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# Hypatia of Alexandra

Hypatia was born in 370 BC in Alexandra Egypt and died in 415 BC
Said to be the first women astronomer.
wrote commentary on The Conics of Apollonius of Perga
thought philosophy and geometry to pagans and christians.
• Dec 6, 1043

# Romans Invade Britain

"Claudius needed a quick political fix to secure his throne. What better than a glorious military victory in Britain?" -Dr Neil Faulkner
• Aug 8, 1428

# Joan of Arc Leads French to attack the English

Joan of Arc leads French to attack the English, they were captured by Burgundians and turned over to the English
• Feb 19, 1473

# Nicolaus Copernicus

Nicolaus Copernicus was born February 19 1473 died May 24 1543.
Proposed the idea of the heliocentric universe, or the idea that the sun is the center of the universe and the Earth revolves around it. Proclaimed that the earth is only the center of gravity and center of the moon's orbit.
He also claimed that the retrograde motions of the planets and stars were only apparent, not actually happing
• Dec 14, 1546

# Tycho Brahe

Tycho Brahe was born December 14, 1546 died October 24, 1601
In 1574 he gave a course of lectures on astronomy at the University of Copenhagen.
Revolutionized the astronomical instruements.
Proved that Copernicus' heliocentric theory
• Feb 15, 1564

# Galileo Galeli

Galileo was born February 15 1564 died January 8, 1642
confirmed that the Earth orbits the sun through publication.
He discovered the moons Jupiter
He also discovered the rings of Saturn.
• Dec 27, 1571

# Johannes Kepler

Johannes Kelper was born December 27, 1571 and died November 15, 1630
Created laws of planetary motion
These laws consist of: 1) Planets move in ellipses with the Sun at one focus.
2)The radius vector describes equal areas in equal times
3)The squares of the periodic times are to each other as the cubes of the mean distances.
He was the first to explain the principles of how a telescope works
Suggested that the Sun rotates about its axis in "Astronomia Nova"
• # Giovanni Cassini

Giovanni Cassini was born June 8 1625 and died December 14 1712
first to observe the four of saturns moons.
He shares with Robert Hooke credit for the discovery of the Great Red Spot on Jupiter, Circa
Cassini was also the first to observe differential rotation within Jupiter's atmosphere.
• # Sir Isaac Newton

Sir Isaac Newton was born January 4 1643 died march 31, 1727
Founded 3 laws of physics, published under 'Philosophiae Naturalis Principia Mathematica' ('Mathematical Principles of Natural Philosophy')
Proposed the laws of gravitational motion.
• # Edmond Halley

Edmond Halley was born November 8th 1656 died January 14th 1742
Discovered, "Halleys" comet and predicted when it will show up next.
Pioneered our understanding of trade winds, tides, cartography, naval navigation, mortality tables, and stellar proper motions.
• # William Hershel

William Hershel was born November 15, 1738 and died august 25 1738
Discovered Uranus
Believed that all nebulae are clusters of stars which he called island nebulae.
He also discovered the infrared range of sunlight

• # Annie Jump Cannon

Annie Jump Cannon was born December 11, 1863 and died April 13th, 1941
Discovered over 300 stars
Created a classification system that is still in use today
classified the most stars in a lifetime; around 350,000.
• # Albert Einstein

Albert Einstein was born March 14, 1879 and died August 18 1955
Found that energy and mass are equivalent, leading to his famous formula E=mc^2
Believed that all of space and time was relative, giving us Einsteins theory of general relativity.
Discovered that the universe is forever expanding
• # Edwin Hubble

Edwin Hubble was born November 20 1889 and died September 28th 1953
found that there is a a constant relationship between galaxies' redshift and distance which helped prove that the universe is forever expanding.
Created the Hubble Sequence, which is a classification system for galaxies.
Proved that there was other galaxies outside of the milky way
• # Jan Oort

Jan Oort was born April 28, 1900 and died November 5 1992
Proved the theory of the milky way galaxy having its own rotation axis.
Found that the sun is 30,000 light years away from the center of the milky way galaxy.
Claimed that comets formed from clouds of dust that orbited the sun at a distance of one light year.
• # Karl Jansky

Karl Jansky was born October 22 1905 and died February 14 1950
Discovered radio waves coming from outside the milky way galaxy.
Named the father of radia astronomy
Built and used antennas that picked up on radio frequencies of several things that caused static. He said that he got frequencies of the radiation from the sun.
• # Carl Sagan

Carl Sagan was born November 9 1934 and died December 20 1996
Found that Venus' atmosphere is very much like Earths.
Wrote articles about life on other planets and followed this through till death
founded the seasonal changes of Mars.
• # Stephen Hawking

Stephen hawking was born January 8 1942 and is still alive today.
Founded and developed mathematical proof for black holes Hawking redefined the big bang theory, saying that they started the universe and black holes will be the end of the universe.
Published his scientifc laws of the Space-time-continium.

• # Greek Dark Ages End

Population numbers dropped
People moved in small clusters and lived pastoral lifestyles
• # Aristotle

Born in Stagira, Greece in 384 BCE and died in 322 BCE
Aristotle is know for his observations and discoveries of uniform circular motion. He found that the Earth was sphereical and believed the universe was the same way.
Aristotle also found that when one travels north or south, they will not see the same stars in the sky. Lastly and mostly known is that he though the Earth had a geocentric universe. Essentially, he thought everything revolved around the Earth
• # Hipparchus

Born in nowaday Turkey in 190 BCE and died in 120 BCE
He determined the length of a year, the amount of time it took to revolve entirely around the sun through observation.
He found that the sun and moon have epicycles
Discovered the preccession of the equinoxes