The May 20th Annular Eclipse is definitely something you want to see for yourself, but looking straight at the Sun without proper eye protection can cause permanent, significant vision loss.
Your retinas don’t have pain receptors, so if you ignore this warning and look at the Sun directly, it won’t hurt while you ruin your eyesight. Ophthalmologists (medical doctors who specialize in conditions and diseases of the eye) have a word for this kind of vision loss: Solar Retinopathy. I like to call it, “Fried Eyes Syndrome.”
Look at the image below – that’s the retina of a human eye that’s been damaged by looking directly at the Sun. Those dark areas in the center of the image are where sunlight has literally cooked the surface of the retina.
So what do you do to observe the eclipse while avoiding Fried Eyes Solar Retinopathy?
You’ve got lots of options. The Planet Fun Store at Clark Planetarium sells a variety of solar viewing filters that are designed to be worn like sunglasses or slipped over the front of your binoculars or telescope. These will not only come in handy for the May 20th Annular Eclipse, but also the June 5thTransit of Venus and the August 21, 2017 Total Eclipse of the Sun that will be visible in much of the U.S.
Even better, any time there’s some significant sunspot activity (as expected next year) you can use these filters to look at sunspots.
- Sunglasses, even doubled-up, even polarized. They don’t block enough light.
- Smoked glass. The soot coating is very difficult to get to just the right thickness, and it rubs off way too easily.
- Exposed Black & White film. 1) Who on Earth still has film these days? and 2) The odds are hugely against you having the right kind of film and properly exposing and then developing it to make it useful as a solar filter.
- Welders Goggles. Unless they’re Grade 14 or stronger and specifically made for arc welding, they don’t provide adequate protection.