Solar eclipses occur when the Sun, Moon and Earth are perfectly aligned.
It was when our moon is on the ecliptic plane that comes between the Earth and the Sun for giving us this wonderful show.
Partial eclipses occur then 2 times per year.
On August 11, 1999 at 9:30 (UTC), a total solar eclipse began in the Atlantic Ocean and traveled a thin part of Europe (France, Belgium, Luxembourg, Austria, Hungary, Romania, Bulgaria) continued his run towards Asia (Turkey, Iran, Pakistan, India) to expire at 14:36 in the Bay of Bengal.
A total eclipse occurs roughly every 18 months. But it needed to see her travel the world. The diameter of the Moon is 3 474.6 kilometers, the Sun, 1 392 000 km. The report is about 1/400ème.
The mean distance from the Sun from Earth is about 150 million km. The mean distance of the Moon from Earth is about 375 000 km.
The report is about 1/400ème. It thus appears as the same size, this explains the perfect eclipse of the sun for a few seconds, by the moon during a total eclipse.
The cone of shadow of the eclipse affects a band 110 km wide around on the ground floor.
In the center of this band, called the line of centrality, the total phase will be the longest, about 2 minutes 30 seconds.
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Baily grains are not visible on an eclipse of the moon, but during a solar eclipse by the Moon. During an annular eclipse of the sun can observe this phenomenon called the Baily beads.
This phenomenon is due to the topography of the surface of the moon (presence of mountains, craters, valleys,...).
It has been vividly described by Francis Baily, who noted this phenomenon in 1836.
These abrasions of the Moon by sunlight during a solar eclipse, allows beads of sunlight to shine in places and not others. We know perfectly the profile irregularities and lunar astronomers can calculate in advance the appearance of beads on the eclipse.
The beads Baily appear briefly for a few seconds on the path of the eclipse.
Their duration is near the edges of 1 to 2 minutes. The Red Flash, appears just after the vision of grains Baily. This passage very short bright pink color of the solar corona. The red color is due to the alpha line of hydrogen which radiates in the wavelength.
The diamond ring or diamond Airy, is the last portion of the sun silhouetted behind the black disk of the moon. At this moment, this image looks like a ring with a diamond its brilliance of a thousand lights. It takes place just before or just after the eclipse.
Image: Total Eclipse of the Moon, we can see the beads Baily, flash red, diamond ring or diamond Airy, the Sun's chromosphere embellished coronal jets.
The annular eclipse or ring of fire
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The ring of fire is the name given to an annular eclipse of the Sun by the Moon.
At maximum eclipse, the center of the sun disappears and the dark moon is surrounded by a blinding sun.
The actual diameter of the Moon is 3 474.6 kilometers, plus or minus 0.06 km, its height is 405 500 km and perigee at 363 300 km. It is when the Moon is farthest from Earth that annular eclipses occur since the apparent diameter of the moon, while smaller does not cover the Sun's apparent diameter, as in the spectacular image below cons.
Image: here, a spectacular annular eclipse taken in January 1992.
credit & Copyright: Dennis L. Mammana