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Q1. What is a Sun?
It is a Star.

Q2. What comprises of a Sun?
71% Hydrogen; 26.5% Helium; and 2.5% other gases.
Q3. What is the outside temperature of the Sun?
6000 Degree Celcius (about 5800 degree Kelvin)
Q4. What is the inside temperature of the Sun?
About 1,50,00,000 degree Celsius.
Q5. How far is the Sun from the Earth?
Average distance from the Earth is about 14,95,98,600 Kms.
Q6. What is the approximate age of the Sun?
5 Billion years.
Q7. What is the rotation period of Sun?
25 days 9 Hrs 7 Minutes.
Q8. How much time does the rays of the Sun take to reach the Earth?
49.9 Seconds.
Q9. How much time does the light of the Sun take to reach the Earth?
8 Minutes and 16.6 seconds.
Q10. How the glowing and radiating surface of the Sun is called?
Q11. How the reddish coloured area above the photosphere is called?
Q12. When is the Chromosphere visible to the naked eye?
During Total Solar Eclipse.
Q13. What is "Corona"?
The Halo gas around Sun and above the Chromosphere is known so.It is visible only during Total Solar Eclipse.
Q14. What is the main composition of the Sun?
Hydrogen 71%
Q15. What are the constituent colors of Sun Light?
WHITE - broken up into it's seven constituent colors called VIBGYOR.Representing Violet, Indigo, Blue, Green, Yellow, Orange and Red - the first letters making up the VIBGYOR.
Q16. What constitute a Cosmic Year?
Sun's single revolution around the gallactic centre at 285 Kms per second takes 224 million years to complete. This period is called a Cosmic Year.
Q17. What kind of process takes place at the centre of the Sun?
Sun has a giant furnace at the centre where Hydrogen gets converted to Helium at the rate of around 600 million tonnes per second.
Q18. What is radiation of the Sun?
The energy released from the core of the Sun, in the process of conversion of Hydrogen to Helium is called radiation. Thes seaps in the form of X rays and heats the surrounding medium.
Q19. What are Cosmic rays?
Atomic particles from space which travel close to the speed of light. They are Protons, the nuclei of Hydrogen atoms.
Q20. What are Primary Cosmic rays?
The rays direct from outerspace which would destroy or deform cells in living organisms. Earth's atmosphere acts as a shield of protection.
Q21. What are "Sun Spots"?
Patches of gas cooler than gases around them. Average life is two to three weeks. The highest recorded life of a sunspot is 8 months.
Q22. What is a "Sun Flare"?
The collapse of the magnetic fluid around a sunspot causing an explosion or eruption of energy in the Sun's atmosphere, is called so. The explosion is equivalent to millions of Hydrogen bombs.
Q23. What is a "Mid Night Sun"?
About mid summer, in the polar regions, the Sun remains above the horizon atleast partially throughout 24 hours. The Sun is therefore, visible particularly at midnight and hence is called "Midnight Sun". This phenomenon can be seen at Norway.