GENERAL KNOWLEDGE

Detailed explanation-1: -Hubble’s law, also known as the Hubble–Lemaître law, is the observation in physical cosmology that galaxies are moving away from Earth at speeds proportional to their distance. In other words, the farther they are, the faster they are moving away from Earth.

Detailed explanation-2: -There is a phenomenon called as the redshift. Redshift happens when galaxies move away from each other, their light is more towards the red side on the visible spectrum. This redshift has been recorded when studying the position of different galaxies, and each time the redshift is observed to be even farther away.

Detailed explanation-3: -During the 1920’s and 30’s, Edwin Hubble discovered that the Universe is expanding, with galaxies moving away from each other at a velocity given by an expression known as Hubble’s Law: v = H*r.

Detailed explanation-4: -On average, the farther away a galaxy is from you, the faster it will appear to recede away from you. This shows up when you look at the colors of the stars present within the galaxy, as well as the emission and absorption lines inherent to the galaxy itself: they’ll appear to be systematically shifted towards the red.