Astronomers and cultures Who Paved the Way History of Astronomy Astronomers and cultures Who Paved the Way

Claudius Ptolemy Born in 100 A.D. in Egypt He was a scientist and mathematician Famous for constructing the most complete geocentric model. In it, he included the observed paths of the 5 known planets, the sun, and the moon. It was the framework for discussion about the universe for the next 1000 years.

Nicolaus Copernicus Born in 1473 in Poland He was a cleric who rediscovered Aristarchus’s heliocentric model This realization, that Earth was not the center of the universe, is now known as the Copernican Revolution The heliocentric model best explained retrograde motion

Galileo Galilei Born in 1564 in Italy He was an astronomer, physicist, mathematician, engineer, and philosopher (a Renaissance man) Widely regarded as the father of empirical science Discovered sunspots, Jupiter’s moons, and supported the idea that the Earth revolved around the sun (for which he was imprisoned for until his death)

Tycho Brahe Born in 1546 in Denmark He studied astronomy, alchemy, and medicine and late in life was the Imperial Mathematician of the Holy Roman Empire He was the last of the naked eye astronomers, making all of his observations without a telescope Mentored Johannes Kepler and passed along his decades of planetary observations to him upon his death that Kepler used to assist in his laws of planetary motion

Johannes Kepler Born in 1571 in Germany Was an astronomer, astrologer, and mathematician Worked with Tycho Brahe (his mentor) and took over as Imperial Mathematician when he died Most famous for discovering the laws of planetary motion which states that “all planets move around the sun in elliptical orbits, with the Sun as the focus.”

Charles Messier Born in 1730 in France. He was an astronomer whose primary interest was comets. He is famous for charting comets and objects confused with comets called nebulae (“stellar nurseries”) These objects are known as Messier objects and are indicated by an M. Examples: M1= Crab Nebula

William Herschel Born in 1738 in Germany He was an astronomer and a composer Famous for discovering the 7th planet Uranus, the first planet discovered with the use of a telescope

Edwin Hubble Born in 1889 in Missouri An astronomer most noted for his extragalactic (outside of the Milky Way) studies He was one of the first to note that objects which had previously been classified as nebulae were actually galaxies. His namesake telescope in low orbit is also essential to modern astronomy.

Isaac Newton Born in 1642 in England He was a physicist, mathematician, and invented a type of telescope Played an important role in developing calculus Came up with the law of gravity and the laws of motion which were used to help develop guidelines for motion in space

Maria Mitchell Born in 1818 in Nantucket, Massachusetts Was a teacher, librarian, and astronomer Became the first professional American female astronomer Discovered a comet named “Miss Mitchell’s Comet” which won her an award from the King of Denmark for her contribution to astronomy

Egyptians Egyptians used astronomy for religious, agricultural, and construction reasoning. The constellation Orion represented Osiris, who was the god of death, rebirth, and the afterlife. The Milky Way represented the sky goddess Nut giving birth to the sun god Ra.

Egyptians The Egyptian astronomers, who were actually priests, recognized that the flooding always occurred at the summer solstice, which was also when the bright star Sirius rose before the Sun. The priests were therefore able to predict the annual flooding, which made them quite powerful.

Ancient Greeks There were two different paths for thought about astronomy. Began to develop advanced astronomy by treating it as a scientific pursuit (discovery, agriculture) Philosophers such as Plato and Aristotle became fascinated with planetary movements and explanations for the universe itself

Ancient Mayans The Mayans were extraordinarily good astronomers, making observations and recording the motion of the Sun, the Moon, and the stars. *Venus was very important to them Prior to 36 B.C., they adopted a 360-day year to produce a very accurate calendar and measuring long intervals of time. The ancient Maya are also known for having the most advanced mathematics and astronomy.

Aztecs The Aztec Sun Calendar was a 360 day calendar based on astronomical readings. The calendar was three feet thick as well, so it was not small by any means and took more than 50 years to make. Aztecs are unique in their respect for the stars because they often assumed their destruction would come from above every 52 years

Stonehenge Stonehenge is perhaps one of the best known sites of ancient astronomical pursuits. It is located in Salisbury Plain, England It is an ancient stone circle from the stone age that researchers believe was a calendar or almanac. Its construction began around 2800 BC and continued until 1100 BC

Indians (Asia) Indian astronomy dates back to about 1200 BC Influenced/merged with Greek astronomy after being conquered by Alexander the Great in 3rd century BC Produced written works that contain modern accuracy including use of sundials Influenced future astronomy of other civilizations like the Chinese and the Arabs

Native Americans : The Big Horn Medicine Wheel in Wyoming is similar to Stonehenge in design It was built by the Plains Indians Its spokes align roughly with solstices and equinoxes