The Exploratorium’s Guide to Eclipse 2017

Are you ready to enjoy the August 21, 2017 solar eclipse? Get the most out of your viewing experience with these tips, tricks, and best practices.

On August 21, 2017, a total solar eclipse will cross the continental United States, from Oregon to South Carolina. The best place to watch the eclipse will be along the path of totality. The second best place will be at the Exploratorium or on our website. With the support of NASA, we’ll be sending field crews to two different locations along the path of totality. They’ll bring high-powered telescopes and high-end video gear to transmit a stunning live broadcast of the total solar eclipse. Kind of like this amazing one we filmed in Micronesia last year.

For those who are on the path, planning to travel to the path, or expect to be in the continental United States (everyone here will experience at least some partial eclipse magic and the Bay Area will see 80% coverage of the sun), here are a few things you can start doing now to maximize your Eclipse 2017 experience:

1. Be like Galileo and build a solar viewer.

Seeing the total solar eclipse is a breathtaking experience, but it can also be dangerous. Other than during totality, when the moon is fully covering the face of the sun, it’s not safe to watch an eclipse with your naked eye. No, really, we mean it. Don’t do it.

Totality: The only time it's OK to look right at the sun. (Photo by Phoebe Tooke/Exploratorium)

Since totality will only last between 2 and 2.5 minutes, depending on where you are, the majority of eclipse-gazing time will not be safe for your eyeballs. So, instead of looking straight at the partially covered sun, you’ll need to use a solar viewer—just like Galileo did. Here’s a way to build one using two pieces of white cardboard, a T-nut, a tripod, some PVC pipe, and a pair of binoculars. This is a safe way to project an image of the sun any day—eclipse or shine!

2. Bring out the slotted spoon and play with projections.

You can also project images of the sun year-round using a few simple techniques. All you really need is a pinhole, which you can cut out of a piece of paper, or just overlap your fingers like so:

(Photo by Nancy Rodgers/Exploratorium) 

A colander also works particularly well for projecting images of the sun. Try experimenting with this on a sunny day so that you get a sense of how to do it and what the sun typically looks like. Having something to compare will make the eclipsed sun all the more stunning.

3. Gear up with eye protection.

OK, so you’re going to want to look up. We get it. But in that case, you have to be safe about it. Buy a pair of solar viewing glasses. They’re designed to block sunlight during a partial eclipse (or anytime) and will save your retinas from those harmful rays. You can also visit a local welding shop and purchase a piece of #14 welder’s glass. This is the darkest shade of welder’s glass and will keep your eyes safe while looking at the sun.

4. Learn the solar lingo.

You know what Beyoncé says: “If you liked it, then you should have put a ring on it.” Well, the sun is definitely listening to Queen Bey: each total solar eclipse has two diamond rings.

Diamond ring as seen from Micronesia during the 2016 total solar eclipse. (Photo by Phoebe Tooke/Exploratorium)

You’ll also be able to marvel at the sun’s corona and keep an eye out for Bailey’s beads, not to mention any prominences. Dive into what these things are so that you’ll recognize them when they happen.

5. Make a model.

Why won’t everyone in the U.S. see totality? Well, even as the eclipse crosses the country, the path of totality will only be approximately 100 miles wide. This path is based on the umbra, which is the shadow the moon casts on the Earth. Where the umbra goes, totality follows. With the help of a friend and some everyday materials, you can model this for yourself.   

Want to learn more about eclipses? Here are five things you probably didn't know.