WAYNE, Neb. | Todd Young can't help looking up to the sky.

As the professor of physics and astronomy for Wayne State College and director of the college's Fred G. Dale Planetarium, it's sort of his job to keep his peepers prone to the planets.

But on Aug. 21, he (and potentially millions of other people) will be gazing up to the heavens.

That's when the total solar eclipse will cross the continental United States. 

Simply put, a solar eclipse occurs when the moon passes between the earth and the sun, which totally or partially obscures the image of the sun for folks living on earth.

On the other hand, a total solar eclipse happens when the moon's apparent diameter is larger than the sun's. This blocks all direct sunlight, plunging day into darkness.

Suffice it to say, solar eclipses in the U.S. are quite rare. The last solar eclipse occurred in 1991, but was only visible in parts of Hawaii. Before that, a total solar eclipse occurred in the Pacific Northwest in 1979. 

The August eclipse will be the first with a path that crosses the country's Pacific and Atlantic coasts since 1918, Young said.

For most of this summer, Young has dedicated his Saturdays to talking about "The Great American Solar Eclipse" -- a 45-minute full-dome show and astronomical lesson -- which amounts to being a primer for people who aren't afraid of the dark.

Young's "The Great American Solar Eclipse" presentation will continue at 2 p.m. on Aug. 12 and Aug. 19 at the Fred G. Dale Planetarium, located in the Carhart Science Building on the Wayne State College campus. 

In addition, each guest will receive a free pair of eclipse glasses at the end of the program.

Oh, did we forget to mention that no matter what you do, don't watch an eclipse without special glasses? 

"That's the one thing that I stress with kids," Young said. "Staring directly into the sun is dangerous. Staring into a total solar eclipse is even worse."

Can't you get away with a nice pair of sunglasses? Apparently not.

"You need lenses that are designed specifically to filter out enough of the light that it doesn't burn a hole through your retina," Young advised. 

Many retail and online stores currently sell such glasses geared specifically for Aug. 21.

OK, can you see the solar eclipse all over the United States? Well, you can see a partial eclipse (where the moon covers only a part of the sun) anywhere in North America.

To see the total solar eclipse (where the moon fully covers the sun), you'll need to be in a relatively thin ribbon (about 70 miles wide) that crosses the U.S. from the West to East Coast.

Hmm ... but will you be able to be in that path in Wayne? Well, not ideally. The best place to see the total solar eclipse in the Cornhusker State is somewhere between North Platte and Lincoln.

Barring cloudy or rainy skies, the eclipse should occur between 12:54 and 1:03 p.m. depending on where in Nebraska you are. The expected duration should be around two minutes, 30 seconds.

Well, that's not as long as we thought it would be. If we can't catch it this time, will we have to wait for a long time?

It all depends on the definition of a long time. According to Young, the next partial eclipse will occur in 2024, while the next total solar eclipse won't occur any time soon.

"A total solar eclipse occurs on a given spot on the planet only once every 375 years," he said. "If you don't catch it this time around, be prepared to wait for a long, long time."  

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