Solar eclipses are both routine and predictable. The shadow ofthe moon streaks across the Earth about once every 18 months andastronomers can forecast its precise path centuries ahead.
But next Wednesday's total eclipse has Europe talking.
The main reason is that the eclipse path happens to cover a moredensely populated swath of the globe than any of its predecessors.There may also be a touch of millennial feeling about the last greatcelestial event of the century.
The track of totality - in which the face of the moon blots outthe whole of the sun - is just 75 miles wide. It starts out atsunrise off the coast of Nova Scotia in Canada and dashes eastwardacross the north Atlantic at 1,550 m.p.h., making landfall inCornwall, England.
The path then crosses France, Belgium, Luxembourg, Germany,Austria, Hungary, Romania, Turkey, Iran, Pakistan and India, beforedying at dusk in the Bay of Bengal. Cities covered include Plymouth,Rouen, Stuttgart, Munich, Bucharest and Karachi.
A partial eclipse, in which the moon bites away more than half thesolar surface, will be visible over all of Europe and the westernhalf of Asia.
Many people will find the partial solar eclipse boring. All theexcitement and romance comes with totality, which tens of millionswill experience.
Assuming the sky is clear, the real action begins when just a thinsliver of sun is left. The temperature will have dropped by a coupleof degrees and the wind will abate. Confused birds and animalsprepare to roost. There may be weird light effects on the ground,with the leaves of trees and bushes acting like pinhole cameras andprojecting tiny images of the crescent sun; refraction patternscalled shadow bands may race across the Earth.
In the final moments before totality, the last direct rays ofsunlight will shine through one or more lunar valleys, creating adiamond ring effect known as Bailey's beads. Then "the celestialflower opens its white petals," as eclipse specialist Francisco Diegoof University College London puts it.
The "petals" are the corona, the rarefied solar atmosphere that wecannot normally see because it is outshone by the sun. The sun iscoming into the most active phase of its 11-year cycle, so there is agood chance of seeing loops and streamers of glowing gas heading outinto space.
Although modern astronomers have sophisticated observatories forstudying the sun from Earth and space, including instruments forblotting out the solar disc and creating an artificial eclipse, somestudies of the corona are best made during an eclipse.
Americans need not feel left out entirely. Although a partialeclipse will be visible only in the extreme northeastern part of thecountry, cable television viewers will get to see the total eclipseon the Discovery Channel. It will carry live coverage from 5 to 8a.m. Wednesday Chicago time.
The last total solar eclipse in the mainland United States tookplace in 1979. The next is due Aug. 21, 2017.
Contributing: Associated Press
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