Key Astronomers and Their Contributions Through Centuries

Nicolaus Copernicus

Proposed the heliocentric model (planets orbit the Sun).

Johannes Kepler

Formulated the Three Laws of Planetary Motion.

Rudolphine Tables

Published in 1627, predicting planetary positions.

Galileo Galilei

Observed Jupiter's moons, Venus's phases, and sunspots.

Starry Messenger

Published in 1610, detailing observations of Jupiter's moons, the Milky Way, and sunspots.

Dialogue Concerning the Two Chief World Systems

Published in 1632, supported the heliocentric model and criticized the geocentric model.

René Descartes

Proposed plenism (universe filled with 'aether') and vortex motion for planets.

Robert Hooke

Contributed to gravity theory (pre-Newton); co-developed vacuum experiments.

Isaac Newton

Developed Calculus, Laws of Motion, and Universal Gravitation.

Reflecting Telescope

Designed by Isaac Newton in 1668.

William Herschel

Discovered Uranus (1781) and its moons Titania and Oberon.

Caroline Herschel

Discovered 8 comets and co-authored the Catalogue of Nebulae.

Nebular Hypothesis

Proposed by Immanuel Kant and Pierre-Simon Laplace for the solar system's formation.

Titius-Bode Law

Predicted planetary distances and inspired the search for Ceres and Uranus.

Friedrich Wilhelm Bessel

Measured the first stellar parallax (1838) for 61 Cygni.

Asaph Hall

Discovered Mars' moons Phobos and Deimos (1877).

Friedrich Struve & Thomas Henderson

Early contributors to measuring stellar parallax.

Percival Lowell

Popularized the idea of Martian canals.

Clyde Tombaugh

Discovered Pluto (1930) and its moons.

Henrietta Leavitt

Discovered the Period-Luminosity Relationship for Cepheid variable stars.

Harlow Shapley

Determined the location of the Milky Way's center in Sagittarius.

Cecilia Payne

Discovered that stars are mostly hydrogen and helium.

Gerard Kuiper

Predicted the existence of the Kuiper Belt.

Jan Oort

Proposed the Oort Cloud, explaining long-period comets.

Annie Jump Cannon

Developed the Harvard Classification System for stars (OBAFGKM).

De Revolutionibus Orbium Coelestium

Published by Nicolaus Copernicus in 1543, proposing the heliocentric model.

Astronomia Nova

Published by Johannes Kepler in 1609, introducing the First Two Laws of Planetary Motion.

Harmonices Mundi

Published by Johannes Kepler in 1619, introducing the Third Law of Planetary Motion.

Philosophiæ Naturalis Principia Mathematica

Published by Isaac Newton in 1687, introducing Newton's Laws of Motion and Universal Gravitation.

Catalogue of Nebulae and Clusters of Stars

Co-authored by Caroline Herschel and William Herschel in 1802, detailing star clusters and nebulae.

Observations of Mars

Documented by Giovanni Schiaparelli in 1877, leading to misunderstandings about Martian canals.