A solar eclipse occurs when the moon blocks any part of the sun. On Monday, August 21, a solar eclipse will be visible (weather permitting) along a narrow band across all of North America. The whole continent will experience a partial eclipse lasting 2 to 3 hours. Halfway through the event, anyone within the roughly 70-mile-wide path of “totality” will experience a brief total eclipse, when the moon completely blocks the sun’s bright face for just under two minutes, turning day into night and making visible the otherwise hidden solar corona — the sun’s outer atmosphere — one of nature’s most awesome sights. Bright stars and planets will become visible as well.
Looking directly at the sun is unsafe except during the brief total phase of a solar eclipse (“totality”), when the moon entirely blocks the sun’s bright face, which will happen only within the narrow path of totality. Marion County and Salem are in this path.
The only safe way to look directly at the uneclipsed or partially eclipsed sun is through special-purpose solar filters, such as “eclipse glasses” or hand-held solar viewers. Homemade filters or ordinary sunglasses, even very dark ones, are not safe for looking at the sun. As of July 13, 2017, four manufacturers have certified that their eclipse glasses and handheld solar viewers meet the ISO 12312-2 international standard for such products: Rainbow Symphony, American Paper Optics, Thousand Oaks Optical, and TSE 17.
- 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 glancing 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 hand-held 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.
- If you are viewing the eclipse in Marion County or Salem, remove your solar filter only when the moon completely covers the sun’s bright face and it suddenly gets quite dark. Experience totality, and then as soon as the bright sun begins to reappear, replace your solar viewer to glance at the remaining partial phases.
It is very important that you remember eye safety amidst the excitement over this natural phenomenon. Get your glasses as soon as you can so that you are prepared before the crowds rush in! Many stores are offering solar eclipse viewing glasses in areas all over Oregon. Check to make sure glasses you buy are manufactured by one of the companies listed above, and that they meet international safety standards.