Solar Eclipse Glasses: How to Safely Watch a Solar Eclipse
Solar eclipse glasses are specially designed protective eyewear that allows people to look at the Sun during a solar eclipse without exposing their eyes to dangerous levels of solar radiation.
Regular sunglasses are not safe for viewing an eclipse.
Why Are Eclipse Glasses Necessary?
Looking directly at the Sun can damage the retina, the light-sensitive tissue at the back of the eye.
During an eclipse, the Moon blocks part of the Sun, which can make people feel more comfortable looking toward it. However, harmful solar radiation can still reach the eyes.
Specialized eclipse glasses use solar filters that dramatically reduce the amount of visible light and other solar radiation reaching the eyes.
What Makes Eclipse Glasses Different?
Authentic solar-viewing glasses are much darker than ordinary sunglasses.
They are designed specifically for direct solar observation and should comply with recognized safety standards for solar viewers.
When wearing properly made eclipse glasses, the Sun should appear as a bright, sharply defined disk, rather than appearing overwhelmingly bright.
Can Regular Sunglasses Be Used?
No.
Ordinary sunglasses—even very dark ones—do not provide adequate protection for directly viewing the Sun.
Using multiple pairs of sunglasses together is also not a safe substitute for certified solar-viewing glasses.
How to Use Eclipse Glasses
Before looking toward the Sun:
Put the eclipse glasses on while facing away from the Sun.
Make sure the filters are securely covering your eyes.
Look toward the Sun only through the solar filters.
Remove the glasses only after turning away from the Sun.
Children should always be supervised during solar-eclipse viewing.
Check the Glasses Before Use
Solar viewers should be inspected before an eclipse.
Do not use glasses that have:
Scratches.
Holes.
Tears.
Cracks.
Damaged or detached filters.
If the viewing filter appears damaged, it should not be used.
What About Cameras and Telescopes?
Solar eclipse glasses protect your eyes, but they do not automatically protect cameras, binoculars or telescopes.
Optical equipment needs appropriate solar filters specifically designed for the front of the equipment.
Never look through an unfiltered telescope or binoculars at the Sun, even while wearing eclipse glasses.
Total Solar Eclipse Exception
During a total solar eclipse, there is a brief period called totality when the Moon completely covers the Sun.
During totality, direct viewing can be possible without eclipse glasses. However, the glasses must be put back on before any part of the bright Sun becomes visible again.
This exception does not apply to partial or annular eclipses.
Conclusion
Solar eclipse glasses are an important safety tool for observing an eclipse.
Use properly manufactured solar viewers, never ordinary sunglasses, and inspect them before use. With the right precautions, a solar eclipse can be an exciting and safe astronomical experience.