Millions of Europeans will contemplate the sky in awe on Wednesday as a rare total solar eclipse crosses part of the continent and plunges a swathe of Spain into eerie daytime darkness.The shadow cast when the Moon blots out the Sun will begin in Russia's remote Arctic north at around 1700 GMT and continue in an arc over Greenland and Iceland.
In Spain, where the total eclipse will be best viewed, the shadow will cross the country diagonally from the northern Atlantic coast to the Mediterranean Sea, where it will vanish at around 1830 GMT.Self-described "eclipse chaser" Lucie Green was ready to watch from a boat off the Spanish island of Mallorca.
"People do get addicted to it because it is such a moving experience," the British solar physicist told AFP.Far more observers will see a partial eclipse, visible in most of Europe, Canada, the northern United States and northwest Africa.
This will be mainland Europe's first total eclipse since 2006, and more than a century since one was witnessed in mainland Spain.Spanish Science Minister Diana Morant told public radio RNE on Wednesday that it was "a Christmas Day that comes around every 100 years".
Throughout human history eclipses have stirred amazement, fear and reverence, as they appear to momentarily halt the normal course of nature.The shadow cast by the alignment of Sun and Moon creates a strange twilight during which temperatures drop, shadows appear at strange angles and some animals go to sleep.
But the phenomenon is fleeting: for observers in Spain, the total eclipse will last less than two minutes just before sunset.
In parts of Russia and Greenland it will be slightly longer, though still under two-and-a-half minutes.
The partial eclipse -- which occurs as the Moon starts and finishes crossing the Sun's path -- will last around one hour and 45 minutes.
The phenomenon will present scientists with a rare opportunity to study the Sun's atmosphere and its outermost layer, as they seek to uncover secrets about solar winds and our star's magnetic field.