Sun is a ball of hot gases mainly composed of hydrogen and helium with many other gases.
It is the nearest star which continuously emits enormous amounts of heat and light. The Sun is the main source of energy on Earth. Our Sun provides heat and light for all the planets in the solar system. The Sun is at a distance of approximately \(150,000,000\ km\) from the Earth. The age of our Sun is estimated to be \(4.5\) billion years old.
View of Sun from Earth
Position of the rising Sun:
Uttarayan and Dakshinayan:
The shifting of the Sun towards the south is called as 'Dakshinayan'. This shifting starts from \(21\ June\), which is known as the winter solstice.
The shifting of the Sun towards the north is called as 'Uttarayan'. This shifting starts from \(22\ December\), which is known as the summer solstice.
Uttarayan and Dakshinayan positions
- A place is chosen in such a way that the eastern horizon is visible.
- The rising Sun's position is marked by selecting a tree or an electric pole as a marker.
- Now, the direction of the rising Sun is noted once every week.
- If this observation is taken every week, it is noted that the point of sunrise changes continuously.
- There is a gradual shift in sunrise towards the south from the summer solstice (around \(21\ June\)). After this point, the Sun is said to be in 'Dakshinayan'. This shifting continues till the winter solstice, which is on \(22\ December\).
- From then, the point of sunrise changes towards the north from the direction of the south. The change in the point of sunrise is said to be 'Uttarayan'.
- From the equator, only on two days of the equinoxes (around \(21\ March\) and \(23\ September\)), the Sun rises in the east.
Except for these two days, the Sun rises either in the north of east or south of east. Thus, the direction of the rising Sun does not determine the directions correctly, but the Pole Star is a good indicator of directions.