ASTRONOMERS IN HISTORY

ARISTOTLE

• Greek philosopher who was taught under Pluto
• Born in 384 BC
• Died in 322 BC
• First to conclude that planets were spherical because of how perfect their formation was.
• Not having the technology we do today he concluded that the Earth rested at the center of the universe with the sun, stars, and planets revolving around it.

ARISTARCHUS

• Born in 310 - 230 BC
• He was the first person to put out the idea of the sun being the center of the universe.
• His theory was resented but in the later years of history it was confirmed to be correct.

PTOLEMY

• Greek Astronomer and mathematician
• Born AD 90
• Died AD. 168
• He believed that the Earth was the center of the universe.
• Math work was made for this flawed view of the universe and was accepted for centuries.

COPERNICUS

• Born February 19, 1473
• Died May 24, 1543
• Began the new area of astronomy when he brought back and concluded the fact that the sun was the center of the universe instead of Earth.

KEPLER

• Born December 27, 1571
• Died in 1630
• A German mathematician, astronomer, and astrologer.
• Inspired by Galileo Galilei he invented the Keplerian Telescope. An improved version of the refracting telescope.
• With this he came up with many laws of planetary motion.

GALILEO GALILEI

• Born February 15, 1564
• Died January 8, 1642
• He used a telescope to confirm the phases of Venus. Along with the discovery of the four largest satellites of Jupiter.
• He also invented an improved military compass and other instruments of astronomy.

HUBBLE

• Born November 20, 1889
• Died September 28, 1953
• American astronomer who is regarded as one of the most important observational cosmologists of the 20th century.
• Known for stating that the recessional velocity of a galaxy increases with it's distance form Earth. Which states that the universe is expanding.

ISAAC NEWTON

• Born January 4, 1643
• Died March 31, 1727
• Was an English physicist who is recognized as one of the most influential scientists of all time.
• He used Kepler's laws of planetary motion and the mathematics from it to account for the trajectories of comets and other phenomena.

GEOCENTRIC MODEL

HELIOCENTRIC MODEL