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The Big Bang theory is the prevailing cosmological model for the universe from the earliest known periods through its subsequent large-scale evolution.[1][2][3] The model accounts for the fact that the universe expanded from a very high density and high temperature state,[4][5] and offers a comprehensive explanation for a broad range of phenomena, including the abundance of light elements, the cosmic microwave background, If the known laws of phisics to form stars and galaxies.
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Bbylonians astronomers discover an 18.6-year cycle in the rising and setting of the Moon. From this they created the first almanacs – tables of the movements of the Sun, Moon and planets for the use in astrology. In 6th century BC Greece, this knowledge is used to predict eclipses.
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Thales predicts a solar eclipse.
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Plato, a Greek philosopher, founds a school (the Platonic Academy) that will influence the next 2000 years. It promotes the idea that everything in the universe moves in harmony and that the Sun, Moon, and planets move around Earth in perfect circles.
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Aristarchus of Samos proposes heliocentrism as an alternative to the Earth-centered universe. His heliocentric model places the Sun at its center, with Earth as just one planet orbiting it. However, there were only a few people who took the theory seriously.
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The earliest recorded sighting of Halley's Comet is made by Babylonian astronomers. Their records of the comet's movement allow astronomers today to predict accurately how the comet's orbit changes over the centuries.
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Anaxagoras produced a correct explanation for eclipses and then described the sun as a fiery mass larger than the Peloponnese , as well as attempting to explain rainbows and meteors . He was the first to explain that the moon shines due to reflected light from the sun.
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The renaissance came to astronomy with the work of Nicolaus Copernicus, who proposed a heliocentric system, in which the planets revolved around the Sun and not the Earth. His De revolutionibus provided a full mathematical discussion of his system, using the geometrical techniques that had been traditional in astronomy since before the time of Ptolemy. His work was later defended, expanded upon and modified by Galileo Galilei and Johannes Kepler.
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In the 19th century it was discovered that, when decomposing the light from the Sun, a multitude of spectral lines were observed (regions where there was less or no light). Experiments with hot gases showed that the same lines could be observed in the spectra of gases, specific lines corresponding to unique elements. It was proved that the chemical elements found in the Sun (chiefly hydrogen and helium) were also found on Earth.
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Hubble demonstrated that the universe was not static and Einstein's cosmological constant was not necessary. Utilizing improved telescopic devices, he was also able to confirm that those "fuzzy" objects astronomers had seen for years were in fact other galaxies.
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Most of our current knowledge was gained during the 20th century. With the help of the use of photography, fainter objects were observed. Our sun was found to be part of a galaxy made up of more than (10 billion stars). The existence of other galaxies, one of the matters of the great debate, was settled by Edwin Hubble, who identified the Andromeda nebula as a different galaxy, and many others at large distances and receding, moving away from our galaxy.
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Since 1990 our understanding of prehistoric Europeans has been radically changed by discoveries of ancient astronomical artifacts throughout Europe. The artifacts demonstrate that Neolithic and Bronze Age Europeans had a sophisticated knowledge of mathematics and astronomy.
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In the 19th century, scientists began discovering forms of light which were invisible to the naked eye: X-Rays, gamma rays, radio waves, microwaves, ultraviolet radiation, and infrared radiation. This had a major impact on astronomy, spawning the fields of infrared astronomy, radio astronomy, x-ray astronomy and finally gamma-ray astronomy. With the advent of spectroscopy it was proven that other stars were similar to our own sun, but with a range of temperatures, masses and sizes.
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American astronomer. Though it is generally believed that Gold's "steady state" theory of the universe is incorrect, he made many major contributions to our knowledge of the universe, including the nature of pulsars as rotating neutron stars, and the origin of planetary hydrocarbons.
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People are taking in account all the facts about the history of the universe to investigate more about the universe.
