Safely watching solar eclipse
With excitement leading up to the August 21 solar eclipse, people across North America are preparing to watch the event. But while tempting, there are...
With excitement leading up to the August 21 solar eclipse, people across North America are preparing to watch the event. But while tempting, there are a number of safety precautions one has to take before trying to catch a glimpse of the eclipse, writes AFP. Why is it dangerous to look at the solar eclipse directly specially at that moment? Well, in general (during non-eclipse times), you've probably been told not to stare at the sun.
This is because the sun simply outputs more power than our eye is designed to handle, and exposing our eye to that kind of power can damage the retina. And in a nutshell, solar eclipses are dangerous because the sun can come out from behind the moon and "surprise you" before you have a chance to look away.
And this is actually even worse than when you normally look away from the sun because during the total eclipse, it is dark out, and your pupil therefore dialates so that it can let in enough light to get a good picture. Then, when the sun reappears and starts flooding the area with really bright light, not only are you staring straight at it, but your eye is in a state where it is wide open, and actively trying to let in as much light as possible.
This explains why it is easy to damage your eye when watching a total solar eclipse, and why you should either be sure to time it very carefully (and allow for a good margin of error), or just view the thing through one of those sets of cheap "dark" glasses they sell for the express purpose of looking at the sun without getting hurt, according to physlink.com (http://www.physlink.com/education/askexperts/ae586.cfm).
Regular sunglasses won’t block enough light. You’ll need glasses that filter all but 0.003 percent of visible light and block out most ultraviolet and infrared as well. “Such filters usually have a thin layer of aluminum, chromium or silver deposited on their surfaces that attenuates ultraviolet, visible, and infrared energy,” NASA’s eye safety page explains. Using photo or X-ray film is not safe, writes Vox.Com.