One of the most persistently asked questions has been: How was the universe created? Many once believed that the universe had no beginning or end and was truly infinite. Through the inception of the Big Bang theory, however, no longer could the universe be considered infinite. The universe was forced to take on the properties of a finite phenomenon, possessing a history and a beginning.

The Roman church was not the only organization to try to calculate the date of creation. In the Orthodox Church, ’Αιτος Κοσμου (‘Era of the Cosmos’) was 1 September 5509 BC; after years of rival dates, the Hebrew calendar was codified by Maimonides in 1178 and set creation at 3761 BC. 

The origin of the Big Bang theory can be credited to Edwin Hubble. Hubble made the observation that the universe is continuously expanding. He discovered that a galaxies velocity is proportional to its distance. Galaxies that are twice as far from us move twice as fast. Another consequence is that the universe is expanding in every direction. This observation means that it has taken every galaxy the same amount of time to move from a common starting position to its current position. Just as the Big Bang provided for the foundation of the universe, Hubble's observations provided for the foundation of the Big Bang theory. 

Since the Big Bang, the universe has been continuously expanding and, thus, there has been more and more distance between clusters of galaxies. This phenomenon of galaxies moving farther away from each other is known as the red shift. As light from distant galaxies approach earth there is an increase of space between earth and the galaxy, which leads to wavelengths being stretched. 

In addition to the understanding of the velocity of galaxies emanating from a single point, there is further evidence for the Big Bang. In 1964, two astronomers, Arno Penzias and Robert Wilson, in an attempt to detect microwaves from outer space, inadvertently discovered a noise of extraterrestrial origin. The noise did not seem to emanate from one location but instead, it came from all directions at once. It became obvious that what they heard was radiation from the farthest reaches of the universe which had been left over from the Big Bang. This discovery of the radioactive aftermath of the initial explosion lent much credence to the Big Bang theory. 

Even more recently, NASAs COBE satellite was able to detect cosmic microwaves emanating from the outer reaches of the universe. These microwaves were remarkably uniform which illustrated the homogeneity of the early stages of the universe. However, the satellite also discovered that as the universe began to cool and was still expanding, small fluctuations began to exist due to temperature differences. These fluctuations verified prior calculations of the possible cooling and development of the universe just fractions of a second after its creation. These fluctuations in the universe provided a more detailed description of the first moments after the Big Bang. They also helped to tell the story of the formation of galaxies which will be discussed in the next chapter.