Unit Nine - Astronomy - Actual Motions Flashcards
What is the Heliocentric model?
The sun is at the center of the solar system
Definition of Rotation
Earth spinning on its axis
Definition of Period of Rotation
Amount of time to make one complete rotation
What is Earth’s Period of Rotation
24 hours
How many degrees is Earth’s tilted axis?
23.5
What are the two pieces of evidence that proves that the Earth is rotated?
- Foucault Pendulum
- Coriolis Effect
What is the Foucault Pendulum?
When allowed to swing freely, a large pendulum can change it’s path due to Earth’s rotation
Definition of Revolution
The motion of one body around another in orbit
What is the Period of Revolution?
The amount of time required to orbit the Sun one time
What is evidence of the Earth’s revolution?
Parallelism of Earth’s Axis
Definition of Parallelism of Earth’s Axis
Earth’s tilted axis (23.5) is always pointed to the same location in the sky, giving us our different seasons.
How do different times in the year affect where the sun rises?
Equinox - Sun rises directly east to west
June 21st - Sun rises northeast to northwest
December 21st - Sun rises southeast to southwest
Definition of Ellipse
The oval shape of a planet’s orbits
Definition of Eccentricity
The degree of flatness or “ovalness” of an ellipse
What is the eccentricity of a perfect circle?
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