A view of the United States during the total solar eclipse of Aug. 21, 2017, showing the umbra (black oval), penumbra (concentric shaded ovals) and path of totality (red). This version includes images of the sun, showing the star's appearance in a number of locations, each oriented to the local horizon.

With 2017 right around the corner, it's time to start getting ready for the "Great American Total Solar Eclipse," NASA announced this week.

For the first time in nearly 100 years, a solar eclipse will sweep across the entire continental United States, happening on Monday, Aug. 21, 2017. It will be a once-in-a-lifetime opportunity for most skywatchers, so don't miss out!

As the moon passes before the sun, it will cast a dark shadow that begins at 10:15 a.m. PDT (1:15 p.m. EDT) on the West Coast near Salem, Oregon, before traveling cross-country to Charleston, South Carolina, where it will end at 2:48 p.m. EDT, according to a NASA press release. [Total Solar Eclipse 2017: When, Where & How to See It (Safely)]

A view of the United States during the total solar eclipse of Aug. 21, 2017, showing the umbra (black oval), penumbra (concentric shaded ovals) and path of totality (red). This version includes images of the sun, showing the star's appearance in a number of locations, each oriented to the local horizon. (Image credit: NASA/Goddard Space Flight Center Scientific Visualization Studio)

Viewers along the line between those two cities will experience a few seconds of totality, or complete darkness, while the rest of the country will be able to see the eclipse in its partial form. During a partial solar eclipse, the moon appears to have taken a bite out of the sun. The sky won't get nearly as dark as it does in the path of totality, and the partial eclipse will start earlier and end later than the total eclipse. [Total Solar Eclipse: What to Expect as Moon Blocks Sun (Photos)]

While skywatchers are making plans to see the eclipse in the best possible locations, researchers are preparing to do some serious science experiments during the event. At an American Geophysical Union (AGU) meeting in San Francisco on Wednesday (Dec. 14), scientists from NASA, the University of Texas at Arlington and the University of Hawaii gave presentations about the science of solar eclipses.

Graphic depicting the geometry of a total solar eclipse (Image credit: NASA)

"An eclipse teaches us so many things, but the 2017 eclipse is especially unique because of the uninterrupted land masses it will pass over," Lika Guhathakurta, a NASA astrophysicist, said in a statement. "This will allow us to maximize our chance to collect data and connect the shadow of the moon to Earth science."

For example, a total solar eclipse provides an opportunity for scientists to look at the sun's corona, or outer atmosphere, which will appear as rays of white light surrounding the moon. The sun's corona can reveal information about solar flares, coronal mass ejections and the solar wind — a stream of charged particles constantly flowing out of the sun and into space.

"There is a whole spectrum of colors of light that our eyes cannot see," University of Hawaii astronomer Shadia Habbal said in the AGU meeting. "From these different colors, we can directly probe into the physics of the corona."

The sun’s outer atmosphere, or corona, on March 29, 2006 was surprisingly full of structure even though the sun then was at its minimum activity. The corona displayed at least six long, beautiful streamers that extended almost symmetrically in opposite directions, like a bow tie or pair of butterfly wings, before tapering off into the deep, velvety-blue sky. Note how the prominent hairlike brushes delicately traced magnetic-field lines above the sun’s polar regions. (Image credit: Imelda B. Joson and Edwin L. Aguirre)

You don't have to be a scientist to appreciate the sight of the Great American Total Solar Eclipse. But you do need to practice safe-viewing techniques to avoid damaging your eyes. It's never a good idea to look directly at the sun, even during a total or partial eclipse. We recommend finding a (cheap) pair of eclipse glasses, though these are not the only way to protect your eyes while watching an eclipse. For more tips on safe eclipse viewing, check out this Space.com infographic.

Email Hanneke Weitering at hweitering@space.com or follow her @hannekescience. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.