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1000 BCE
Creation of the Universe
The Universe was created 13.8 billion years ago during the explosion titled the big bang theory. This expanded at an astonishingly high rate and temperature, doubling in size every 10-34 seconds, creating space as it rapidly inflated. The universe continues to expand. -
600 BCE
Abrahamic Universe Theory
Medieval christian, Muslim, and Jewish scholars created idea that the universe was finite. John Philiponus was the first to argue that the universe had a beginning. -
500 BCE
Atomic Universe
Democritus and Leucippus Universe made up of small,indestructible, and indivisible buliding blocks that make up everything called atoms. -
400 BCE
Aristotle
Aristotle proposes that the universe is geocentric. Earth is stationary and the universe is finite in extent but infinite in time. -
30 BCE
Stoic Universe
Greek philosophers believed that the universe is similar to a giant living body. That stars and the sun are all interconnected. -
Discovery of distant (red shifted) galaxies
Vesto Slipher was the first to discover that distant galaxies are red shifted, thus providing the first empirical basis for the expansion of the universe. -
Alexander Friedmann
Alexander Friedmann was a Russian mathematician who helped to develop models. These models explained the development of the universe. His solutions to Einstein’s field equations provided evidence of an expanding universe, and supported Big Bang theory. -
Development of the Big Bang Theory
A Belgian priest, astronomer and cosmologist named Georges Lemaître first suggested the big bang theory in the 1920s, when he theorized that the universe began from a single primordial atom. Time, space, energy and matter were then created. -
Edwin Hubble
In 1929, Edwin Hubble, an astronomer at Caltech, made a critical discovery that soon led to the discovery that the universe is expanding. -
Fritz Zwicky
Fritz Zwicky was a Swiss astronomer who was the first to hypothesize about Dark Matter. He discovered that the mass was much higher than was expected by their brightness. He concluded that much of the matter in the galaxies must be dark. -
Steady State Theory
Fred Hoyle and Hermann state that new matter is created as the universe expands. -
Cosmic Microwave Background
In 1964, US physicist Arno Penzias and radio-astronomer Robert Woodrow Wilson rediscovered the CMB as they experimented with the Holmdel Horn Antenna. They estimate its temperature of -454.765 degree Fahrenheit. This discovery contributed to the abandonment of the steady state theory. -
Cosmic Background Explorer
NASA launches the Cosmic Background Explorer to search for radiation in the universe. They mapped primordial hot and cold spots in the cosmic background radiation. These are related to the gravitational fields from the early universe. -
Dark Energy
As scientist gained a better understanding of the Big Bang Theory as well as the creation of the universe, their observations evolved with the discovery of dark energy. Dark energy is something they are unable to understand, because instead of pulling galaxies together, it pushes them apart and speeds up the separation instead of slowing it down. -
Discovery of Quasars
The discovery of Quasars supported the Big Bang theory and went against the Steady State theory. Quasars are young objects that are very luminous and active.Countering the Steady State Theory, quasars should be found all throughout the galaxy, but they are only found on the outskirts. This discovery supports the Big Bang theory in which the universe is constantly expanding.
