SOLAR ECLIPSE

The solar eclipse will occur when the Moon is in between the Earth and the Sun i.e.
(1) It will be an amavasya.

(2) The Moon must be on or near Rahu or Ketu so that its latitude is near zero and the three heavenly bodies, the Moon, the Earth and the Sun, are in a line.
The reasons for a solar eclipse are the same as for lunar eclipse i.e. the Sunrays should be stopped by the dark (non-luminous) Moon from falling on the Earth. It can happen only when the Moon comes in the line of the Sun and the Earth and in between them so that the rays can be stopped. The Earth and the Sun are on the ecliptic; so, the Moon should be either on the ecliptic or very near to it i.e. the Moon should be on either of its nodes (Rahu or Ketu) or near the same.
In the case of lunar eclipse, the Moon loses light when it enters umbra and the eclipse is visible alike In the whole part of the Earth which is facing the Moon. The Moon, being much smaller than the Earth, can obstruct the Sun’s rays for a smaller area on the Earth and as such the eclipse is visible to a limited area of the Earth at a time.
Solar eclipse is of three kinds: (1) total eclipse, (li) partial eclipse and (3) annular eclipse.
In the total eclipse the whole of the Sun’s disc is not seen by the observer while in the case of a partial eclipse only a part of the Sun’s disc is covered by the Moon and as such cannot be seen.
The Moon’s angular diameter varies from 33’31” to 29’22”. The angular diameter is 29’22” when the Moon is at the greatest distance from the Earth i.e. it its apogee. The diameter is 33’31” when the Moon is nearest to the Earth i.e. at perigee. In the case of the Sun, the angular diameter of the Sun when at apogee is 31’32” and when at perigee it is 32’36”.
By the above fact it can be noticed that if at the I nne of eclipse the Moon is nearest to the Earth and l lie Sun farthest, the Moon’s apparent angular diameter will be greater than that of the Sun and it can hide the whole of Sun’s disc from the observer on the Earth in the line of the Sun and the Moon. It will be a total eclipse for that observer.
In the case of partial eclipse, only a part of the Sun’s disc will be hidden by the Moon. The reason being that the centres of the Sun and the Moon not living in an exact line with the observer i.e. when the Sun and the Moon are not exactly at Rahu or Ketu, or the observer is at a point outside the umbral cone of the Moon.
The annular solar eclipse takes place when the Sun is the nearest to the Earth and the Moon is the farthest and other conditions remain the same as that of total eclipse. It will be an annular eclipse because in this case the Moon’s apparent angular diameter is shorter than that of the Sun. The Moon’s disc will not be able to fully cover the Sun’s disc but will obscure only the central portion of the Sun. At the edges, the Sun is seen in this position in the form of a bright ring, as shown in figure 19.
The umbra created by the Moon is cone ABC when the observer is at E within umbra i.e. the Moon is the nearest and the Sun is the farthest. The observer thus can see the total solar eclipse. But when the observer is at F i.e. outside the umbra, which will happen when the Moon is the farthest from the Earth and the Sun is the nearest, he will not be observing the total eclipse and instead he will be able to see the Sun’s disc like a ring. Only the shaded portion of the Sun will be hidden by the Moon and the rest i.e. circular ring will be visible over the entire hemisphere of the Earth. Further, the track of totality can never be more than 169 miles in width and the totality can never last more than eight minutes.

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