What is constellation?

A constellation is defined as a group of stars that forms a recognizable shape or pattern in the night sky [1]. While these stars appear to be in the same plane or at the same distance when viewed from Earth, this is an optical illusion. In reality, the stars within a constellation are distributed in three-dimensional space and are located at vastly different distances from Earth. For instance, in the constellation Cygnus, the faintest star is actually the closest, while the brightest is the farthest. Some stars in a pattern like the Big Dipper may be tens of thousands of light-years further away than others in the same group. Therefore, constellations are patterns of stars that are not equidistant from Earth. While the term 'satellite constellation' exists for artificial satellites, it refers to a coordinated system for global coverage rather than the traditional astronomical definition [2].

Sources

1. [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 1: The Universe, The Big Bang Theory, Galaxies & Stellar Evolution > 1.6. Constellations > p. 15
2. [2] https://en.wikipedia.org/wiki/Satellite_constellation