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  • Every location on Earth has been in the  shadow of at least one total eclipse,  

  • but some places experience way more of these  events than others. Like, someone who lives  

  • North of the equator is about twice as likely  to see a total eclipse as someone south of  

  • the equator. Why on Earth would that be? Hi, I'm Cameron, and this is MinuteEarth

  • This disparity in total eclipses can only happen  because of a celestial coincidence; although the  

  • Sun is 400 times bigger than the Moon, it's  also 400 times farther away from us. So,  

  • as a resultfrom here on Earththe Sun and the  moon appear to be almost exactly the same size

  • I sayalmostbecause the Earth's orbit around  the Sun is not perfectly circular. During some  

  • parts of the year, the Earth is a little farther  away from the Sunso the sun appears slightly  

  • smaller than usual. During these times, when the  Earth, moon and sun line up, it's easier for the  

  • moon to effectively block the sun, causingtotal eclipse. But other times of the year,  

  • the Earth is closer to the Sun, so the sun  appears larger than normal. When the Earth,  

  • moon, and sun line up during these times of the  year, the Sun appears larger and the moon might  

  • not totally block it, creating an annular  eclipse, which is when the moon turns the  

  • sun into a bright ring of fire in the sky. And here's where the North-South divide fits  

  • in. In either hemisphere, eclipses are more  likely in the summer, when the sun spends  

  • more time above the horizon, since it has to  be daytime in order to see a solar eclipse

  • And it just so happens that summer in  the Northern hemisphere happens at the  

  • farthest-out point of Earth's orbit, while  Summer in the Southern hemisphere happens at  

  • the closest point. As a result, total eclipses  are more likely to happen North of the equator

  • for any given spot in the Northern  hemisphere, a total eclipse happens,  

  • on average, once every 330 years. In the Southern  hemisphere, it's more like every 550 years

  • But even within the Northern hemisphere, total  eclipses become more frequent with higher  

  • latitudes. There are a few different reasons why  this might be. For one, at the highest latitudes,  

  • the summer sun rarely dips below the horizonmeaning that there is sunlight even at nighttime,  

  • as opposed to lower latitudes where nighttime  is dark during the summer. Then there's the  

  • curvature of the Earth, which causes the  moon's shadow to fall at a shallower angle  

  • at higher latitudes; eclipse paths near the  Arctic circle can be more than four times  

  • wider than eclipses at lower latitudes. So statistically, the best place to see  

  • a total eclipse is around 80 degrees north; any  given place along this line sees a total eclipse  

  • every 238 years on average. But rememberall these numbers are averages taken over  

  • a long period of time. Carbondale, Illinois  – which sits at 38 degrees North latitude,  

  • which should see a total eclipse every 330  years on averagesaw it's most recent  

  • total eclipse in 2017, yet will get its next  one in 2024. And Christchurch, New Zealand,  

  • which should get a total eclipse once every  420 yearssaw its most recent total eclipse  

  • nearly two thousand years ago, and will have to  wait another four centuries for its next one. So  

  • when it comes to seeing a total eclipse, it's not  just about latitudeit's also a matter of luck.

  • If you live in North America, there's a great  chance to have that experience soon. There's a  

  • total solar eclipse on Monday April 8th, which  will take a long sweeping path through Canada,  

  • the US and Mexico. We're super excited  about it, and we've teamed up with NASA's  

  • Heliophysics Education Activation Team  to make videos like this to explore the  

  • science and wonder of solar eclipses. NASA HEAT's mission is to provide  

  • educational guidance for learners of all ages  to deepen their understanding of our sun and  

  • its effects on Earth and the solar system  in an effort to bring NASA out of the lab  

  • and into learning spaces like classrooms and  even YouTube to inspire future scientists.

Every location on Earth has been in the  shadow of at least one total eclipse,  

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Why does the north get more total eclipses?

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    VoiceTube staff 發佈於 2024 年 03 月 28 日
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