Question 15

A star is ten light years away from the earth. Suppose it brightens up suddenly today. After how much time shall we see this change?

Q. Suppose a star which is $50$ light years away from Earth explodes today. Will you be able to see the explosion in your lifetime? Give reasons for your lifetime? Give reasons for your answer.

Q. A star is $1.45parsec$ light years away. How much parallax would this star show when viewed from two locations of the earth six months apart in its orbit around the sun?

Q.

Aliens on the planet Xargon spot a distant dying star, 5 light years far. If we see the star dying today then after how much time will the star's explosion be heard by the Xargonians? (Assume Xargonians to be an immortal peace loving race) speed of sound $3\times {10}^2$ m/s

Q. The nearest star to our solar system is 4.29 light years away. How much is this distance in terms of parsecs? How much parallax would this star (named Alpha Centauri) show when viewed from two locations of the Earth six months apart in its orbit around the Sun ?

Q. A star is $8.1\times {10}^{13}km$ away from the earth. Suppose right travels at the speed of $3.0\times {10}^{5}km$ per second, how long will it take light from the star to reach the earth?