GENERAL KNOWLEDGE

Detailed explanation-1: -Hubble’s brilliant observation was that the red shift of galaxies was directly proportional to the distance of the galaxy from earth. That meant that things farther away from Earth were moving away faster. In other words, the universe must be expanding. He announced his finding in 1929.

Detailed explanation-2: -Ever since 1929, when Edwin Hubble discovered that the Universe is expanding, we have known that most other galaxies are moving away from us. Light from these galaxies is shifted to longer (and this means redder) wavelengths-in other words, it is ‘red-shifted’.

Detailed explanation-3: -In one of the most famous classic papers in the annals of science, Edwin Hubble’s 1929 PNAS article on the observed relation between distance and recession velocity of galaxies-the Hubble Law-unveiled the expanding universe and forever changed our understanding of the cosmos.

Detailed explanation-4: -American astronomer Edwin Hubble and others discovered in the 1920s that the Universe is expanding by showing that most galaxies are receding from the Milky Way-and the farther away they are, the faster they are receding. The roughly constant ratio between speed and distance became known as the Hubble constant.