Nicolaus Copernicus proposed the heliocentric model, placing the Sun at the center of the solar system, which laid the foundation for modern astronomy.

Galileo Galilei's observations with his telescope revealed the four largest moons of Jupiter, known as the Galilean moons.

Johannes Kepler's three laws of planetary motion provided a mathematical framework for understanding planetary orbits.

Isaac Newton's theory of universal gravitation revolutionized our understanding of the forces that govern the motion of objects in the universe.

Tycho Brahe's meticulous observations and data collection contributed significantly to the development of astronomy.

Johannes Kepler's observations of the variable star Mira led to the discovery of its periodic changes in brightness.

George Ellery Hale's contributions to astrophotography revolutionized the field and allowed for detailed observations of celestial objects.

Ejnar Hertzsprung and Henry Norris Russell developed the Hertzsprung-Russell diagram, which is a fundamental tool in stellar classification.

Henrietta Swan Leavitt's discovery of the period-luminosity relation for Cepheid variables revolutionized the field of stellar astronomy.

Annie Jump Cannon's work on stellar classification led to the development of the Harvard spectral classification system.

Edwin Hubble's observations of galaxies provided evidence for the expanding universe and revolutionized our understanding of cosmology.

Stephen Hawking's work on black holes, including his discovery of Hawking radiation, significantly advanced our understanding of these enigmatic objects.

George Smoot's work on the cosmic microwave background radiation provided strong evidence supporting the Big Bang theory.

Michel Mayor and Didier Queloz discovered the first extrasolar planets orbiting a Sun-like star, opening up new avenues in the search for life beyond Earth.

Sara Seager's contributions to the field of exoplanet research have led to significant advancements in our understanding of these distant worlds.