Lectures 13-16 Flashcards Preview

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Flashcards in Lectures 13-16 Deck (84)
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1

How did the jovian planets form?

1.frozen hydrogen compounds (ices) formed planetesimals= build up proto-planets
2.Massive planets gravitationally attract H and He gas
3.Solar nebula less dense further out= takes longer to accumulate mass

2

Describe Jupiter's internal structure.

top-down:
gaseous hydrogen
liquid hydrogen
metallic hydrogen
core of rock, metals and hydrogen compounds

3

Does Jupiter emit more heat than it receives?

yes- also Saturn and Neptune
-probably due to continued contraction

4

Explain the red bands on Jupiter's surface.

red= lower altitude, warmer, emit more IR
white= higher altitude clouds, cooler, emit less IR

5

How does the atmosphere of Jupiter compare to the Earth's?

-similar regions: thermosphere, stratosphere, troposphere but no surface
-features persist longer as there is no friction

6

What is the Jupiter's Great Red Spot?

-giant storm, long lived, like a hurricane but high pressure

7

Can magnetic field tell us about the internal structure of a planet?

-yes

8

Why is Jupiter's magnetic field different?

-huge, interaction with IO that's basically in the magnetic field

9

What are the two categories of jovian moons?

1: formed in accretion disk around planet, larger, regular orbits, surfaces, lots of ice
2:captured- smaller, irregular shapes, little geological activity, irregular orbits

10

Is Io geologically active?

Yes, volcanoes, lot of activity due to tidal stress.

11

Why are the orbits of the Galilean moons elliptical?

because of their orbital resonances

12

Which place in the solar system is most likely to have life?

Europa. -ocean?

13

Describe the atmosphere of Titan.

Thick N2 atmosphere.
-CH4, C2H6 give greenhouse effect
-organic molecules
-lakes of liquid methane and ethane
-similar geology to Earth

14

Do all jovian planets have rings?

Yes.

15

How thick and how wide are Saturn's rings?

10 m thick
140 000 km wide

16

What causes the bands in the rings?

Bigger objects sweeping it gravitationally.

17

A very bright ring will be denser or less dense?

denser

18

What are asteroids?

Rocky leftovers of planet formation.
-small more common than big ones

19

What is the name of the largest asteroid and how big is it?

Ceres
1000km in diameter

20

Would all the asteroids in the solar system add up to a planet?

No, not even a terrestrial one.

21

What are the physical characteristics of asteroids?

Not round, cratered

22

Describe asteroid orbits.

Most asteroids in the asteroid belt between Mars and Jupiter.
Trojan asteroids= follow Jupiter's orbit

23

How do we call asteroids that cross Earth's orbit?

near earth asteroids

24

How does Jupiter influence the asteroid belt?

Asteroids in orbital resonance with Jupiter experience periodic gravitational tugs.
=this creates gaps in the asteroid belt
-tidal forces from Jupiter prevented a planet forming

25

What is a meteorite?

A rock from space that falls through Earth's atmosphere.

26

What is a meteor?

The bright trail left by a meteorite.

27

Describe a comet.

-icy counterpart of an asteroid
-nucleus is a dirty snowball
-most comets remain in deep freeze in the outer solar system
-comets have a tail only when they get close to the Sun and start melting

28

What is a coma in a comet?

The atmosphere that comes from a comet's heated nucleus.

29

What is a plasma tail?

Gas escaping from coma, pushed by solar wind.

30

What is a dust tail?

Pushed by photons. always facing away from the Sun.