GENERAL KNOWLEDGE

Detailed explanation-1: -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-2: -The Doppler red-shift of light observed from distant stars and galaxies gives evidence that the universe is expanding (moving away from a central point).

Detailed explanation-3: -The fabric of space expands. This is the cause primarily responsible for the redshifting we see of distant galaxies. Light travels through the fabric of space, which is expanding as time progresses since the Big Bang, and that expanding space stretches the wavelength of the light that travels through it.

Detailed explanation-4: -Red-shift and speed It is a result of the space between the Earth and the galaxies expanding. This expansion stretches out the light waves during their journey to us, shifting them towards the red end of the spectrum. The more red-shifted the light from a galaxy is, the faster the galaxy is moving away from Earth.