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Flashcards in Lecture 1 Deck (46):
1

How does the Earth-Sun radius compare with the Sun's radius?

approx. 200 times larger

2

What is a planet?

Celestial body in orbit around the sun that is large enough to be round and clear its own orbit.

3

What is a dwarf planet?

Celestial body in orbit around the sun that is large enough to be round but hasn't cleared its own orbit and is not a satellite

4

What is a satellite?

A body orbiting a planet / dwarf planet

5

What are patterns across the whole solar system?

Orbiting the same direction, in the same plane, and with mostly circular orbits

6

What are the size differences between rocky planets versus gas giants?

Rocky planets are small, gas giants are large

7

Where are the rocky planets versus the gas giants located relative to the sun?

The rocky planets are closer to the sun, the gas giants are farther

8

What are the rocky planets made of primarily?

Metal and rock

9

What are the gas giants made of primarily?

H, He, and hydrogen compounds

10

How do the rings and moons of rocky planets compare with gas giants?

Rocky planets typically have few moons and no rings, whereas ice giants have many moons and rings.

11

Approximately how much of the solar system's mass is in the sun?

Approx. 99.8%

12

What is the sun made of?

H and He plasma / gas

13

What percentage of the angular momentum of the universe is the Sun?

Only 4%

14

What is the definition of Inertial Mass?

A quantitative measure of an objects resistance to acceleration.

15

What is the definition of gravitational mass?

Measure of the magnitude of gravitational acceleration experience by or caused by an object.

16

What is the definition of weight?

The gravitational force acting on a given body, which depends on the pull of the opposite body.

17

What is the definition of volume?

The quantity of 3 dimensional space that an object encompasses.

18

What is the formula for density?

D=M/V

19

What is Mercury's core primarily made of?

Iron

20

When would you see stars in the sky on Mercury?

Always, because there is no atmosphere.

21

What is unique about Venus's spin?

It spins the opposite direction of most other planets.

22

Does Venus have any moons?

No

23

What is surprising about Earth's moon?

It is shockingly large

24

What is Mars's terrain like?

Giant volcanoes (Olympus Mons), a huge canyon, polar caps

25

What is Jupiter mostly made of?

Hydrogen and Helium

26

What are the closest (dwarf) galaxies to us?

Large Magellanic Cloud & Small Magellanic Cloud

27

By what means is distance measured?

Redshift

28

What are Jupiter's four galilean moons?

Io, Callisto, Ganymede, Europe

29

How are Saturn and Jupiter similar?

Both large, gaseous, have rings, many moons

30

What confused Galileo about Saturn's rings?

They disappeared every few years

31

Why did Saturn's rings disappear?

They actually just became edge-on to the Earth, and are so thin that they weren't visible from Earth.

32

What is the nearest star system?

Proxima Centauri (4.2 ly)

33

How are inertial and gravitational mass related?

They are equivalent.

34

What is the formula for the volume of a sphere?

V= (4/3)pir^3

35

How large is Uranus?

Smaller than Jupiter / Saturn, much larger than Earth

36

What is unique about Uranus's axis?

It has an extreme tilt

37

What is Uranus made of?

H, He, and Hydrogen compounds

38

What kind of geysers exist on Neptune?

Nitrogen ice geysers

39

What is unique about Neptune's orbit?

It is retrograde

40

What is the name of pluto's main moon?

Charon

41

What are the three main regions of smaller solar system bodies?

The asteroid belt, kuiper belt, and oort cloud

42

1 km is how many mi?

0.621 mi

43

What is the equation relating R, D, and T?

D=RT

44

How is Luminosity calculated?

Using the stephen boltzmann law, L = SA * sigmaT^4

45

How are kinetic energy and work related?

They are equal (and both dependent on only force and distance)

46

What are the northern lights?

Charged particles from the solar wind getting trapped in magnetic fields in the atmosphere and excited by electrons