What does a spectroscope have to with the big bang theory?

Answer 1

A spectroscope is an instrument that can be used to observe the frequency (or wavelength) of characteristic spectral lines to see how far the lines were shifted (red shift or blue shift) from their usual position. All galaxies outside our local galactic cluster produce light that is red-shifted; and the greater the distance between us and these outside galaxies, the greater the red shift. That the size of the red shift depends on the distance is considered isotropic (or the same in all directions), meaning the distance between our local galactic cluster and all other galactic clusters is increasing at the same ratio based on distance from us. These distant galactic clusters, demonstrating red shift, are supportive evidence that these outside galaxies are moving further apart consistent with the Big Bang Theory.

Note: The core ideas of the Big Bang is that the Universe was filled homogeneously and isotropically with an incredibly high energy density and huge temperatures and pressures and was very rapidly expanding and cooling.

Answer 2

A spectroscope can be used to analyze the light emitted or absorbed by celestial objects. In the context of the Big Bang theory, spectroscopic observations of distant galaxies reveal redshifted light due to the expansion of the universe, providing evidence for the theory's predictions. This supports the idea that the universe is expanding and supports the Big Bang theory.