Unit 2 Flashcards
What is retrograde motion?
The planets appear as if they are moving backward in the sky due to the earth passing them in its orbit.
What is the geocentric model?
An ancient way to track planet movements.
What was the telescope invented?
1600 AD
What did Galileo discover with a telescope?
- Moons mountains and valleys
- sun has sun spots
- Jupiter has moons
- the phases of Venus
What are the 3 laws of planetary motion?
- Orbits are ellipses, the sun is at one focus.
- Planets sweep out same amount of time for each phase around the sun
- P^2=a^3/Mtotal
What are tidal forces?
Tidal forces are the force of gravity causing a planet (or moon) to stretch or compress during its orbit.
How does wave motion work?
Transmits nrg without the physical transport of material.
What is frequency?
Number of wave crests that pass a given point per second.
What is a period?
One between passage of successive crests.
What is the most familiar radiation?
There all radiation.
What is black body radiation?
It is a form of thermal radiation but the particles absorb light. There is no perfect black body radiation that absorbs all light.
How can you determine the peak of the heat of a star?
The wavelength that the star put out.
What colour do the hottest stars appear
Blueish
What’s a spectroscope?
A device that splits light into component colours
What is a continuum?
Broad spectrum
