our planetary system Flashcards
1
Q
4 patterns of SS
A
- large bodies have orderly motion
- all orbit in same direction
- all spin in same direction exept venus
2
Q
definition of a planet
A
- must orbit a start
- large enough to be a sphere
- must have cleared out its orbit
3
Q
sun
A
- 99.9% mass of SS
- made of H, He
- 4 million ton mass to energy per second
4
Q
mercury
A
- rock, metal
- long tall cliffs
- hot day, cold night
- little atmosphere
5
Q
venus
A
- same size as earth
- extreme conditions due to greenhouse effect caused by CO2
- hot day and night
6
Q
mars
A
- similar size to earth
- big volcanos
- ancient water
- 2 small moons
7
Q
jupiter
A
- mostly H/He
- 300x size of earth
- 80 moons
8
Q
name the galilean moons
A
io, europa, ganymede, callisto
9
Q
saturn
A
- cool rings
- many moons
10
Q
uranus
A
- smaller tahn jupiter and saturn
- extreme axis tilt
- also moons and rings
11
Q
neptune
A
similar to uranus exept axis tilt
12
Q
2 hypotheses of SS formation
A
- solar nebula
- close encounters
13
Q
solar nebula theory
A
- SS formed from gravitational collapse of a solar nebula
- lots of evidence
14
Q
process of SS formation
A
- big gas cloud with some random spin
- it collapses under its own grav force and heats up as it does
- it spins faster
- flattens into disk
- results in flat spining disk with hot core
15
Q
how does the 2 types of planets form
A
- rocks and metals condense at hotter temps so closer to sun
- light elements condense farther out
- ice condenses very far out
rocks form within frost line
- rock planets form by rocks coliding
gas planets form by mini gas clouds
16
Q
formation of moon and water
A
collision of object into earth
17
Q
how old is the earth (and compared to universe)
A
4.5 Billion years
1/3 of universe age
18
Q
what is close encouters responsible for
A
- axis tilt of uranus
- backward spin of venus
- earths moon
- captured moon of mars
19
Q
how do we age things
A
radiometric dating
atomic decay
20
Q
A
