On May 20, our moon will pass between the Earth and the sun, creating a brilliant annular solar eclipse for some viewers and an equally amazing partial solar eclipse for many others.
An annular solar eclipse happens when the moon is at a certain distance from the Earth, so that it appears relatively smaller than the sun; in a total eclipse, the moon appears to be the same size as the sun. This all happens because the moon’s orbit around the Earth isn’t a perfect circle but rather is an ellipse, putting it sometimes a bit further from the Earth than others.
An annular eclipse gets its name due to the ring, or annulus, that forms around the moon when the eclipse reaches maximum.
Due to the size of the moon compared to the size of the sun (and the fact that the moon can’t block the sunlight for everyone on Earth at once), not everyone will be able to see this annular eclipse. Only a relatively small number of people will be in just the right spot to see the annulus. But if you’re outside of the ideal viewing area, by no means are you out of luck! [...]
Some of the major cities and places that lie along the path of best viewing for this annular eclipse include Tokyo; Alaska’s Aleutian Islands; Redding, California; central Nevada; southern Utah; northern Arizona; and Albuquerque, New Mexico.
If you live anywhere in the western or midwestern United States or Canada, you’ll be able to see a partial eclipse. If you live in East Asia and near the Pacific Ocean, you’ll also be able to see the partial eclipse. Unfortunately, if you’re on the east coast of the United States, the sun will have already set by the time the eclipse starts.
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