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

Charles Messier Born in 1730 in France. He was an astronomer whose primary interest was comets. He is famous for cataloguing celestial objects that he thought might be confused with comets. These objects are known as Messier objects and are indicated by an M. Examples: M8, M16, and M17

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.

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

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

William Herschel Born in 1738 in Germany He was an astronomer and a composer Famous for discovering Uranus but also important was his pioneering in spectrophotometry

Johannes Kepler Born in 1571 in Germany Was an astronomer, astrologer, and mathematician Worked with Tycho Brahe and took over as Imperial Mathematician when he died Most famous for discovering the laws of planetary motion

Edwin Hubble Born in 1889 in Missouri An astronomer most noted for his extragalactic studies He was one of the first to note that objects which had previously been classified as nebulae were actually galaxies and he came up with the classification scheme that is still widely used today.

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)

Isaac Newton Born in 1642 in England He was a physicist and mathematician Played an important role in developing calculus Came up with the law of gravity and the laws of motion

Albert Einstein Born in 1879 in Germany He was a theoretical physicist Developed the special theory of relativity which he applied on a large-scale structure of the universe His general theory of relativity is crucial to modern physics E=mc2

Maria Mitchell Born in 1818 in Nantucket, Massachusetts Was a teacher, librarian, and astronomer Became the first professional American female astronomer Discovered a comet at the age of 29

Henrietta Swan Levitt Born in 1868 in Massachusetts She was a “computer” at Harvard College Observatory, where she measured and catalogued the brightness of stars She discovered a relationship between luminosity and the period of brightness of cepheid variable stars and this discovery was critical to us being able to determine the distance of faraway stars and galaxies