Important events in the history of astronomy

They usually say that astronomy is one of the oldest sciences. It also mentioned that astronomers early date asiro-Babylonian era culture that flourished in Mesopotamia, about 3 to 4 000 BC Relatively recent research considers the beginning of astronomy in the mists of prehistory, the period when Cro Magnon, a true "homo sapiens", could not replace Neanderthal. It is about the year 35 000 BC, of ​​which some seem to date the bones on which were engraved the lunar phases. In fact we believe that the beginnings of astronomy are older, they being able to situate the emergence of standing are the man, which enabled him to see and observe the Heavens.

More reliable data, based on documents, we have the Age of Indo-European civilizations, particularly ancient Greek civilization. If we seek to illustrate the achievements of some illustrious names Hellenistic astronomy, we can not quote some of his great philosophers. 

-Thus, Tales of Miletus (c. VII - VI BC) was considered and skilful astronomer. Another famous name is that of Pythagoras (c. 560 - c.500 BC), which calls COSMOS sky and declares that the earth is spherical. Parmenides of Elea (c.540 - 450), after Teophrast, and he would support the theory of Earth's sphericity, would have said, as Plutarch mentions that "Moon moving around the Earth illuminates the nights with a borrowed light" .

Realistic visions and concepts and Democritus of Abdera held (460-360 BC), who not only predicted the existence of atoms, but also correctly interpreted whitish appearance of the Milky Way, the presence of numerous weak stars which the eye human can not distinguish which could be confirmed after about 2000 years ago by Galileo's first telescopic observations.

For 2000 years knowledge about the universe and the stars that populate it accumulated thanks to tireless work of scholars like Brahe, Copernicus, Galileo, Kepler, Newton, Gauss, Herschel and others so far.

 -Aristah of Samos (310-230 î.e.n.). A former student of Straton of Lampsakos and kept him to one work, the dimensions and distances of Sun and Moon which seeks to determine distances to the Moon and Sun. In terms of cosmological conception Aristah, he is assigned to Earth acceptance of combined movements.

-Hipparchus of Nicaea (c.190 - c.125 î.e.n.). It is considered the greatest Greek astronomer of antiquity. He comes from a very accurate assessment of the length of, considering it as having 365 days and a quarter without 1/300 in one day. He appreciates very accurate and synodical month period to 29 days 12 hours 44 minutes and 2.5 seconds (ending today accepted value 2.8 seconds). Another contribution of Hipparchus is compiling a catalog of stars, containing over 850 items. In this catalog he divided the stars visible to the naked eye in six classes of brightness, classification, with some refinements, has been preserved until today. Hipparchus introduced hexadecimal system, a system previously used only by the Babylonians, then the circle is divided into 360 °, each degree is composed of 60 'per minute with 60'' itself.

Claudius Ptolemy (c.90 - c.168). Outside development geocentric system that bears his name and catalog of 1025 stars that made the era, Ptolemy had other outstanding contributions: find ECVET Moon and lunar parallax calculated with enough precision.

-Nicolaus Copernicus (1473-1543). By 1512-1513, the title appears in the manuscript work of Nicholas Copernicus hypothesibus motuum coelestium to constitutis Commentariolus, best known under the abbreviated title Commentariolus (little comment), the Copernicus their setting out in a simple, non-mathematical, the main theses of heliocentrism. Copernicus's immortal opera is titled De revolutionibus orbium coelestium, Libri VI, work that was removed only in 1835, the bustle made by Galileo with his telescopic discoveries, when almost all confirmations were obtained for heliocentric theory.

-Tycho Brache (1546-1601). Determined to 51'' precession of the equinoxes a year, with final settlement "judder". He also be determined accurately at 23 ° ecliptic inclination 31 'and annual movement of sun perigee to 45'' (instead of 61''). Its catalog of 777 stars with accurate positions had an error of less than 1 '.

-Galileo Galilei (1564-1642). After 1609, when Galileo built his own several telescopes, start noticing the sky and make some discoveries of importance. First, observing the moon, lunar mountains and formations revealed characteristic, like volcanic craters or circuses. Drawing a map of the moon, quite rudimentary, Galileo calls closed areas "increase". Observing stellar fields, he discovered many new stars: the Pleiades (hen with chicken) sees 36 stars and the Milky Way, a lot of stars. Observing Jupiter, Galileo discovered the four satellites within a few days more. Galileo also seen sunspots and interpret them correctly, causing the Sun's rotation period. Home of Galileo's astronomical work is Dialogo ..., in which he compares the two world systems, Ptolemaic and Copernican at which the wrath of the clergy, who, through his inquisition initiates a process which is still famous after forced to abjure . After this abjuration legend that Galileo would be pronounced the famous phrase "E pur si move" (And yet it moves!).

-Johann Kepler (1571-1630). In 1609 the work of Kepler's Astronomia nova appears ... that set out the first two laws, of the three, known as "Kepler's laws". Act I say that "the planets move in elliptical orbits with the Sun in one focus" of the second law says that the "radius vector sweeps equal areas in equal times". In 1619 public Harmonices Mundi, the law appears to III "squares sidereal periods of revolution are proportional to the cubes large semiaxelor.". For the three laws of planetary motion, Kepler was named "legislator of heaven."

Christian Huygens (1629-1695). Discover rings of Saturn, and the brightest moon of Saturn - Titan.

-Isaac Newton (1642-1727). Newton built the first telescope mirror. In Book III of the work Philosophiae Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy), Newton analyzed the motion of the moon, planets and comets. Based on this fundamental work will be a new branch of astronomy, celestial mechanics.

-William Herschel (1738-1822). The greatest achievement was the discovery of Uranus Herschel (1781). Like achievements in the solar system we can cite the discovery of two moons of Uranus, Titania and Oberon, and rotation was abnormal, the discovery of two satellites of Saturn, Mimas and Enceladus, measuring the rotation period of Saturn and its rings, discovery Seasonal Mars and Jupiter's bands interpretation of atmosphere phenomena. He also discovered infrared radiation, determine the shape of our galaxy and found many double stars, which move around the common center of mass, obeying the law of universal gravitation.

-Urbain Le Verrier J. J. (1811-1877). Calculated location of Neptune which was discovered in 1846 by Johann Gottfried Galle. Determine exactly perihelion shift of planets.

-Clyde William Tombaugh. Discover Pluto (1930).