How to Safely See a Solar Eclipse
A solar eclipse needs to be seen, but only at the expense of your eyes – looking at one of them the wrong way can cause long-term damage to your vision. It is ironic (if absolutely necessary) that we advertise these phenomena as visual spectacles that we must also resist by looking at them with the naked eye.
As the Ring of Fire annular eclipse approaches later this month, promising to illuminate the edges of the moon with scorching sunlight, it’s important to know that you can technically look at an eclipse – you just need the right tools and know-how. this without risking your eyes.
How viewing an eclipse can damage your eyes
This is not an old suburban myth like the myth of the dangers of swimming unless you wait exactly 30 minutes after eating, but verifiable medical advice: You definitely shouldn’t look at an eclipse with the naked eye. As Dr. Ralph Chow explained to NASA in 1997, looking directly at the Sun during an eclipse can cause “eclipse blindness” or retinal burns. “
Zhou described how and why the overwhelming light generated by an eclipse is very harmful to your eyes:
Exposure of the retina to intense visible light causes damage to the photosensitive cells of the rod and cones. Light triggers a series of complex chemical reactions in cells that damage their ability to respond to visual stimuli and, in extreme cases, can destroy them.
The severity of this damage will depend on the duration of exposure. It is quite possible, God forbid, you will completely lose your sight, looking directly at the eclipse. This is why, according to Zhou, “it is never safe to look at a partial or annular eclipse or partial phases of a total solar eclipse without the proper equipment and techniques.” Listen to medical professionals, guys (and maybe not the disgraced former president ).
How to safely observe a solar eclipse
The first thing to remember is that regular sunglasses will not protect you from the harmful effects of looking at an eclipse, no matter how dark they are. This also applies to simply looking at the sun when it is not in an eclipse phase. This giant, eternally burning ball of gas, 93 million miles from our planet, has supported all known carbon life forms for billions of years; you can’t joke with that. The only time it is largely safe to look at the sun during a solar eclipse is during the “totality” phase when the sun is completely obscured by the moon.
Chris Westphal, a photographer who has captured multiple images of multiple eclipses, told Lifehacker a little more about the tricks of a complete eclipse observation:
It is only during a total solar eclipse that you can look at it, but even then it is highly recommended to know exactly when the totality begins and ends, because if you look at the sun before or after these moments, it can lead to permanent damage to the eyes or even blindness.
Except it is rare to know exactly when the totality will occur, you need the right equipment. Fortunately, eclipse glasses are widely available and inexpensive, but you need to watch out for fakes. One of the most important certifications to look out for is that the glasses are approved by the International Organization for Standardization, which labels certified products with the “ISO” mark.
According to Space.com , ISO approved sunglasses promise you the following:
- No more than 0.00032 percent of sunlight can pass through the filters.
- The filters should be free of any defects such as scratches, bubbles and dents.
- Portable viewers must be large enough to cover both eyes.
- Viewers (or packaging) labels must include the manufacturer’s name, instructions for safe use, and warnings about the dangers of misuse.
There are many companies that make glasses for safe viewing of eclipse. However, if you want to be more than just your average viewer, Westphal recommends the “white light filter on a telescope or the more technical Hydrogen-Alpha telescope ,” the latter of which is used by astronomers to observe the Sun’s atmosphere.
Either way, the key is to respect the sun and the retina at the same time – which you can do with the right equipment on hand.