What is Stellar Parallax

Astronomers use an effect called parallax to measure distances to nearby stars. Parallax is the apparent displacement of an object because of a change in the observer's point of view. The video below describes how this effect can be observed in an everyday situation, as well as how it is seen and used for finding distances to stars.

Another way to see how this effect works is to hold your hand out in front of you and look at it with your left eye closed, then your right eye closed. Your hand will appear to move against the background.

This effect can be used to measure the distances to nearby stars. As the Earth orbits the Sun, a nearby star will appear to move against the more distant background stars. Astronomers can measure a star's position once, and then again 6 months later and calculate the apparent change in position. The star's apparent motion is called stellar parallax.

TLDR; Stellar parallax is the shift in the point of observation which later can be applied to certain trigonometry and/or calculus formulas in order to calculate the distance of a celestial body. This method has been used by humans for many years to calculate the distance of stars.

By - Jahan Shah

Last updated