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Flashcards in Lecture 5 Deck (42):
1

Which moon was found to have water plumes?

Europe

2

What does Europa's geology look like?

Saltwater ocean under a crust of ice

3

How are scientists planning on observing Europa's plumes?

By taking photos during Europa's transit across Jupiter so that the plumes are backlit.

4

What are the three pieces of tech that a mission to Europa would carry?

A UV Spectrometer, a mass spec, and a dust analyzer

5

What is a another moon that exhibits the behaviour of Europa?

Enceladus

6

What did the ancients think the sun was made of?

Burning coal

7

What did pre-modern scientists think kept the sun warM?

Gravitational contraction

8

Who discovered radioactive decay?

Becquerel, Rutherford, the Curies

9

What is radioactive decay?

Energy (in the form of alpha, beta, and gamma particles) given off by the nucleus

10

What keeps the sun burning?

Nuclear Fusion!

11

How does the sun keep from collapsing in on itself?

It has a gravitational equilibrium

12

What is gravitational equilibrium?

The gravity pulls in just enough that the outward rush of gas is held back, so the sun maintains its shape.

13

What is needed for fusion to occur?

Extremely high temperatures, an electromagnetic force and quantum tunneling.

14

How did gravitational contraction contribute to nuclear fusion?

It provided the heat necessary as the sun was FORMING

15

How many protons are necessary for fusion of 1 He to occur?

4 protons

16

What else is expelled through fusion?

2 gamma rays, 2 positrons, 2 neutrinos, energy

17

How does the virial theorem work?

As energy is used to push a satellite further out of orbit, the satellite orbits slower

18

How does virial theorem apply to the sun (solar thermostat)?

As nuclear fusion heats and speeds up, the sun expands and cools, slowing the fusion down; ad infinitum

19

How does convection affect photos?

It allows them to reach the surface faster

20

How are kinetic and potential energy related?

Etotal=Ekin + Epot

21

How are total energy and potential energy related?

Etotal=1/2Epot

22

What are the three methods we can use to know what goes on inside the sun?

Mathematical models, observing solar vibrations, observing solar neutrinos

23

Approximately how long is the sun's spin?

about a month

24

What is the outermost aspect of the sun's structure?

the solar wind

25

What is solar wind?

Charged particles escaping

26

What is layer is just below the solar wind and above the chromosphere?

The Corona

27

What is the corona?

It is the super hot, low density outer layer of the sun that emits x-rays

28

What is the layer that is just below the corona but above the photosphere?

the chromosphere

29

What is the chromosphere?

Slightly cooler than the corona, it emits alpha particles and UV radiation

30

What is the layer below the chromosphere and above the convection zone?

It is the photosphere

31

What is the photosphere?

It is what we see as a "surface", and it is the origin of most photos

32

What is the layer below the photosphere but above the radiation zone?

The convection zone

33

What is the convection zone?

The area where hot gas rises and cool gas falls

34

What is the layer below the convection zone but above the core?

The radiation zone

35

What is the radiation zone?

The zone where energy moves outward as photons

36

What is the innermost layer?

the core

37

What is the core?

the hottest area where fusion occurs

38

What are the conditions of a sunspot?

A cooler spot where the magnetic field is twisted

39

What is the zeeman effect?

Used to measure sunspots, the zeeman effect shows how spectral lines are split in areas that are sunspots because of the magnetic fields

40

What causes prominences or filaments?

Magnetic field lines gone awry

41

Why does the corona not appear always uniform?

It only appears where magnetic fields trap hot gas

42

What are coronal mass ejections?

Bursts of charged energetic particles