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Total solar eclipse on August 21

Today – August 21, 2017 – a total eclipse of the sun happens in the continental United States for the first time since February 6, 1979. In other words, the moon’s dark shadow hasn’t hit anywhere in the contiguous US or Alaska for over 38 years. It’s been a mighty long time!

Enter your zip code to learn how much eclipse you’ll see, and what time

How to watch the solar eclipse safely

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Looking for a solar eclipse viewing party? Try this page

In fact, it’s been over 99 years since the moon’s dark umbral shadow has traveled all the way across the mainland US from the Pacific Coast to the Atlantic Coast. This last happened on June 8, 1918.

Map of all total solar eclipses visible from North America 1951 to 2000 via Fred Espenak, NASA’s GSFC.. The last time the moon’s dark shadow hit the mainland U.S. was on February 26, 1979.

Although totality begins at sunrise over the Pacific Ocean and ends at sunset over the Atlantic Ocean a little over 3 hours later, this total solar eclipse is only visible on land from the United States. But at any single spot along the total eclipse path, the total eclipse of the sun lasts for a maximum of just over 2 minutes and 40 seconds.

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How astronauts aboard ISS will see the eclipse

See the tiny black dot crossing the United States in this this animation of the August 21 solar eclipse? It’s only here that you can see a total eclipse of the sun. But everyplace within the much larger gray circle will see a partial eclipse. Click here for a more detailed map.

Unless you’re quite practiced at using a telescope and have a proper filter, don’t even try watching the partial solar eclipse through the telescope. Your best bet is to locate an astronomy club or an observatory near you that might be hosting a public viewing of this natural spectacle. Find an astronomy club here.

You don’t need a telescope or an optical aid to view this eclipse, but you do need proper eye protection. Safely and inexpensively watch this partial eclipse with eclipse glasses, or make a simple pinhole projector to indirectly view the solar eclipse, as explained here. You can also turn the telescope or binoculars into a pinhole camera, to indirectly and safely view any solar eclipse.

Moon that’ll cover sun on August 21 is called a Black Moon

Earth’s eclipses are special

Trees serve as natural pinhole projectors, casting images galore of the partial solar eclipse. Image credit: torbakhopper

Trees serve as natural pinhole projectors, casting images galore of the partial solar eclipse. Image credit: torbakhopper

As shown in the above photo above, trees serve as natural pinhole projectors, casting leaf shadows and images of the eclipse galore. When you see the scene for yourself, you may want to sing along with the Beatles:

Images of broken light which dance before me like a million eyes, they call me on and on across the universe.

Safe solar eclipse watching

We present some eclipse calculators, which will enable you to find out eclipse times in your sky. The US Naval Observatory and NASA give the eclipse times in Universal Time. You must convert Universal Time to your local clock time. Subtract 3 hours for ADT, 4 hours for EDT, 5 hours for CDT, 6 hours for MDT, 7 hours for PDT and 8 hours for AKDT.

Interactive Map via NASA (click on the map for eclipse times in Universal Time)

Eclipse computer via the US Naval Observatory gives eclipse times in Universal Time.

How do I convert Universal Time into my time?

EclipseWise gives the eclipse times in Local standard time, so if you’re on daylight saving time, you must add one hour. Timeanddate.com gives the eclipse times in your local time, so no conversion is necessary.

Solar eclipse calculator via EclipseWise (in local standard time)

Eclipse calculator via TimeandDate (in local time)

Total eclipse of sun: August 21, 2017

Bruce McClure