Diamond ring effect as seen from Scottsville, Kentucky during the 2017 total solar eclipse.
Caption

Diamond ring effect as seen from Scottsville, Kentucky during the 2017 total solar eclipse. / Getty Images

On Monday, April 8, the moon will slip in front of the sun, blocking its light and creating an eerie twilight in the middle of the day. Stars will come out, the air will get cold and colors will dance around the horizon. This is the full-body experience that is a total solar eclipse.

Viewers along a 100-mile wide ribbon of land stretching from Texas to Maine will be lucky enough to be in the path of totality – where observers can watch as the moon completely covers the sun. Though every contiguous U.S. state, plus parts of Alaska and Hawaii, will experience at least a partial solar eclipse.

The last total solar eclipse to cover part of the United States happened in August 2017. But its path this year is much wider and will run through more urban areas, which means more people may find it easier to travel to the path of totality.

How to safely admire the eclipse

No matter where you are it's crucial to use eye protection if you plan on looking at the eclipse.

If you're viewing the partial eclipse, you should keep them on the entire time. If you're in the path of totality, you can take off your eclipse glasses when the sun is completely covered by the moon.

It's unlikely that one quick glance at the sun will cause serious damage. But one eclipse chaser and eye specialist at the University of Waterloo in Canada, Ralph Chou, says that at a certain point, these quick glances can add up and damage the light-sensitive part of the retina.

"Typically what will happen is: You look at the eclipse as it is happening without protection, your eyes don't appear to be damaged, everything is fine," Chou says. But then, "the next morning, you wake up and look in the mirror or across the breakfast table at your nearest and dearest, you suddenly realize you can't see their face."

The American Astronomical Society has a list of vetted solar viewer sources on their website.

If you don't feel comfortable using glasses, you can still enjoy a partial eclipse through a pinhole projector following these simple steps:

  1. Outside, stand with your back to the sun.
  2. Let sunlight shine over your shoulder and through something with small holes (like a pasta colander, a straw hat or even a piece of cardboard with a hole in the center).
  3. Enjoy the crescent suns projected onto the ground!

From an ephemeral moment to a lifetime of wonder

For some people, an eclipse is no big deal. But for eclipse chasers, these solar events are life changing.

And for others, it's can be the impetus for a future career. Take space physicist Laura Peticolas at Sonoma State University. She told NPR that she saw a total eclipse with her dad when she was 9 years old. While she doesn't remember the actual moment of the eclipse or many details about that day, she says that in some ways, it inspired her future career.

"I really was starting to think about what exists in the universe that we can't see," she says. "And I used to just wonder about that. This was before I decided to be a physicist. And then I learned that's what physicists do and I was so excited."

But if you don't get to see a total eclipse this April, don't panic! There's a total eclipse once every year and a half or so somewhere on Earth.

Share your eclipse stories with us at shortwave@npr.org.

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Today's episode was produced by Margaret Cirino and Rachel Carlson. It was edited by Rebecca Ramirez. Nell Greenfieldboyce fact-checked. David Greenburg was the audio engineer.