observing the solar system. greek observations greek astronomers believed earth to be the center of...
TRANSCRIPT
Observing the Solar System
Greek Observations• Greek astronomers believed Earth to be the
center of the universe. This is known as a geocentric system.
The Copernican Revolution
• Copernicus thought that the sun is at the center of the system of planets. This system is called a heliocentric system.
Galileo's Evidence
• Galileo Galilei used the newly invented telescope to make discoveries that supported the heliocentric model.– Galileo saw 4 moons revolving around Jupiter,
proving not everything revolves around Earth.– Galileo saw Venus go through a series of
phases, which wouldn’t happen if it only circled around Earth.
Kepler’s Calculations
• Kepler, who was once the assistant to a successful astronomer that died before their research was complete, had concluded from his calculations that the orbit of each planet is an ellipse instead of a perfect circle.
Modern Discoveries
• Since Galileo’s time, we have discovered Uranus, Neptune, and Pluto (which is no longer a planet).
• Today we know that the solar system consists of the sun, the planets and their moons, and several kinds of smaller objects that revolves around the sun.