Origins of Modern Astronomy and Earth's Place in the Universe

Front

What was the geocentric view of the universe?

Back

The belief that Earth was motionless at the center of the universe, with celestial bodies orbiting it.

Front

Who proposed the heliocentric model?

Back

Nicolaus Copernicus proposed the heliocentric model with the Sun at the center of the solar system.

Front

What did Ptolemy's model describe?

Back

Ptolemy's model described planets moving in circular orbits around a stationary Earth.

Front

What are the main contributions of Claudius Ptolemy?

Back

Detailed the geocentric model.

Front

What did Johannes Kepler develop?

Back

Kepler developed laws of planetary motion, establishing elliptical orbits.

Front

What is the difference between a mean solar day and a sidereal day?

Back

A mean solar day is about 24 hours, while a sidereal day is about 23 hours, 56 minutes.

Front

What is perihelion?

Back

The point in Earth's orbit when it is closest to the Sun, approximately 147 million kilometers away.

Front

What is aphelion?

Back

The point in Earth's orbit when it is farthest from the Sun, approximately 152 million kilometers away.

Front

What are the phases of the Moon?

Back

The phases include new moon, crescent, first quarter, gibbous, full moon, and waning phases.

Front

What are Milankovitch cycles?

Back

Long-term variations in Earth's orbit affecting climate and glacial periods.