The process of measuring two angles and sides of a triangle created by the star, earth on one side, and the other side six months later is known as parallax. The parallax method is used by astronomers to determine the distance between neighbouring stars in space. An effect is used by astronomers to determine the distance to a close star. Its apparent displacement is calculated by measuring the distance between the star and the Earth.
Step-1 Look at the position of an object (a nearby star) once and then six months later.
Step 2: Determine the change in position by determining the parallax angle. There is a simple relationship between star distance and parallax.
Formula for Parallax
Here d= the distance to the star (in parsecs)
P= The parallax angle of the star (in arc seconds)
Parallax second :- A star when covering a distance of 1 arc second has equal to the 1 parallax sec(parsec). 1 parsec is equal to the 3.26 light years
Light year:- It is important to find the distance. One light year is equal to the distance travelled by light for one year.
1 degree parallax angle is equal to 3600 arc second
The sun the nearest star distance =1.2948 pc
The earth the nearest star distance =1.2948 pc
The Pluto nearest star distance =1.2948 pc
Limitation: If the star has too much distance, then parallax angle will become very small to measure and less precise the distance measurement.