Space Science Questions and Answers – Part 2
11. How stars are formed?
Stars are formed by gravitational contraction from vast clouds of galactic gas and dust.
12.What is the density of stars?
They have a density going up to 1,000 hydrogen atoms per cubic centimetre
13. Which is the brightest star?
Sirius (Dog star)
14. Which star does not change its position in the sky?
15. How many stars are there, which are normally visible?
16. What are Super Giant Novae stars?
Super Giant Novae stars are those which are far bigger and heavier than the sun. They have very high internal temperature.
17. Why these stars are called Novae?
As the temperature is very high, these stars shrinkand explode immediately on the exhaustion of fuel. Then a new star appears to be born. Thus they emerge in space suddenly and enexpectedly.
So they are called novae or new star.
18. When did the most luminous Nova appear?
19. Which is the largest and most massive star?
The most massive star is Betelgeuse which is 300 times grater than the sun.
20.Which is the nearest star visible to naked eye?
The nearest visible star is “Alpha Centauri”