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Here's How Long Does The Solar Eclipse Will Last

You've been hearing about it for weeks now, and it's nearly here. The first total solar eclipse across the entire United States since 1918 will cast its shadow on Aug. 21, and you know you're going to want to check it out. But how long does the solar eclipse last, and how much time do you have to see this miraculous alignment of the sun, moon, and earth? There are a few key factors to consider, as it will all vary depending on your location.

In case it's been a while since your middle school earth science class, here's what a total solar eclipse actually means: As the moon and sun cross paths, a shadow is cast, causing an eclipse. While orbiting on the morning of the 21st, the moon will be closest in its elliptical pattern to the earth, and will be a new moon (aka, its dark face will be pointing toward earth). When everything perfectly aligns in this way, the area within the middle of the eclipse's shadow (a 70 mile-wide expanse) will see the entire "totality," as its called, of a full solar eclipse. The lucky ones living within this 70-mile path will see the moon cover the sun, and daylight will dim for a few minutes.

But let's say you don't live within the totality. Can you still see the eclipse? Yes, you will see something, but not to the same degree as those living right in the sweet spot; you'll catch a partial eclipse instead. The map below shows the total solar eclipse's path, starting up in Oregon and sweeping down through South Carolina.

The solar eclipse will glide across the continental United States, starting on the West Coast at around 8:46 a.m. Pacific Time. The moon won't fully eclipse the sun until 9:05 a.m. Pacific Time, at which point the long cast shadow will extend over the entire country. The whole experience wraps up at around 4:06 p.m. Eastern Time, ending on South Carolina's east coast.

The length of the solar eclipse will vary based on your location of course, but no experience will last less than a few minutes. Want to get really technical and plan out your eclipse viewing experience? Xavier Zuber's interactive solar eclipse Google map allows users to click their location, which leads to data showing exactly when your total or partial eclipse will begin and end. Click on your home town and set your phone alarm for Monday's event — it only happens once in a lifetime.