How to View a Solar Eclipse Safely (courtesy of aas.org)
Looking directly at the Sun is unsafe except during the brief total phase (“totality”) of a total solar eclipse, when the Moon entirely blocks the Sun’s bright face, which happens only within the narrow path of totality. To find out whether your home or any other specific location is within the roughly 115-mile-wide path through Texas on April 8, 2024, North American total solar eclipse, see Xavier Jubier’s Google Map, which supports zooming in to street level.
During a partial or annular (ring) solar eclipse, such as the one coming through Texas on October 14, 2023, there is no time when it is safe to look directly at the Sun without using a special-purpose solar filter that complies with the transmission requirements of the ISO 12312-2 international standard.
The only safe way to look directly at the uneclipsed, partially eclipsed, or annularly eclipsed Sun is through special-purpose solar filters, such as “eclipse glasses” (example shown at left) or handheld solar viewers. Homemade filters or ordinary sunglasses, even very dark ones, are not safe for looking at the Sun; they transmit thousands of times too much sunlight. See the AAS list of Reputable Vendors of Solar Filters & Viewers page for a list of manufacturers and authorized dealers of eclipse glasses and handheld solar viewers verified to be compliant with the transmission requirements of the ISO 12312-2 international safety standard for such products.
Texas Eclipse Viewers are from the premier reputable vendor, Rainbow Symphony, and are verified to be compliant with the ISO 12312-2 international safety standard
Instructions for the safe use of solar filters/viewers:
- Always inspect your solar filter before use; if scratched, punctured, torn, or otherwise damaged, discard it. Read and follow any instructions printed on or packaged with the filter.
- Always supervise children using solar filters.
- If you normally wear eyeglasses, keep them on. Put your eclipse glasses on over them, or hold your handheld viewer in front of them.
- 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, partially eclipsed, or annularly eclipsed Sun through an unfiltered camera, telescope, binoculars, or other optical device.
- Similarly, do not look at the Sun through a camera, telescope, binoculars, or any other optical device while using your eclipse glasses or handheld solar viewer — the concentrated solar rays could 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, 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 inside the path of totality on April 8, 2024, remove your solar filter only when the Moon completely covers the Sun’s bright face and it suddenly gets quite dark. Experience totality, then, as soon as the bright Sun begins to reappear, replace your solar viewer to look at the remaining partial phases. Note that this applies only to viewing without optical aid (other than ordinary eyeglasses). Different rules apply when viewing or imaging the Sun through camera lenses, binoculars, or telescopes; consult an expert astronomer before using a solar filter with any type of magnifying optics.
- Outside the path of totality, and throughout a partial or annular solar eclipse, you must always use a safe solar filter to view the Sun directly.
Note: If your eclipse glasses or viewers are compliant with transmission requirements of the ISO 12312-2 safety standard, you may look at the uneclipsed or partially eclipsed Sun through them for as long as you wish. Furthermore, if the filters aren’t scratched, punctured, or torn, you may reuse them indefinitely. Some glasses/viewers are printed with warnings stating that you shouldn’t look through them for more than 3 minutes at a time and that you should discard them if they are more than 3 years old. Such warnings are outdated and do not apply to eclipse viewers manufactured since 2015, compliant with the ISO 12312-2 standard adopted that year, and in excellent condition. To make sure you get (or got) your eclipse glasses/viewers from a supplier of ISO-compliant products, see our Reputable Vendors of Solar Filters & Viewers page or viewers from Texas Eclipses.
An alternative method for safe viewing of the partially eclipsed Sun is indirectly via pinhole projection. I used this method for my very first partial eclipse. For example, cross the outstretched, slightly open fingers of one hand over the outstretched, slightly open fingers of the other, creating a waffle pattern. With your back to the Sun, look at your hands’ shadow on the ground. The little spaces between your fingers will project a grid of small images on the ground, showing the Sun as a crescent during the partial phases of any solar eclipse or as a ring during the annular phase of an annular eclipse. Or just look at the shadow of a leafy tree during a partial or annular eclipse; you’ll see the ground dappled with a crescent or ring-shaped Suns projected by the tiny spaces between the leaves.
A solar eclipse is one of nature’s grandest spectacles. By following these simple rules, you can safely enjoy the view and be rewarded with memories to last a lifetime. I know!! I get my eyes checked every year, after being in the path of 19 Total Solar Eclipses and 2 Annular, I have no damage to my eyes by following the practices on this page. Be Safe!!
This page is courtesy of AAS.org. For more eclipse safety tips from the AAS follow the links below :
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