SciFri: Solar Eclipse 5/20/2012!

Abram Nothnagle takes us to the frontiers of science. Every Friday.

On Sunday there was a solar eclipse visible in the United States and around the world. I hope all of you managed to get a look at it. I know I did.

This was the first time in my life that I actually witnessed a solar eclipse for my self, and while amazing, it wasn’t nearly as spectacular here in Iowa as it was elsewhere in the world. I still took pictures though.

With any partial eclipse, there is still too much light getting in from the sun to make it safe to look at directly, so inventive measures must be taken in order to even get a glimpse of the event. In pictures like the one from Texas, the sun has already begun to set, which means that there is enough atmosphere between the sun and the observer to allow pictures to be taken. Like the picture from Nevada, it is also possible to view the eclipse through a storm cloud without injury, but how can we view the eclipse if we aren’t fortunate enough to be in the right place at the right time? It’s actually fairly easy: you can buy special glasses, or use the “pinhole” technique.
There exist special “eclipse glasses” that are heavily tinted to allow the user to safely view the sun. Normal sunglasses aren’t strong enough to keep an observer safe; in fact, very few things are. Even minimal exposure to intense sunlight can cause permanent blindness. Because of this, eclipse glasses are so opaque that the only thing you can see through them is the sun.

One of the few safe ways to directly view the sun

The other common technique for viewing solar eclipses is indirect. It is called the “pinhole” technique. Basically, you can look at the sun through an extremely small hole because not enough light will get through to obscure the image or cause any damage. Usually pictures are taken through something called a pinhole lens that uses this method. The pinholes are often too small for humans to see through. If we aren’t taking a picture of the sun, then light can be shown through the pinhole onto a piece of paper to get a “shadow” of the eclipse.

Find more where this came from at Abram’s personal blog, www.sciencemanblog.blogspot.com.