A total solar eclipse will march across the United States on Monday, casting a shadow from Oregon's Pacific Coast, across the U.S. heartland, all the way to South Carolina's Atlantic Coast.
Why is this eclipse so anticipated?
This will be the first time in 38 years that the mainland United States will experience a total eclipse, and it will be the first time in 99 years that a total eclipse will pass from the U.S. Pacific Coast to the U.S. Atlantic Coast. The last time that happened was in 1918, traveling from Washington state to Florida.
Hawaii experienced a total solar eclipse in 1991.
Total eclipses happen every one to three years somewhere in the world, however, they are most likely to take place over the ocean since most of the Earth is covered by water.
What is an eclipse?
A total eclipse happens when the moon passes between the Earth and the sun and completely blots out the sun's light, except for the corona of its outer atmosphere.
From Earth, the moon will appear to be the same size as the sun. This is possible because while the moon is 400 times smaller than the sun in diameter, it is also 400 times closer to Earth than the sun. When the two line up exactly, the skies go dark.
Where can I see the eclipse?
The path of totality, where the moon's shadow will completely cover the sun, is a diagonal band that cuts across the country, about 100 kilometers wide. Those outside that narrow band can still see a partial eclipse, extending up to Canada and down to the top of South America.
Totality will begin near Lincoln City, Oregon, cross the states of Idaho, Montana, Wyoming, Nebraska, Iowa, Kansas, Missouri, Illinois, Kentucky, Tennessee, Georgia, North Carolina and finally South Carolina.
The biggest cities in the path include Nashville, Tennessee; Charleston, South Carolina; and Salem, Oregon.
How long will it last?
The total eclipse will last longest near Carbondale, Illinois: 2 minutes and 44 seconds.
The first city to enter the totality will be Lincoln Beach, Oregon, at 10:16 a.m. Pacific time and last to exit the totality is Charleston, South Carolina, at 2:48 p.m. Eastern time.
How can I watch it?
About 12 million people are estimated to live in the path of totality while tens of thousands of others are planning to travel to witness the event, many to remote parks and rangelands across the U.S. heartland.
To avoid eye damage, experts say everyone should wear special solar glasses. Many cities have seen long lines of people waiting to pick up protective eye glasses and the price for such glasses have spiked online.
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What about the weather?
Heavy clouds will hide the most dramatic effects of the eclipse, causing travelers to carefully plan where to go to find the best visibility. The forecast looks best in the Western U.S., while South Carolina is the one place in the totality most likely to see clouds. Some travelers are preparing several options in the hopes of finding clear skies, although officials say there could also be gridlocked roads as the eclipse approaches and tourists chase blue skies.
When is the next one?
The next total solar eclipse to touch the U.S. won't be for another seven years. In 2024, a line of totality will cross from Texas, up through the Midwest, and then over to New York, New England and New Brunswick, Canada.
Outside of the United States, the next eclipse will occur in 2019 and will be viewable from the South Pacific, Chile, and Argentina.