On Aug. 21, the sky darkened, the temperature dropped and all 50 United States were able to see the moon pass — at least partially — in front of the sun. It’s a solar eclipse!
A solar eclipse happens when the moon passes between the sun and Earth, casting its shadow on Earth. Sometimes the moon only covers up part of the sun. That is called a partial solar eclipse. When the moon covers up the sun completely, it’s called a total solar eclipse. As our planet rotates, the moon’s shadow moves across Earth’s surface. The path of the inner part of this shadow, where the moon totally covers the Sun, is called the path of totality.
NASA scientists used this eclipse to study our sun. During a total solar eclipse, we can see the sun’s atmosphere, called the corona. Usually the sun is so bright that we can’t see the corona. However, when the moon blocks out most of the sun’s light, we can get a glimpse of the corona.
The surface of the sun is about 10,000 degrees Fahrenheit, but the corona is much hotter. It’s about 2 million degrees Fahrenheit. The eclipse gives NASA researchers the chance to learn more about why the corona is so hot. In fact, while the eclipse only lasted about two to three minutes in one place, scientists have found a way to have more time to study it.
NASA used two research jets to chase the eclipse as it crossed the country. The jets flew very high and spent seven minutes in the shadow of the moon. Researchers used jets to help look for small explosions called nanoflares on the sun. These nanoflares may help to explain the corona’s extreme heat.
The eclipse was a fun reminder of our place in the solar system, and how much we still have to learn.
This article is provided by NASA Space Place.
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