Questions for university level astronomy-Solar system physics topic
Describe the problems with the Geocentric model of the universe
1. The stars moved around a fixed Earth.
2. Could not explain retrofrad motion or phases of Venus.
Describe the Heliocentric model of the universe
1. Planets, including Earth, orbit the Sun.
2. Phases of Venus and retrograd motion coud be explained in this model.
Describe retrograd motion
1. Retrograde motion is when a planet appears to be moving backwards in it's orbit.
2. Copernicus reasoned that planets further away from the sun would move more slowly than closer ones. As a faster planet overtakes the Earth in their rotations, its motion against the stars, as seen from the Earth, reverses.
General facts about Sun
1. It's a star, a ball of (mainly) Hydrogen gas.
2. 700,000 km in radius.
3. Generates heat and light through nuclear fusion.
4. Surface temp. 5800K, central temp. 15 million K.
5. Hydrostatic equilibrium maintained between pressure and gravity.
Explain Hydrostatic Equilibrium
The pressure is not constant throughout a planetary atmosphere. A balance (equilibrium) is maintained between the outward pressure force and the inward gravitational force.
Hydrostatic Equilibrium equation?
T or F: The orbits of the planets are elipses and lie in, or close to the eciptic plane.
State Newton's Univeral Law of Gravitation
Gravity is a force of attraction between all matter in the universe causing apples to fall from trees and the Moon to orbit the Earth.