Archive for August 2011

• Posted By: tompfeiffer on Aug 25, 2011 03:05PM Category: Eruptions & current activity
  
  Eruption reader Luis Miguel Godinho directed me to the following interesting article about crepuscular rays caused by volcanic aerosols in the stratosphere at sunset:
  VOLCANIC SUNSETS:
  

  

  Sky watchers in Europe should be alert for volcanic sunsets. “For the past week, we’ve seen unusual twilight rays probably caused by high-attitude aerosols from Nabro, a volcano which erupted in Eritrea on June 13th,” reports Petr Horalek from the Ondřejov Observatory of the Astronomical Institute of the Academy of Sciences of the Czech Republic. This is how the sky looked on Aug. 23rd:
  
  “Around 20 minutes after sunset these significant crepuscular rays appeared like shining fingers in the western sky,” he describes. “The rays were so strong, I could see them almost directly overhead; and in the south, they stretched across the horizon like great red and purple stripes.”
  
  Purple is one of the telltale colors of a volcanic sunset. Fine volcanic aerosols in the stratosphere scatter blue light which, when mixed with ordinary sunset red.
  
  Source: www.spaceweather.com
  Image credit: Monika Landy-Gyebnar of Veszprem, Hungary
  

  Tags: sunset, crepuscular rays, volcanic aerosols

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  Posted By: Tom on Aug 28, 2011 11:22AM

  Similar sunsets could lately be often seen here in Athens, too.

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