How does distance affect stellar parallax?

1 Answer
Dec 11, 2016

Inversely proportional to the distance.

Explanation:

The relation is parallax angle varies as the reciprocal of the

distance.

Smaller the angle, longer is the distance.

If parallax angle alphaα radian is the angle between the

directions in which the same star is observed from the same place

on the Earth in a time-gap of 1/2 year, the distance of the star is

nearly (2/alpha) AU(2α)AU.

If the star is the ( nearest to us ) Sun, the distance 1 AU=(2/alpha)

AU. So, ^alpha = 2 radian = 114.6^o114.6o, nearly. The next nearest to

us, Proxima Centauri is at a distance of 4.246 light years = 63242 X

4.246 AU= 268526 AU, nearly. This parallax angle ( measured in a

time gap of 1/2 year) will be 2/268526 radian = 0.00000745

radian = 1.5'', nearly.