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Unexplored universe fascinated mankind for millennia. Almost all mythologies raised issues of cosmogony, and so the history of the creation of the universe. Ancient scientists created its astronomical, mostly geocentric, models. In ancient Greece there already were heliocentric concepts developed later in the Middle Ages by Nicholas Copernicus, confirmed by Galileo, supplemented by Thomas Digges and Giordano Bruno, and finally accepted by other scientists.

Copernican concepts were challenged by many other researchers. One of them was Tycho Brahe, a Danish astronomer who, despite denying the heliocentric theory, carried out a number of important observations. Many researchers who lived after him referred to these observations. Brahe was also a creator of the first astronomical instruments of the pre-telescope era. Thanks to Tycho Brahe?s accurate measurements, his pupil, Johannes Kepler, discovered patterns in planetary motions (Kepler's laws), which partially confirmed the assumptions of the Copernican theory.

Isaac Newton demonstrated that the same laws govern the motion of bodies on Earth and the movement of celestial bodies giving more proof to the heliocentric theory. He gave mathematical reasoning for Kepler's laws and even expanded them, proving that not only the orbits are elliptical, but may also be parabolic.

Einstein's general theory of relativity is the base of contemporary models of the universe. Einstein's spent his life working on the unified field theory which was supposed to easily explain the principles and operation of the universe. Published in 1916 the theory of gravitation was not only a breakthrough in the research nature of the universe, but it also revolutionized other sciences. But even Einstein was not infallible. He initially introduced a so called cosmological constant to his field equation which was independent of time and space and was supposed to prove that the universe is static. The discovery of the expansion of the universe questioned the existence of this constant and Einstein called adding it to the equation the biggest mistake of his life.

Information about Cosmos provided by Edwin Hubble who discovered and proved the truth of the red shift phenomena and the expansion of the universe were crucial to the development of cosmology. Red shift is the change of an electromagnetic wavelength happening between emission and observation. This concept has been since associated with the change in the position of spectral lines in the electromagnetic spectrum of distant astronomical objects. This repositioning involves a proportional shift of the entire spectrum in the direction of longer waves, which in the case of light waves means a shift towards the red part of the spectrum. This shift is proportional to the distance of an object from Earth and constitutes the basic argument for the model of an expanding universe. Hubble's discovery gave rise to the emergence of a series of hypotheses, which then led to the creation of the Big Bang Theory.

In 1947, a prominent U.S. physicist and cosmologist of Russian origin, George Gamow, developed the hypothesis of a hot early Universe; currently the most likely hypothesis of the creation of Cosmos, commonly called the Big Bang Theory. The cosmic microwave relict radiation (afterglow radiation left over from the hot Big Bang), discovered in 1964-1965 by Arna Penzias and Robert W. Wilson proves the validity of this theory.

Currently, one of the most prominent researchers of Cosmos is Stephen William Hawking, a British scientist and professor at the California Institute of Technology in Pasadena and the University of Cambridge where, until recently, he held the post of Lucasian Professor of Mathematics, as Newton did once. This astrophysicist has a neuro-muscular dystrophy that is related to amyotrophic lateral sclerosis, a condition that has progressed over the years and has left him almost completely paralysed. He is on a wheelchair and communicates verbally through a speech synthesizer. At the end of 70s Hawking postulated that black holes lose mass as a result of particle-antiparticle pairs appearing on both sides of their event horizon at the expense of their gravitational field energy. So far, Hawking radiation is a hypothesis. Recently, however, Stephen Hawking renounced his claim that matter which falls into a black hole never comes out. Hawking is a well known public figure and an author of popular science books, "A Brief History of Time" and "The Universe in a Nutshell." He made guest appearances in several television series (like "Star Trek", "Simpsons") and lent his voice to Pink Floyd and a cover version of Michael Jackson song.