We know that the Earth is a planet in the Solar System and revolves around the Sun. Similarly the Moon is a satellite of the Earth and revolves around it. The Earth and the Moon cast long shadows in space as the Sun’s light falls on them. When the Sun, the Earth and the Moon come in one straight line and the Moon comes in between the Earth and the Sun, the Moon obscures the Sun from our view. This is solar eclipse. For people living in that particular part of the earth, it becomes almost dark. The situation in which the Sun, the Moon and the Earth come in a straight line occurs only on new moon-days. The solar eclipse, therefore, takes place only on new moon-days.
However, the solar eclipse does not take place on every new moon-day. The reason for this is that the plane of earth’s orbit makes an angle of 5° with the orbit plane of the Moon. Had their orbits been in the same plane, we would have seen solar eclipse on every new moon day. Because of this angle, the revolving moon is sometimes above and sometimes below the orbit plane of the Earth. Only sometimes they come in one straight line.
By knowing the position of the Earth, the Sun and the Moon, solar eclipse and its duration, can be predicted in advance. If the Moon obstructs the full Sun, there is total solar eclipse and if the Moon obstructs only a part of the Sun, it will be a partial solar eclipse. In total solar eclipse, the edge of the Sun is visible.
Total solar eclipses are of great importance to the scientists as, during the period of eclipse, the shining edge of the Sun and other parts can be easily studied. Solar eclipse can take place twice a year or five times at the most. During 1935 there were five solar eclipses. In 1982 four solar eclipses took place. The total solar eclipse which took place on February 16, 1980 and was seen in India lasted for a very long time.