Hello All!   
      
   Solar Eclipse this Weekend   
      
   May 15, 2012: Something strange is about to happen to the shadows beneath your   
   feet.    
      
   On Sunday, May 20th, the Moon will pass in front of the sun, transforming   
   sunbeams across the Pacific side of Earth into fat crescents and thin rings of   
   light.1   
      
   It's an annular solar eclipse, in which the Moon will cover as much as 94% of   
   the sun. Hundreds of millions of people will be able to witness the event. The   
   eclipse zone stretches from southeast Asia across the Pacific Ocean to western   
   parts of North America: animated eclipse map.    
      
   http://www.youtube.com/watch?v=7YX2blo1eRk   
      
   Crescent sunbeams dapple the ground beneath a palm tree during an annular   
   eclipse in January 2010. The picture was taken by Stephan Heinsius on the   
   Indian Ocean atoll island of Ellaidhoo, Maldives. [more] [video]    
      
   In the United States, the eclipse begins around 5:30 pm PDT. For the next two   
   hours, a Moon-shaped portion of the sun will go into hiding. Greatest coverage   
   occurs around 6:30 pm PDT.    
      
   Because some of the sun is always exposed during the eclipse, ambient daylight   
   won't seem much different than usual. Instead, the event will reveal itself in   
   the shadows. Look on the ground beneath leafy trees  for crescent-shaped   
   sunbeams and rings of light.    
      
   http://spaceweather.com/eclipses/gallery_15jan10_page4.htm   
      
   A "ring of fire" over China in 2010. Near the center-line of the eclipse,   
   observers will experience something special: the "ring of fire." As the Moon   
   crosses the sun dead-center, a circular strip or annulus of sunlight will   
   completely surround the dark lunar disk. Visually, the sun has a big black   
   hole in the middle.    
      
   The "path of annularity" where this occurs is only about 200 miles wide, but   
   it stretches almost halfway around the world passing many population centers   
   en route: Tokyo, Japan; Medford, Oregon; Chico, California; Reno, Nevada;   
   Albuquerque, New Mexico, and Lubbock, Texas. In those locations the ring of   
   fire phenomenon will be visible for as much as 4 and a half minutes.    
      
   "The ring of sunlight during annularity is blindingly bright," cautions NASA's   
   leading eclipse expert Fred Espenak of the Goddard Space Flight Center. "Even   
   though most of the Sun's disk will be covered, you still need to use a solar   
   filter or some type of projection technique. A #14 welder's glass is a good   
   choice. There are also many commercially-available solar filters."    
      
   http://science.nasa.gov/media/medialibrary/2012/05/15/map_strip.jpg   
      
   The path of annularity cuts across the continental United States near sunset   
   on May 20, 2012. An interactive map is also available: click here. See also   
   the ScienceCast video.    
   Many astronomy clubs will have solar-filtered telescopes set up for public   
   viewing. Through the eyepiece of such an instrument, you can see the   
   mountainous lunar limb gliding by dark sunspots and fiery prominences. It's a   
   beautiful sight. Be absolutely sure, however, that any telescope you look   
   through is properly filtered. Magnified sunlight can cause serious eye damage   
   even during an eclipse.    
      
   A safe and fun way to observe the eclipse is to use your own body as a solar   
   projector. For example, try criss-crossing your fingers waffle-style. Rays of   
   light beaming through the gaps will have the same shape as the eclipsed sun.    
      
   Or just stand under that tree. The sight of a thousand ring-shaped sunbeams   
   swaying back and forth on a grassy lawn or sidewalk is unforgettable.    
      
   For more information about the solar eclipse, please view the ScienceCast   
   video Solar Eclipse over the USA.    
      
      
   Author:Dr. Tony Phillips| Production editor: Dr. Tony Phillips | Credit:   
   Science@NASA   
      
   More Information    
      
   Footnote: (1) It's only when sunlight passes through a small aperture that you   
   the get the "pinhole effect" necessary for solar imaging. Gaps in the leaves   
   between trees or between interwoven human fingers are perfect for this   
   purpose.    
      
   Interactive Eclipse map -- from NASA    
      
   May 20th Annular Eclipse of the Sun -- Sky & Telescope    
      
   NASA's Solar Eclipse Home Page   
      
   Details and Timetables for the May 20th annular eclipse    
      
   Annular eclipse photo gallery -- from spaceweather.com    
      
   Solar Eclipse over the USA -- ScienceCast video    
      
       
   Regards,   
      
   Roger    
   --- timEd/386 1.10.y2k+   
    * Origin: NCS BBS - Houma, LA - (1:3828/7)