On August 21, 2017, a global eclipse of the Sun will visibly traverse a narrow corridor across Northern America from Salem, Oregon to Charleston, South Carolina. This event will appear as a partial eclipse when viewed from southwest Riverside County. This solar eclipse begins after 9:00 a.m. locally and ends before noon. A total solar eclipse last occurred in the USA in 1979.
Looking directly at the Sun is unsafe, even during a solar eclipse. According to the American Astronomical Society* and the American Academy of Ophthalmology, homemade filters or ordinary sunglasses, even very dark ones, are not safe for looking at the Sun. The retina is easily damaged by such intense exposure.
A solar eclipse is when the moon blocks any part of the sun from our view. The bright face of the sun is covered gradually by the moon during a partial eclipse, lasting a few hours. During the brief period of a total eclipse when the moon fully covers the sun (only a couple of minutes), the light of day gives way to a deep twilight sky. The sun’s outer atmosphere (called the solar corona) gradually appears, glowing like a halo around the moon in front of it. Bright stars and planets become more visible in the sky.
Watching a solar eclipse is a memorable experience, but looking directly at the sun can seriously damage your eyes. Staring at the sun for even a short time without wearing the right eye protection can damage your retina permanently. It can even cause blindness, called solar retinopathy.
There is only one safe way to look directly at the sun, whether during an eclipse or not: through special-purpose solar filters. These solar filters are used in “eclipse glasses” or in hand-held solar viewers. They must meet a very specific worldwide standard known as ISO 12312-2.
Please keep in mind that ordinary sunglasses, even very dark ones, or homemade filters are not safe for looking at the sun.
Steps to follow for safely watching a solar eclipse
- Carefully look at your solar filter or eclipse glasses before using them. If you see any scratches or damage, do not use them.
- Always read and follow all directions that come with the solar filter or eclipse glasses. Help children to be sure they use handheld solar viewers and eclipse glasses correctly.
- Before looking up at the bright sun, stand still and cover your eyes with your eclipse glasses or solar viewer. After glancing at the sun, turn away and remove your filter—do not remove it while looking at the sun.
- Never look at the uneclipsed or partially eclipsed sun through an unfiltered camera, telescope, binoculars or other similar devices. This is important even if you are wearing eclipse glasses or holding a solar viewer at the same time. The intense solar rays coming through these devices will damage the solar filter and your eyes.
Talk with an expert astronomer if you want to use a special solar filter with a camera, a telescope, binoculars or any other optical device.
Solar eclipse glasses have met the following standards for becoming ISO certified:
- 100% harmful UV
- 100% harmful infrared
- 99.99% of intense visible light
Even if your eclipse glasses meet the safety standards, don’t use them if:
- The lenses are scratched.
- The lenses are wrinkled.
- They are older than 3 years.
An alternative method for safe viewing of the partially eclipsed sun is pinhole projection (Visit https://eclipse2017.nasa.gov/safety for directions on this indirect viewing method).
For information about where to get the proper eyewear or handheld viewers, check out the American Astronomical Society.