How to Watch a Solar Eclipse – Science Guides – The New York Times

August 16, 2017

How to Watch #Eclipse2017 “Totality” is cosmically special: sun is 400X larger than moon but also 400x farther away


This perfect sun-moon-Earth alignment is an extraordinary cosmic coincidence. The sun is 400 times larger than the moon, but it also happens to be 400 times farther away, which to the observer on the ground means they are almost identical in size. The match is so uncanny that on some occasions, the moon is at the farthest point of its slightly elongated orbit and fails to cover the sun fully, leaving a ring of sunlight. …In all
the hundreds of billions of star systems of our Milky Way galaxy, few are likely to produce total solar eclipses like ours.

The moment when the moon passes completely in front of the sun, an event called “totality,” will begin in Lincoln City at 10:16 a.m. PT and travel to the other side of the country, and exiting at
Charleston, South Carolina at 2:48 p.m. ET. The entire journey takes about an hour and a half.

Even if you are not in the path of the total eclipse, a partial eclipse will be visible throughout the continental United States. The last remnants of the lunar shadow will finish passing over the country at 4:09 p.m.

Even though an eclipse effectively turns day into night, never look directly at the sun.

Solar eclipses are especially dangerous. Not because of anything special about the light during the eclipse, but because the sudden changes in luminosity can cause retina damage before your eyes have a chance to adapt, or before you have an opportunity to look away.

Do wear eclipse glasses. The only safe way to view the eclipse during its partial phases is to wear eclipse filters. We already suggested a few you should consider, but even if you don’t go with those, glasses that meet the proper international safety standards should have a certification of ISO 12312-2.