Tips for the Eclipse

The Great American Solar Eclipse will be darkening our skies on August 21, 2017.  The area of totality is in a narrow strip of the country from Oregon to South Carolina, but those of us in other parts of the country will at least see a partial solar eclipse, meaning the moon never quite completely blocks the sun.  The last time that happened in the United States was 1918. 

     Partial solar eclipses happen several times a year.  Solar eclipses occur as the moon passes between the sun and the earth.  In a total eclipse, the moon completely blocks the sun core, allowing only the corona to be visible, which will look like a bright glow around the moon. Total eclipses happen about every 12-18 months in various parts of the world, but in any particular location every 375 years!  That’s why everyone is so excited about Monday; it’s a once in a lifetime event!  For us here in Maryland, we’ll be able to see a partial solar eclipse, with the moon obscuring about 82% of the sun at the peak of the event, around 2:42 pm.

     While many are excited to view this natural phenomenon, viewing a partial solar eclipse without proper protection can lead to serious eye damage and blindness.  There is a misconception that since the sun is partially obscured, it is safe to look at it.  Not true!  The sun can damage the retina in two distinct ways.  The first is by near-infrared light which can cause thermal damage.  We can’t see infrared light and the retina doesn’t have pain receptors, so significant damage can occur undetected.  The second, and probably more common, is through phototoxicty; the retina contains many components which are oxidized by visible light, releasing reactive oxygen species and free radicals which damage surrounding tissues.  Retinal damage results in blind spots or blindness.  Burns to the surface of the eyeball can also occur, which can lead to severe pain a day later but usually doesn’t result in permanent damage.  Regular sunglasses are not effective in preventing damage; there are glasses with special filters which are available and allow safe viewing of the sun.   Be careful to wear only those that are NASA approved and that meet the international standard (ISO 12312-2).  Those numbers are usually printed on the inside of the temple of the glasses, or somewhere else that’s visible.  The following companies sell approved eclipse glasses:  Rainbow Symphony, American Paper Optics, Thousand Oaks Optical, Lunt Solar Systems and TSE 17.  Make sure you inspect the glasses to ensure there are no scratches or punctures in the filters.  Ensure kids are not peaking around the edges.

    There are other ways of viewing the eclipse safely without directly looking at the sun.  One of these is by pinhole projection.  Cross the fingers of one hand over the fingers of another, making a waffle pattern, leaving small spaces between the fingers.  With your back to the sun, you should see a grid of small partial suns in your hand’s shadow.  There are videos online of cereal viewing boxes, which are easy to make and allow viewing of an image of the eclipse inside a cereal box with your back to the sun.  http://amp.fox13news.com/news/local-news/274548581-story

    There are a lot of good websites that have more information about the eclipse; check out space.com  and the NASA site https://eclipse2017.nasa.gov/ for some more information.

    Whatever method you choose, I hope you get to take a few minutes to get outside on Monday; keep your eyes protected and enjoy the show!