How much do we know about the universe? Auguste Comte, a French philosopher, wrote in 1825 that all we would
ever know about the stars is that they are points of light we could never reach. However, around the same time,
Joseph von Fraunhofer determined the chemical composition of a star by analyzing its light using a prism and
spectroscope. Ian D. Bush composed a rhyme about this:
Twinkle, twinkle little star
I don’t wonder what you are
For by spectroscopic ken
I know that you are hydrogen
Redshifts for the hydrogen absorption line spectrum
From this we not only know the chemical composition of the outer fringes of a star, but, when it was discovered
that the spectral lines of most faraway light sources were shifted towards the red end of the spectrum, we
could also determine the speed of those sources relative to our observation post on Earth.
George Lemaitre proposed his idea of a universe expanding from a primeval atom as a solution of Einstein’s
general relativity formulas. He published his paper as early as 1927 . It is interesting to note that he was
an ordained priest and taught at the Catholic University of Leuven in Belgium. He was dedicated to his religion
as well as to science, becoming president of the Pontifical Academy of Sciences in 1960.
Fred Hoyle, a noted English astronomer, was the proponent of a static universe, as were Eddington, De Sitter
and Einstein. Hoyle mocked Lemaitre’s idea by giving it the pejorative name of “the Big Bang.” It was a catchy
name however, and today it is used and the theory adhered to by the established astrophysical community. In
reality the Big Bang theory explains many observations and is considered the best fitting model of our world.
It was Hubble who discovered the tool to quantify the expansion by means of the redshift of the visible
electromagnetic spectrum of stars and galaxies.