During the years 1922-1927, astronomer Edwin Hubble looking through the reflecting telescope at Mt Wilson near Los Angeles noted that the black lines on the spectrum of light from the most distant stars (galaxies) were shifted towards the red end of the spectrum. The black lines are caused by interference with light from elements in that star, the most common is hydrogen. The extent of that shift tells us the speed of the star and a doppler shift towards the blue end of the spectrum tells us that the star is coming towards us. A doppler shift towards the red end of the spectrum tells us that the star is going away from us. From his observations, Hubble was able to see that the most distant stars were all heading out into space. Based on this he presented his Expanding Universe Theory in 1927. Scientists at first ignored or rejected his theory, but it is now fully accepted. The universe is expanding and the Hubble space telescope was named in his honour.
In the above photo, white light (from Sirius) is being passed through a quartz prism. Refraction divides the light into all its spectral components with high frequency (blue light) at one end of the spectrum and low frequency (red light) at the other end of the spectrum. The black lines are caused by absorption of light by the elements from which the star is made. Hubble observed that for the most distant galaxies the black lines are doppler shifted towards the red end of the spectrum and therefor the most distant galaxies are travelling away from earth. The universe is expanding. If the universe is expanding, it stands to reason that at some time in the past, the universe had a definite beginning. Careful observations and calculations have fixed that beginning at about 13.7 billion years ago.
George Lemaitre, a Belgian astronomer became aware of Edwin Hubble’s work and in 1927 he formed the opinion that the whole universe came into existence with a huge thermo-nuclear explosion some billions of years ago. In 1948, George Gamow and Ralph Alpher published a paper called “The Origin of Chemical Elements”. This was in fact the “Hot Big Bang Theory” which is generally accepted by today’s scientists, but was not widely accepted at that time. Sir Fred Hoyle, a British Astronomer opposed Hubble’s Expanding Universe and Gamow’s “Hot Big Bang Theories and proposed instead the “Steady State Theory” in the late 1950’s and early 1960’s, but he later accepted the Big Bang. The generally accepted current scientific thinking is that in the first second of time, the energy release must have generated temperatures approaching 1032 oC. Matter such as we know it could not exist at that temperature. Only a soup of sub-atomic particles such as quarks, leptons and photons could exist at that unimaginably high temperature. As the newborn universe expanded, the particles cooled, and after about three minutes, the sub-atomic particles started to bond and form the simpler gases hydrogen and helium which abound in the universe. Did you know that the Sun is made of Hydrogen gas ? After that first flash of energy, the universe was plunged into darkness for a period of about 400 million years. During this period, the elements cooled into very large gaseous clouds, then gravity compressed the gases into liquids and solids, then the pressures at the centre became so great, spontaneous nuclear ignition occurred, the clouds lit up and became stars. Two American physicists, Bob Dicke and Jim Peebles, reasoned that if the Big Bang did occur, the great flash of light that would have been generated should still be travelling through space, but it would have experienced such a red shift that it would now exist as microwave radiation.
Then in 1965, Arno Penzias and Robert Wilson were testing a new microwave detector, when they measured strong microwave radiation from space. They quickly worked out that it was the Big Bang radiation that Dicke and Peebles had predicted. This was conclusive evidence of the Big Bang and Penzias and Wilson were awarded the Nobel Prize for Physics in 1978. Atomic bombardment at the centre of these stars generated the heavier elements such as lithium, beryllium, boron, oxygen, titanium and iron. Some of the massive stars exploded and the resulting stardust formed even heavier elements, such as are listed in the Periodic Table of Elements. It appears that all things, including you and me, are made of stardust, swept by stellar winds to their present places in the cosmos. In the first place, all the elements were hot. Some like the Sun and stars still are hot, white hot. The centre of the earth is still hot, as shown below.
Astonomers are telling us that the universe had a definite beginning. The Old Testament tells us that “In the beginning, God created the heavens and the earth.” Based on rational observations, Creation is supported by science.