Modern Cosmology (ASTRON 101) - Final Review

Eratosthenes

Greek mathematician and astronomer known for calculating the circumference of the Earth by comparing the angle of the sun’s rays in two different cities

Karl Popper

Philosopher of science who argued that for a theory to be considered scientific, it must be testable and potentially capable of being proven false.

Aristarchus

Ancient Greek astronomer who proposed one of the first heliocentric models of the solar system, suggesting that the Earth revolves around the Sun.

Ptolemy

Ancient Greek mathematician and astronomer known for his geocentric model of the universe, which posited that the Earth was at the center of the universe and that all celestial bodies revolved around it. His theory is known for its epicycle component, which accounted for the retrograde motion of planets in the sky. Primary work: The Almagest

Copernicus

Renaissance astronomer who formulated a heliocentric model of the solar system, asserting that the Sun, not the Earth, is at the center, fundamentally challenging the geocentric view. Did not initially release his work out of fear of mockery from his colleagues. Primary work: De revolutionibus orbium coelestium.

Tycho Brahe

Danish astronomer known for his accurate and comprehensive astronomical observations. His work laid the foundation for Kepler's laws of planetary motion

Johannes Kepler

German mathematician and astronomer who is best known for formulating the three laws of planetary motion, which describe the orbits of planets around the Sun as elliptical rather than circular. Primary work: Astronomia Nova

Galileo Galilei

Italian astronomer and physicist known for his use of the telescope to support Copernican heliocentrism. He made significant discoveries, including the four largest moons of Jupiter, and was a key figure in the Scientific Revolution.

William Herschel

British astronomer who discovered Uranus and infrared radiation. He made significant contributions to the understanding of stellar and planetary systems.

Edwin Hubble

American astronomer who played a crucial role in establishing the field of extragalactic astronomy. He is best known for the law that relates the recessional velocity of galaxies to their distance from Earth. He provided key evidence for the expanding universe and discovered that galaxies are moving away from each other.

Alexander Friedmann

Russian cosmologist and mathematician known for his foundational work on the expanding universe and his theory that the universe is expanding.

Georges Lemaitre

Belgian priest and astronomer who proposed the Big Bang theory of the universe's origin, suggesting it began from a singular point called the “primeval atom.”

Henrietta Leavitt

American astronomer known for discovering the relationship between the luminosity and period of Cepheid variable stars, which became a crucial method for measuring astronomical distances.

Penzias and Wilson

American physicists who discovered the cosmic microwave background radiation in the 1960s.

Annie Jump Cannon

American astronomer who developed the Harvard Classification Scheme for classifying stars based on their temperatures and spectra. She was instrumental in the early study of stellar classification.

Albert Einstein

Theoretical physicist known for developing the theory of relativity, which revolutionized our understanding of space, time, and gravity. He also contributed to the development of quantum mechanics and is famous for the equation E=mc².

Gustav Kirchhoff

German physicist and chemist who made significant contributions to the understanding of spectroscopy and formulated his laws of thermal radiation. He is known for his work on blackbody radiation and the nature of light, and for outlining the three kinds of spectra.

Isaac Newton

English mathematician, physicist, astronomer, and author who is widely recognized as one of the most influential scientists of all time. He is best known for his laws of motion and universal gravitation, as well as his work in calculus and optics. Primary work: Principia