sets of eclipses can overlap at any time.
Today, we can calculate when and where every eclipse has occurred over the last 4,000 years and predict them far into the future. For instance, a solar eclipse will occur on September 7, 2974, at 12:51 PM local time, passing directly over Stonehenge. If you live in North America, you have two upcoming chances to see an eclipse: an Annular Solar Eclipse on Saturday, October 14, 2023, and a Total Solar Eclipse on Monday, April 8, 2024. Both will have paths across the US, Canada, and Mexico, and we are very excited about them.
We have teamed up with NASA’s Heliophysics Education Activation Team to create videos exploring the science and wonder of solar eclipses. NASA HEAT provides educational resources for learners of all ages to better understand our Sun and its effects on Earth and the Solar System, bringing NASA’s work into classrooms and platforms like YouTube to inspire future scientists.
Using simple materials like a flashlight, a globe, and a small ball, create a model to demonstrate how solar and lunar eclipses occur. Experiment with the positions of the Earth, Moon, and Sun to see how shadows are cast and how eclipses happen. This hands-on activity will help you visualize the celestial mechanics behind eclipses.
Choose an ancient civilization and research how they interpreted eclipses. Create a short presentation or skit to share with the class. This will help you understand the cultural significance of eclipses and how different societies explained these mysterious events.
Use online resources to track the saros cycle of eclipses. Identify when and where the next few eclipses in a particular cycle will occur. This activity will help you understand the predictability of eclipses and the patterns that ancient astronomers discovered.
Research Stonehenge and its possible use as an ancient astronomical observatory. Create a poster or digital presentation that explains how Stonehenge might have been used to predict eclipses and other celestial events. This will give you insight into the ingenuity of ancient peoples in understanding the sky.
Watch videos created by NASA’s Heliophysics Education Activation Team about solar eclipses. Take notes on the scientific explanations and the wonder of these events. Discuss with your classmates what you learned and how modern technology helps us understand eclipses better today.
Here’s a sanitized version of the YouTube transcript:
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These days, we know exactly when eclipses are going to happen, and we even look forward to them. However, humans didn’t learn to predict eclipses because they were exciting; long ago, eclipses were quite alarming.
Hi, I’m Cameron, and this is MinuteEarth. For people living thousands of years ago, the sudden disappearance of the sun from the sky was a distressing experience. In fact, the Chinese word for eclipse literally means “to eat,” as in, the Sun is being consumed by a dragon.
It’s no surprise that ancient civilizations developed various explanations for both solar and lunar eclipses and sought to understand when they might occur again. About 5,000 years ago, people in what is now England transported about a hundred massive stones to construct a structure known as Stonehenge. This monument consists of an inner ring of large stones and an outer ring of smaller stones. If you stand in the center of the rings, the sun appears to rise behind a specific stone on the summer solstice, indicating that Stonehenge was built for astronomical observations. There is also a ring of 56 post-holes surrounding the monument that could have been used to track the positions of the Sun and Moon, potentially allowing the builders to monitor lunar eclipses. However, since the builders did not leave behind any instructions, scientists still have many questions about their intentions.
Around 4,000 years ago, Chinese astronomers made the earliest known mention of an eclipse, marking the beginning of approximately 920 solar eclipse accounts throughout Chinese history. Unfortunately, many of the early descriptions were too vague for modern astronomers to determine their exact timing. The earliest verifiable eclipse sighting was recorded on a 3,300-year-old clay tablet, describing a total solar eclipse observed in the city of Ugarit, in present-day Syria, in 1223 BCE.
Nearly 600 years later, in Babylon, astronomers began to understand the patterns of eclipses. Lunar eclipses—when a full moon completely enters the Earth’s shadow and appears red—were particularly significant to the Babylonians, who viewed them as ominous signs for their kings. They discovered that lunar eclipses were key to identifying eclipse patterns. When the moon passes into the Earth’s shadow, the event is visible from the entire nighttime half of the planet. In contrast, solar eclipses can only be seen from within the moon’s shadow. As a result, Babylonian astronomers observed roughly half of the lunar eclipses but only a few solar eclipses.
This data allowed them to determine that lunar eclipses tend to repeat every 18 years, 11 days, and 8 hours—a cycle known as the saros. Interestingly, this pattern also applies to solar eclipses. If a solar eclipse occurs in one location, another with a similar path will be visible 18 years, 11 days, and 8 hours later. However, due to the additional 8 hours, the Earth will have rotated 120 degrees further, shifting the eclipse path westward. This pattern continues for subsequent eclipses.
For example, there are similar paths of repeating solar eclipses during the 20th and 21st centuries. Both solar and lunar eclipses occur more frequently than every 18 years because up to 40 different sets of identical eclipses can overlap at any given time.
Today, we can calculate the timing and path of every eclipse that has occurred over the last 4,000 years and accurately predict them far into the future. For instance, a solar eclipse will take place on September 7, 2974, at 12:51 PM local time, passing directly over Stonehenge. If you live in North America, there are two upcoming opportunities to see an eclipse: an Annular Solar Eclipse on Saturday, October 14, 2023, and a Total Solar Eclipse on Monday, April 8, 2024. Both will have extensive paths across the US, Canada, and Mexico, and we are very excited for them. We have collaborated with NASA’s Heliophysics Education Activation Team to create videos exploring the science and wonder of solar eclipses. NASA HEAT aims to provide educational resources for learners of all ages to enhance their understanding of our Sun and its effects on Earth and the Solar System, bringing NASA’s work into classrooms and platforms like YouTube to inspire future scientists.
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This version maintains the original content while removing any informal language and ensuring clarity.
Eclipses – An event where one celestial body moves into the shadow of another celestial body, blocking its light. – During solar eclipses, the moon passes between the Earth and the sun, casting a shadow on Earth.
Ancient – Belonging to the very distant past and no longer in existence. – Ancient civilizations, like the Babylonians, made significant contributions to early astronomy.
Sun – The star at the center of our solar system that provides light and heat to the planets. – The sun is crucial for life on Earth, and its position in the sky changes with the seasons.
Moon – The natural satellite that orbits the Earth, reflecting light from the sun. – The phases of the moon have been used to track time since ancient times.
Stonehenge – A prehistoric monument in England, believed to have been used for astronomical observations. – Some historians think that Stonehenge was used to predict solar and lunar eclipses.
China – A country in East Asia with a rich history of astronomical observations and discoveries. – Ancient China was one of the first civilizations to record solar eclipses.
Babylonian – Relating to Babylon, an ancient city known for its early advancements in astronomy. – Babylonian astronomers were among the first to recognize patterns in the movements of celestial bodies.
Patterns – Repeated or recurring sequences or designs, often used to predict future events. – Astronomers study patterns in the stars to understand the universe better.
Solar – Relating to or determined by the sun. – Solar energy is harnessed from the sun’s rays and is a renewable resource.
Lunar – Relating to or determined by the moon. – A lunar eclipse occurs when the Earth comes between the sun and the moon, casting a shadow on the moon.
