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.1It'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.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.
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."
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.source: http://science.nasa.gov/science-news/science-at-nasa/2012/15may_sunday/
Get ready for spectacular 'ring of fire' solar eclipse Sunday
The moon will come between Earth and sun, casting a shadow on our planet
By Mike Wall- Font:
source: http://www.msnbc.msn.com/id/47416237/ns/technology_and_science-space/?ocid=ansmsnbc11#.T7VxguhYuVM
Sources for Solar Filters
The following is a brief list of sources for mylar and/or glass filters specifically designed for safe solar viewing with or without a telescope. The list is not meant to be exhaustive, but is simply a representative sample of sources for solar filters currently available in the United States. For additional sources, see advertisements in Astronomy and/or Sky & Telescope magazines. The inclusion of any source on this list does not imply an endorsement of that source by either of the authors or NASA.- ABELexpress - Astronomy Division, 230-Y E. Main St., Carnegie, PA 15106 - (412) 279-0672
- Celestron International, 2835 Columbia St., Torrance, CA 90503 - (310) 328-9560
- Edwin Hirsch, 29 Lakeview Dr., Tomkins Cove, NY 10986 - (914) 786-3738
- Meade Instruments Corporation, 16542 Millikan Ave., Irvine, CA 92714 - (714) 756-2291
- Orion Telescope Center, 2450 17th Ave., PO Box 1158-S, Santa Cruz, CA 95061 - (408) 464-0446
- Pocono Mountain Optics, R.R. 6, Box 6329, Moscow, PA 18444 - (717) 842-1500
- Rainbow Symphony Inc., 6860 Canby Ave. #120, Reseda, CA 91335 - (818) 708-8400 [fax (818) 708-8470] - sjdc61a@prodigy.com
- Roger W. Tuthill, Inc., 11 Tanglewood Lane, Mountainside, NJ 07092 - (908) 232-1786
- Thousand Oaks Optical, Box 5044-289, Thousand Oaks, CA 91359 - (805) 491-3642
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