By Tessa Trudeau
Updated Aug 18, 2017 @ 12:00 pm
Eclipse 101
Credit: Igor Zhuravlov/Getty

Unless you've been living under a rock, you're aware that there's this little event happening on this coming Monday, Aug. 21. For the first time since 1979, the contiguous United States will be treated to a total solar eclipse, aka The Great American Solar Eclipse, and it's kiiind of a big deal. It's been even longer since we've had a total eclipse that spans from coast to coast, which last occurred all the way back in 1918, so people are very excited for this phenomenon.

There's a ton of information out there (the amount of websites that have popped up dedicated to the eclipse is insane), so to make things a bit less confusing for you, we did some research through the interwebs and compiled the most important things to know. Read below for a crash course in Total Solar Eclipse 101.

VIDEO: Perfect Spots for Watching the Total Solar Eclipse Crossing the U.S.

What Is It?

According to NASA's official site dedicated to the eclipse,, a total solar eclipse is a natural phenomenon that occurs when "the moon will completely cover the sun and the sun's tenuous atmosphere—the corona—can be seen." This happens because the moon moves in between the earth and the sun, therefore blocking the sun for a period of time, except for the glowing halo of the corona.

Where Can It Be Seen?

One term you may have heard is the "path of totality," which refers to the stretch of land where the total eclipse will be visible. It will take place on a diagonal path from Oregon to South Carolina, passing through Idaho, Wyoming, Nebraska, Kansas, Missouri, Illinois, Kentucky, Tennessee, Georgia, and North Carolina.

The path will only be around 70 miles wide, give or take, so not every city or area of these states will experience the phenomenon. Anyone outside of that will only be able to see a partial eclipse, so millions of people are traveling in order to see the full thing (Oregon alone is expecting an influx of one million people). So, if you live in a place where you can see the total eclipse, consider yourself #blessed. Check out the full path here on an interactive, zoomable map.

Is It Safe To Look At?

According to NASA, "the only safe way to look directly at the uneclipsed or partially eclipsed sun is through special-purpose solar filters, such as 'eclipse glasses' or hand-held solar viewers." And no, regular sunglasses are not safe, so don't even think about it. If you are within the path of totality, you can look directly at the eclipse only while the moon is fully covering the sun—when the sky becomes dark. As soon as it starts to brighten again, pur your lenses back on. If you are outside of the path of totality, at no point should you look directly at the eclipse without solar lenses.

How Long Will It Last?

It depends where you are. Due to some sciencey stuff that we don't understand, the eclipse won't be visible for the same length of time in each location within the path of totality. This nifty grid will tell you how long you can see it in each city.

When Is The Next One?

The next total solar eclipse we will experience in the contiguous United States is April 8, 2024, but it will be visible only from Texas to Maine. This one is extra special because of how far the path stretches, from one coast to the other, so you don't want to miss it! Happy eclipse viewing, everyone!