Ans: (d)
385. The extremely luminous objects located at the centre of some distant
   galaxies and which are sources of high energy electromagnetic radiation are
   known as
   (a) Nebulae
   (b) Quasars
   (c) Meteors
   (d) Comets
Ans: (b)
386. A heavenly body similar in nature to the sun intensely hot glowing mass
   that produces its energy by thermonuclear reactions is
   (a) a planet
   (b) a meteor
   (c) a star
   (d) a comet
Ans: (c)
387. Stars twinkle because of
   (a) refraction of light from them through air
   (b) reflection
   (c) absorption
   (d) All the above
Ans: (a)
388. Meteors
   (a) look like falling stars
   (b) are really pieces of rock or metal
   (c) burn up as they shoot through the air
   (d) All the above
Ans: (d)
389. The light from the star nearest to the sun reaches the earth in
   (a) 8 minutes
   (b) 4.3 years
   (c) 12 seconds