DAY 9: The Copernican Revolution

These flashcards cover key concepts from the lecture on the Copernican Revolution and the transition from geocentric to heliocentric models of the solar system.

Heliocentric Model

The astronomical model in which the Sun is at the center of the solar system and planets orbit around it.

Geocentric Model

The astronomical model that places the Earth at the center of the solar system with all celestial bodies orbiting around it.

Retrograde Motion

The apparent backward movement of planets relative to the background stars as observed from Earth.

Tycho Brahe

A Danish nobleman and observational astronomer known for his precise astronomical observations without telescopes.

Kepler's First Law

The orbit of each planet around the Sun is an ellipse with the Sun at one focus.

Kepler's Second Law

A planet sweeps out equal areas in equal times, meaning it travels faster when closer to the Sun.

Kepler's Third Law

More distant planets orbit the Sun at slower average speeds, expressed by the relationship p² = a³.

Phases of Venus

The varying appearances of Venus that support the heliocentric model, as it shows different phases like the Moon.

Galileo Galilei

An astronomer who supported the heliocentric model through telescope observations, including moons of Jupiter.

Observational Astronomy

The branch of astronomy that involves observing celestial objects, rather than theoretical calculations.