How to safely watch the solar eclipse — even if you’re not in the line of totality

partial solar eclipse

Most days we barely give the giant, searing-hot ball of plasma in the sky a second thought.

That will change dramatically on Monday, August 21: when the total solar eclipse sweeps across the continental United States for the first time in nearly 100 years.

If you’re not careful, though, the sun still will rapidly scorch your eyeballs.

While the moon will at least partially block the sun for the entire nation, the glowing crescent left behind will emit ultraviolet rays — the same light that causes sunburn — and could damage the light-sensing cells of your eyes’ retinas. Even looking with normal sunglasses can lead to solar retinopathy, a condition that can temporarily blind you, lead to missing spots in your vision, or even cause permanent blindness.

The only safe time to look at the solar eclipse with the naked eye, according to NASA, is during totality: where the moon’s fullest, darkest umbral shadow touches. But only a small piece of America will experience its magic (and for less than three minutes of the entire two- to three-hour eclipse, depending on the location).

united states us total solar eclipse map august 21 2017 nasa gsfc svs

The good news is that there are several simple and safe ways to safely watch the partial eclipse — even if you’re not in the path of totality, or you are and want to look at the sun beforehand.

Here are seven safe and simple methods to watch.

SEE ALSO: Solar eclipse die-hards use this clever trick to watch totality longer than anyone on Earth

DON’T MISS: Total solar eclipses are going extinct

1. Solar glasses or viewers

If you’re just now reading this and hope to buy a pair of eclipse sunglasses, or a one-sheet viewer, you may be out of luck — many online retailers are selling out.

If you have a friend who’s an astronomy buff, though, chances are high they’ll have an extra pair collecting dust. You might also stop into your local library, astronomy club, or NASA event site and try to grab a free solar viewer.

NASA has also compiled a list of reputable manufacturers, sellers, and brands that meet strict standards — but beware of unscrupulous sellers pushing knock-off eclipse glasses to make a buck off desperate buyers. (If something seems fishy, it probably is.)

2. Welder’s glass rated shade-12 or higher

Day-in and day out, welder’s glass is designed to protect a worker’s eyes from bursts of UV light that acetylene torches give off. This can also make them great to look at the sun.

NASA recommends shades 12, 13, or 14, with shade 12 being the least-opaque of the three grades. “Many people find the Sun too bright even in a Shade 12 filter, and some find the Sun too dim in a Shade 14 filter — but Shade 13 filters are uncommon and can be hard to find,” NASA wrote at its eclipse safety website.

But the space agency urges extra caution if you find and want to use an older welder’s helmet or glass. “If it’s less than 12 (and it probably is), don’t even think about using it to look at the Sun,” it said. 

 

3. Pinhole camera

Pinhole cameras can get pretty advanced with boxes and tripods, but NASA’s Jet Propulsion Laboratory has instructions for an incredibly simple version that you can build in a few minutes.

Grab some scissors, tin foil, a piece of thick card stock (or paper), tape, and a needle. Cut a hole in the middle of one sheet of card stock, tape the edges of a tin foil section over it, then carefully pierce the center of the foil with the needle — presto, you’ve made a pinhole camera. Hover your device over something white, ideally a piece of paper, and move it up and down until you figure out where the ideal focus point is.

But you don’t even need to even build something. Any object with tiny holes that will let light through works. A kitchen strainer, for example — or just closing your fist to barely let a point of light through — can make for a proper pinhole camera.

See the rest of the story at Business Insider

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s