Tuesday, July 21, 2009

TOTAL SOLAR ECLIPSE 2009



















On Wednesday, 2009 July 22, a total eclipse of the Sun will be visible from within a narrow corridor that traverses half of Earth which includes most of eastern Asia, and the Pacific Ocean. The total solar eclipse of 22nd of July 2009 will be the longest eclipse of the 21st Century being 6 minutes 38 seconds at the point of maximum eclipse. The occurrences of total solar eclipses are still important, not withstanding the invention of coronagraph in 1930 and number of space instruments launched in space to make the observations of solar corona in EUV, soft X-ray and low resolution broad band images. The total solar eclipses provide minimum of scattered light about 1000 times less than that in the coronagraphs.

The total solar eclipse will be of longest duration during this century. It will be visible in India, some of the Japanese islands, China and Pacific Ocean. The eclipse begins with the sunrise in the western part of India, travels to eastern part of India, crosses to Myna-mar (Burma), small islands of Japan and China. In India Surat, Indore, Bhopal, Jabalpur, Varanasi and Patna are some of the cities lie close to the central part of the totality. In China duration of the totality will be about 5 minutes. In India altitude of the sun will be about 15 degrees in the eastern part at the time of total eclipse and this period is full of rains due to South West monsoon.



What Causes a Solar Eclipse?


An eclipse occurs at those times when the Moon moves into a position of direct alignment with the Sun and the Earth. Not all solar eclipses are total. During a partial solar eclipse, only the penumbra touches our planet. The umbra passes either just above the North Pole or just below the South Pole, completely missing the Earth. No total eclipse is visible -- only partial phases can be seen.

Why is a total solar eclipse such a rare event?


Eclipses do not occur every month during a new Moon or a full Moon. This is because the orbit of the Moon is tilted by about five degrees with respect to the Earth’s orbit, so that usually the Moon passes slightly above or below the line between the Sun and the Earth. Thus at most new and full Moons, the shadows miss their mark and no eclipse occurs.

To see a total solar eclipse, you have to be in the path of totality. With fewer than 70 total eclipses per century, the chance to see one is for most of us a once-in-a-lifetime event.

The sun's outermost region, called the corona, shines like a halo around the moon during a total solar eclipse. Such eclipses occur when a new moon passes in front of the sun. They don't happen often—only about once a year—since the tilted orbits of the sun, moon, and Earth make their alignment rare. Total solar eclipses are of special interest to astronomers because it is the only time the sun's corona can be seen from the Earth's surface.

On Wednesday, 2009 July 22, a total eclipse of the Sun will be visible from within a narrow corridor that traverses half of Earth which includes most of eastern Asia, and the Pacific Ocean. The total solar eclipse of 22nd of July 2009 will be the longest eclipse of the 21st Century being 6 minutes 38 seconds at the point of maximum eclipse. The occurrences of total solar eclipses are still important, not withstanding the invention of coronagraph in 1930 and number of space instruments launched in space to make the observations of solar corona in EUV, soft X-ray and low resolution broad band images. The total solar eclipses provide minimum of scattered light about 1000 times less than that in the coronagraphs.

The total solar eclipse will be of longest duration during this century. It will be visible in India, some of the Japanese islands, China and Pacific Ocean. The eclipse begins with the sunrise in the western part of India, travels to eastern part of India, crosses to Myna-mar (Burma), small islands of Japan and China. In India Surat, Indore, Bhopal, Jabalpur, Varanasi and Patna are some of the cities lie close to the central part of the totality. In China duration of the totality will be about 5 minutes. In India altitude of the sun will be about 15 degrees in the eastern part at the time of total eclipse and this period is full of rains due to South West monsoon.

Imaging of the solar corona has the advantages of providing the information over two dimensional region of the solar corona but it may have the small uncertainty of in the data due to variations in the sky transparency. On the other hand spectroscopy provides data only on the small portion of the solar corona but with spectral purity and is possible to account for the variations in the sky transparency. Line profiles can also yield information about the temperature and non-thermal structure of the solar corona.

Watch solar eclipse with precaution

For protecting the eyes, one must use tested solar filter goggles all through the partial phase, only during the period of totality one can enjoy the total solar eclipse with naked eyes.

3 Comments:

creativekona said...

मीनू जी ,
बहुत अच्छा तथ्यपरक लेख ...सुन्दर फोटोग्रैफ्स के साथ.
हेमंत कुमार

nvrr said...

vivid verbal description & the sequence of images projected a clear
image of solar eclipse

nagasurivenugopal said...

good..congrats