Chapter 15/16: The Sun

Question 1

What is the diameter of the sun?

Answer 1

1.4 x 10^6 km (109 x Earth’s D)

Question 2

What is the mass of the sun?

Answer 2

2.0 x 10^30 kg (332,000 x Earth’s M)

Question 3

What is the surface temperature of the sun?

Answer 3

5,800 K

Question 4

What is the core temperature of the sun?

Answer 4

15,000,000 K

Question 5

What is the composition of the sun?

Answer 5

92% H and 7.8% He by nuclei (73.4% H and 25% He by mass)

Question 6

What is the Luminosity of the sun?

Answer 6

3.9 x 10^26 Watts

Question 7

What are the Layers of the sun? (inner to outer)

Answer 7

Core, Radiative Zone, Convection Zone, Photosphere, Chromosphere, Corona

Question 8

What are the layers of the Solar Atmosphere?

Answer 8

Chromosphere, Photosphere, Corona

Question 9

What is the photosphere layer?

Answer 9

It is the visible surface of the sun that we are most familiar with. (not a solid surface)

Question 10

What does the photosphere layer have?

Answer 10

Granulation, Sunspots, Prominences, Solar Flares

Question 11

What is a granulation?

Answer 11

They are blotchy spots produced by rising hot gas while the cooler gas sinks down.

Question 12

What is a sunspot?

Answer 12

A region in the photosphere where the temperature is relatively low which makes it darker than its surroundings (Umbra and Penumbra) that is associated with magnetic fields. (look like bright arcs)

Question 13

What is an Umbra?

Answer 13

The dark part of the sunspot (3,700 K)

Question 14

What is the Penumbra?

Answer 14

Slightly less dark part of the Penumbra but still darker than the photosphere layer

Question 15

What is the sunspot cycle?

Answer 15

The average number of sunspots on the sun varies but is predictable, it reaches a maximum every 11 years then falls to 0 and starts again.

Question 16

What is the butterfly diagram?

Answer 16

At the beginning of the cycle, sunspots appear far from the equator then closer as the cycle progresses

Question 17

What causes sunspots?

Answer 17

The sun rotates faster at its equator than the poles called differential rotation.

Question 18

What is a prominence?

Answer 18

It is an arc of magnetic field and solar plasma (last hours-days).

Question 19

What is a solar flare?

Answer 19

It is a sudden increase in brightness of a region of the sun, caused by the breaking and reconnecting of magnetic field lines.

Question 20

What is released in a solar flare?

Answer 20

Large amounts of energy (radiation)

Question 21

Where do solar flares usually happen?

Answer 21

Near the sun’s surface and close to sunspots.

Question 22

What is the chromosphere layer?

Answer 22

It is above the photosphere (higher temp) and gives a reddish emission line spectrum (Hydrogen).

Question 23

What does chromosphere mean?

Answer 23

place where the color comes from.

Question 24

When can you see the sun’s chromosphere?

Answer 24

During the total solar eclipse

Question 25

What is the Corona layer?

Answer 25

It is the outer layer of the sun's atmosphere.

Question 26

What is the temperature of the corona?

Answer 26

About a million degrees.

Question 27

What is the corona nearly?

Answer 27

a vacuum

Question 28

What is Solar Wind?

Answer 28

outflow of coronal gases.

Question 29

What is the heliosphere?

Answer 29

It is the sun's reach of influence on its environment.

Question 30

What is a Coronal Mass Ejection?

Answer 30

A huge blast of high energy particles then followed by vast amounts of solar plasma.

Question 31

What is an Aurorae?

Answer 31

Some solar wind particles are able to leak through the Earth's magnetic field at its weaker points (makes cool lights)

Question 32

What is the proton-proton chain?

Answer 32

A three-step process that converts hydrogen into helium to generate energy (nuclear fusion).

Question 33

What particles are in the chain?

Answer 33

Proton, Electron, Positron, Neutrino, Gamma-ray photon, deuterium, Helium-3, Helium-4

Question 34

What is the first step of the chain?

Answer 34

2 hydrogen protons turn into a neutrino, deuterium, positron

Question 35

What is the second step of the chain?

Answer 35

A hydrogen proton and deuterium turn into an isotope of Helium (2 protons one neutron (Helium-3) and gamma rays. (MUST HAPPEN TWICE)

Question 36

What is the third step of the chain?

Answer 36

Two Helium-3s turn into a Helium-4 and 2 Hydrogen protons.

Question 37

Some mass is lost and turned into the sun's energy (how much).

Answer 37

0.7% (E = mc^2)

Question 38

What is a neutrino (v)?

Answer 38

It is a weakly interacting neutral particle that travels at nearly the speed of light and has nearly no mass.

Question 39

What is Hydrostatic Equilibrium?

Answer 39

The inward gravitational force is balanced by outward gas and radiation pressure. (higher temp. = higher pressure)

Question 40

What is Radiation?

Answer 40

energy transported by photons in the Radiative Zone.

Question 41

What is Convection?

Answer 41

energy transported by mass motions of the gas in the Convection Zone)

Question 42

What energy transport is not in the sun?

Answer 42

Conduction

Question 43

How to construct a model of a star like the sun?

Answer 43

ideas of hydrostatic equilibrium, temperature, and energy transport as a set of equations.

Question 44

What is Helioseismology?

Answer 44

The sun is so dense that it is opaque - all the light we see comes from the Sun's surface. Vibration is kinda like a guitar.