Solar Eclipse Viewing Safety

by | Aug 18, 2017


Unless you live in a cave, you are aware that a full solar eclipse is occurring across a narrow band of the U.S. on Monday the 21st.  Here’s a prior IFOD on the eclipse with map and some info:

Safety Tips from NASA:

  • Looking directly at the sun is unsafe except during the brief total phase of a solar eclipse (“totality”), when the moon entirely blocks the sun’s bright face, which will happen only within the narrow path of totality.
  • The only safe way to look directly at the uneclipsed or partially eclipsed sun is through special-purpose solar filters, such as “eclipse glasses”
  • Homemade filters or ordinary sunglasses, even very dark ones, are not safe for looking at the sun; they transmit thousands of times too much sunlight.
  • Stand still and cover your eyes with your eclipse glasses or solar viewer before looking up at the bright sun. After looking at the sun, turn away and remove your filter — do not remove it while looking at the sun.
  • If you normally wear eyeglasses, keep them on. Put your eclipse glasses on over them.
  • Only use eclipse glasses which state they are compliant with the ISO 12312-2 safety standard. Note that some counterfeit glasses do say they are ISO 12312-2 compliant, so be wary of the vendor from whom you buy the glasses. Some eclipse glasses mfg sites have tips on telling real from knockoff glasses. Here’s the way you can tell real from fake glasses by one of the major manufacturers, American Paper Optics:
  • My friend and neighbor Rachel advises that Schnarr’s still has eclipse glasses

Here’s a NASA interactive map that tells when partial and full eclipse starts and ends based on exact location

Note – for those of you in the St. Louis Area – viewing just a few miles towards the maximum eclipse line can really make a big difference.  Our office in Clayton is to have about 10 sec of total eclipse while moving down to Webster Groves increases it to about 1 min 20 sec.

Monday’s current weather forecast for St. Louis area: partly cloudy.

A final note: enjoy the eclipse. Because the Moon’s orbit is increasing a few inches a year, in about 600 Million years the moon will no longer be in the right position to create a full solar eclipse on Earth.  Sad!


  1. Love the shout out John!!


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