408 b.c - 347 b.c

Eudoxus was a Greek astronomer who studied under the impression of Plato and taught Aristotle. He developed the first geometric model of celestial movement. Eudoxus was also a mathmatician who introduced proportions. As an Astronomer Eudoxus believed the phases of the stars caused the weather.


190 b.c - 120 b.c

Hipparchus was born in Nicaea,Bithynia which is now known as Iznik, Turkey. Hipparchus was one of the closest Astronomers to guess what we have determined to be the langth of a year and he was only off by about six and a half minutes. In his days Hipparchus catalogued around eight-hundred fifty stars. He also discovered the precession of Equinoxes as 46" altough the moderen day number is 50.26" it is much closer than the theroy of Ptolemy who tought it to be around 36".


100 a.d - 168 a.d

Ptolemy introduced the idea that the Earth was the center of the universe and that the Sun, Moon ,and all other celestial bodies reveolved around it. Ptolemy's major Astroligical text was titled Tetrabiblos Syntaxis which means four books. He recorded one-thousand stars and three-hundred were newly found. He also wrote the Almagest which was an astronomical treatise that is text on the ancient view of Astronomy. He calculated the circumfrence of the Earth and belieeved that the Earth was indeed round.


1473 a.d - 1543 a.d

Copernicus unlike Ptolemy thought that the sun was the center of the universe this theroy is now known as the Heliocentric theroy. One of Copernicus's most famous books about astronomy was De Hypthesibus Motuum Coelestium a se Censtitutis Commentariolus which is now more commonly known as Commentariolus.


1546 - 1601

Brahe became famous when he created precise astronomical measurements of the solar systemand about seven-hundred stars. Brahe discovered a supernova near the constellation Cassiopeia. Frederick II who was the king of Denmark and Norway gave Brahe funds to build a observatory which was completed in 1576 which is now known as the castel of Uranienborg.


1564 - 1642

Galileo invented the telescope and used it to prove the Copernican theroy. Galileo was called out twice by the church for his astrological belief that the sun was the center of the universe. Hedeveloped the universal law of acceleration. Galileo discovered craters on the moon, stars in the milky way. He also discovered four satilites orbiting Jupiter, and the phases of Venus.


1643 - 1727

Newton discovered and established the three universal laws of motion by tying together his discovories with that of Kepler`s three laws of planetary motion. Newton was as many great astronmers were a mathmitician he came up with the Binomial Theorem and was one of the two creators of calculus.


1738 - 1822

Herschel was the first person to discover a planet since antiquity and discovered the planet Uranus in 1781. He also discovered that when sunlight passed through different color filters the temperatures seem to have different amounts of heat. Herschel and his sister Caroline constructed many telescopes and discovered many double stars and nebulae.