Beware of fake eclipse glasses. On legitimate pairs, the lenses should have a silver appearance on the front and be black on the inside. The manufacturer’s name and address should be clearly labeled, and they should not be torn or punctured. Check, as well, for the ISO logo and the code “IS 12312-2” printed on the inside.
If you don’t have eclipse glasses, you can make a homemade pinhole projector, which lets sunlight in through a small hole, focuses it and projects it onto a piece of paper, wall or other surface to create an image of the sun that is safe to look at.
All you need is two pieces of white cardboard or plain white paper, aluminum foil and a pin or thumbtack. Cut a 1- to 2-inch square or rectangle out of the center of a piece of white paper or cardboard. Tape aluminum foil over that cut-out shape, then use a pin or thumbtack to poke a tiny hole in the foil.
During the eclipse, place a second piece of white paper or cardboard on the ground as a screen and hold the projector with the foil facing up and your back to the sun. Adjusting how far you hold the projector from the second piece of paper will alter the size of the image on the makeshift screen.
What to look for while viewing the total solar eclipse
For people along the path of totality, there are some fun milestones to keep track of as the total solar eclipse unfolds.
As the eclipse progresses and the sun gets thinner in the sky, it will start to get eerily dark, according to Tyson.
When the last beams of sunlight are about to become obscured, look out for the “diamond ring effect”: The sun’s atmosphere will appear as an illuminated halo, and the last light still visible will look like the diamond of a giant ring.
As the sunlight decreases even further, an effect known as Baily’s beads will be created by the moon’s rugged terrain. Tiny “beads” of light will be visible for only a few seconds around the dark moon, as the last bits of sunlight peer through the moon’s mountains and valleys.
When the moon is fully blocking the sun, it is safe to remove eclipse glasses and look at the total solar eclipse with the naked eye.