EVERYDAY SCIENCE

Detailed explanation-1: -The velocity of the galaxy, which is also known as the redshift, is directly proportional to its distance. Hubble’s law is also known as Hubble-Lemaitre law, studied in physical cosmology. Only with the help of Hubble’s law the universe can expand and fulfil the cosmological principle.

Detailed explanation-2: -Hubble’s law, which says simply that a galaxy’s velocity (or as is sometimes plotted, its redshift) is directly proportional to its distance, also tells us something important about the state of the universe. If the universe is static and unchanging, there should be no correlation between distance and velocity.

Detailed explanation-3: -Hubble compared the distances to galaxies to their redshift and found a linear relationship. He interpreted the redshift as being caused by the receding velocity of the galaxies. The recession-distance relationship is interpreted as an overall expansion of the Universe.

Detailed explanation-4: -The more distant an object, the more it will be redshifted. Some very distant objects may emit energy in the ultraviolet or even higher energy wavelengths. As the light travels great distances and is redshifted, its wavelength may be shifted by a factor of 10.

Detailed explanation-5: -The American astronomer Edwin Powell Hubble reported in 1929 that the distant galaxies were receding from the Milky Way system, in which Earth is located, and that their redshifts increase proportionally with their increasing distance.