Many people are aware of the admonition to avoid looking at the sun.
According to Professor Richard Ignace, a research astronomer at East Tennessee State University, some folks may think that doesn’t apply during an eclipse.
“If you don’t have eclipse glasses, the key thing is not to look directly at the sun,” he said. “Even at 98 percent you really shouldn’t look. Instead you can make a pinhole viewer. A good one is a piece of cardboard and you just poke a little hole through it with a needle or maybe even a nail.”
When the light passes through the pinhole as the moon moves across the path of the sun, the shape of the eclipse will be projected onto another smooth, flat surface placed beneath it. Ignace said people should never look through the pinhole directly at the eclipse.
NASA has provided the following safety tips for eclipse viewing on its website:
• Never look directly at the sun.
• Use only “eclipse glasses” or handheld solar viewers verified to be compliant with the ISO 12312-2 international safety standard for such products. Ordinary sunglasses are not sufficient.
• Always inspect your solar filter before use; if scratched or damaged, discard it. Read and follow any instructions printed on or packaged with the filter.
• Always supervise children using solar filters.
• Stand still and cover your eyes with your eclipse glasses or solar viewer before looking up at the bright sun. After looking at the sun, turn away and remove your filter — do not remove it while looking at the sun.
• Do not look at the uneclipsed or partially eclipsed sun through an unfiltered camera, telescope, binoculars or other optical device.
• Similarly, do not look at the sun through a camera, a telescope, binoculars or any other optical device while using your eclipse glasses or handheld solar viewer — the concentrated solar rays will damage the filter and enter your eye(s), causing serious injury.
• Seek expert advice from an astronomer before using a solar filter with a camera, a telescope, binoculars or any other optical device. Note that solar filters must be attached to the front of any telescope, binoculars, camera lens or other optics.
• If you are within the path of totality, remove your solar filter only when the moon completely covers the sun’s bright face and it suddenly gets dark. Experience totality, then, as soon as the bright sun begins to reappear, replace your solar viewer to look at the remaining partial phases.
• Outside the path of totality, you must always use a safe solar filter to view the sun directly.
• If you normally wear eyeglasses, keep them on. Put your eclipse glasses on over them, or hold your handheld viewer in front of them
The Greeneville City Schools System recommends that eclipse glasses be purchased from federal government approved vendors such as American Paper Optics, Rainbow Symphony, Thousand Oaks Optical and TSE 17.