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What Can We Learn From the Solar Eclipse?


On Monday, August 21, 2017, North America will experience a total solar eclipse. For this occasion humanity will continue to take part in a nearly 5,000-year-old tradition, making a big deal out of the solar eclipse! A stroll through history lets us learn the many ways we’ve approached this celestial occasion in the past, but modern-day observers are excited to continue learning about our sun too. What can we learn from the solar eclipse? Listen to this Question Your World radio report produced by the Science Museum of Virginia to find out.

Since the dawn of humanity, we’ve been observing and learning as much as possible about the natural world around us. Initially, humans considered celestial, atmospheric, and weather anomalies to be the results of angry gods. Some of the earliest astronomy recordings date back to 5,000 years ago. The ancient Babylonians and Chinese were among the first to regularly document eclipses starting about 3,000 years ago. For some Babylonians solar eclipses even involved finding a temporary ruler to sit on the throne to avoid any harm being passed on to the real emperor. Once the eclipse passed, the temporary emperor would be given the boot and the original ruler would be put back in place. Failure to predict the total eclipse even resulted in the execution of some Chinese astrologers.

The Vikings, the natives of northwestern America, the ancient civilizations in Vietnam, and many other places around the world had their own guesses as to what was happening when an eclipse took place. Usually most of those revolved around something that we humans hold very near and dear to us, eating. The earliest Nordic civilizations thought a giant wolf was eating the sun. Some ancient Chinese astrologers saw a dragon eating the sun while native Americans thought this was a bear catching up to and taking a bite out of the sun. While eating is an awesome and necessary process, they were still off by a long shot.

About two thousand years ago, the Greeks took a different approach to the eclipse. They were the first to put it through the perspective of science. Early on, the Greeks were the first to presume that the sun had to be further away than the moon since the moon was able to get in front of the sun, clever thinking! These early scientists used shadows, sticks, and their feet to measure distances on Earth and would then use that data to figure out how the dimensions and distances of the Earth, moon, and solar system. Pretty impressive considering they were only off by a few thousand feet.

As time progressed more and more civilizations started to better understand the science behind the eclipse. When the moon blocks out most of the sun we were able to observe the corona. As the daylight turned dark, this provided an excellent opportunity to also study other stars and planets that are usually not visible in the day time because of the brightness of our sun. Even Einstein’s theory on general relativity was further supported by observing the shifts in star positions between day time and nighttime observations. The sun’s gravity was able to warp space time and thus change the apparent positions of distant stars in the sky.

While past observations have been great for allowing us to understand what we currently know, there’s still a lot of information left to be gained by studying eclipses. This year scientists, climatologists, and astronomy fans, in general, are excited to see what new information can be scored in regards to studying the corona, solar temperatures, and even studying our own climate and atmosphere. With projects like the Eclipse Mega movie observers from around the world can provide photos to help scientists observe the changes in the sun over the course of several hours from several different vantage points.

This is a pretty special event considering that a coast to coast total solar eclipse has not happened in North American in nearly a century. Scientists are urging everyone to wear proper eye protection and to participate in collecting as many photos as possible while the bright daytime sky experiences darkness for about two minutes. The internet is already in a frenzy, but on August 21st between the media and moon itself the sun will get a lot of coverage!