7 things to know about the rare total solar eclipse crossing the nation this August

The nation is gearing up for the first total solar eclipse to cross the country coast to coast in nearly 100 years.

This August, the sun, the moon and planet Earth will all align as space junkies revel in the celestial spectacle that has everyone talking.

Due to its rarity, astronomers are calling the 2017 phenomenon the Great American Eclipse.

Here are seven things to know about the big summer event:

When is it?

The Great American Eclipse will cross the U.S. on Aug. 21, and will begin in Oregon at 10:15 a.m. local time (so, 1:15 p.m. EST). The eclipse’s path of totality will cut a 60-mile-wide arc across the country and end in South Carolina about an hour and a half later.

Most accurate map of the eclipse’s path of totality to date

NASA data visualizer Ernie Wright published the most accurate map to date of the Great American Eclipse's path of totality using data from NASA's Lunar Reconnaissance Orbiter, elevation data on Earth and information on the sun's angles.

Whether or not you’re inside the path of totality will determine what you see in the sky. If you’re outside the path, you’ll likely see a partial (not total) eclipse.

To determine the most accurate eclipse path, according to Wright, you have to figure out where the moon's shadow will fall on the Earth's surface, which requires taking into account the elevation differences on both the moon and Earth's surfaces, he told Space.com.

Using elevation data from NASA’s Shuttle Radar Topography Mission, the locations of the Earth, moon and sun at each line of latitude or longitude and how long it takes sunlight to travel to the moon and down to Earth, Wright was able to compute where exactly the eclipse will cross and for how long.

How to find out what the eclipse will look like from where you live

Scientists at the University of California, Berkeley, teamed up with Google to create a simulator that shows you what the sky will look like wherever you are.

All you have to do is type in your hometown or zip code and the simulator will tell you how much of the sun will be blocked by the moon, how the sun will travel across the sky over a three-hour period on Aug. 21 and what time to watch.

“There are lots of online animations of the 2017 eclipse, but you can’t use them like ours to get a sense of the full experience, including your surroundings. Our simulation is closer to what one might experience in a planetarium show,” the UC Berkeley scientists said.

The tool could also help people figure out where to get the best “total solar eclipse experience,” the scientists said.

This simulator is part of the Eclipse Megamovie Project, a Google-Berkeley collaboration aimed at collecting and stitching together thousands of photos of the Aug. 21 eclipse taken by volunteer photographers around the country.

Find out what the sky will look like in your city.

Where are the best places to see the 2017 eclipse?

The August eclipse will be incredibly accessible to anyone within a 200-mile drive of its path of totality, but the most important factor in getting a good view is weather.

But if you're hoping to make a trip out of the big event, Greatamericaneclipse.com has a list of 10 great places to see the phenomenon based on the best weather odds for clear skies:

Madras, Oregon: Totality begins at 10:19 a.m. PDT and lasts 2 minutes, 4 seconds.

Snake River Valley, Idaho: Totality begins at 11:33 a.m. MDT and lasts 2 minutes, 18 seconds.

Casper, Wyoming: Totality begins at 11:42 a.m. MDT and lasts 2 minutes, 4 seconds.

Sandhills of western Nebraska: Totality begins at 11:49 a.m. MDT and lasts 2 minutes, 30 seconds.

St. Joseph, Missouri: Totality begins at 1:06 p.m. CDT and lasts 2 minutes, 39 seconds.

Carbondale, Illinois: Totality begins at 1:20 p.m. CDT and lasts 2 minutes, 41.6 seconds.

Hopkinsville, Kentucky: Totality begins at 1:24 p.m. CDT and lasts 2 minutes, 41.2 seconds.

Nashville, Tennessee: Totality begins at 1:27 p.m. CDT and lasts 1 minute, 57 seconds.

Great Smoky Mountains National Park: Totality begins at 2:35 p.m. EST and lasts 1 minute, 17 seconds.

Columbia, South Carolina: Totality begins at 2:43 p.m. EST and lasts 2 minutes, 30 seconds.

Plan on traveling within or from Georgia? Head to Rabun County, about two hours north of metro Atlanta, where the eclipse will begin at 2:35 p.m. and last 2 minutes and 40 seconds.

The area is also holding an array of events to commemorate the phenomenon.

Other accessible road trips from Georgia include the Great Smoky Mountains; Columbia, South Carolina and Nashville, Tennessee.

If you plan on seeing the spectacle in person, Space.com has helpful safety tips.

More about how Georgians can catch the event.

How to watch the eclipse live (from your couch)

Even if you don't plan on traveling or making your way outdoors for the great eclipse, NASA will be hosting an Eclipse Megacast across multiple programming venues, including NASA TV, YouTube, UStream and more. Local and national television stations will likely pick the Megacast up as well.

When was the last time there was a total solar eclipse visible from the United States?

The total solar eclipse of July 11, 1991 in Hawaii was the last to touch U.S soil, but the Feb. 26, 1979 eclipse — 38 years ago — was the last visible within the continental United States.

How long until the next total solar eclipse to touch the continental United States?

The next North American total solar eclipse will be on April 8, 2024, and will begin in Mexico, make its way through Texas to Maine and eventually end in Canada.