Question

A very nearby star has a parallax angle of 1 arcsec. the star is racing toward the sun. ten years later its distance to the sun has been reduced by a factor of 2 .

a. what is the new parallax angle fo the star?

b. by what factor did its apparent brightness change when the star moved to its much closer location? give a precise quantitiative answer.

Answer 1

Ans- As the distance to a star increases, the its parallax decreases.

Now, for apparent brightness change when the star moved to its much closer location-