Question

Explain the parallax method for measuring the distance of a near star.

Answer 1

Definition of the Parallax method.

The parallax method is a method of measuring the two angles and sides of a triangle formed by a star six months later, the Earth on one side, and the Earth on the other. Astronomers use parallax to find the distance between adjacent stars in the universe.

Explanation.

Step-1 Look at the position of an object (closer star) once and then again after six months.

Step-2 Evaluate the variation in position by finding the angle of the parallax.

There is a simple relation between star distance and its parallax.
Parallax Formula is given as,
$d=\frac{1}{P}$
where,

$d$ is the distance to the star (in parsecs).
$P$ is The parallax angle of the star (in arc seconds).
Parallax second:- A star when traveling a distance of 1 arc-second is equal to the 1 parallax sec(parsec).
1 parsec is equal to the 3.26 light-years.