Topic 10 - Solar Astronomy

Question 1

Name three methods to view the Sun safely.

Answer 1

Pin-hole camera
Telescopic Projection
H-alpha filter

Question 2

List the divisions of the Sun in order, heading outwards.

Answer 2

Core, radiative zone, convective zone, photosphere, chromosphere, corona

Question 3

How hot is the Sun’s core?

Answer 3

15 000 000K

Question 4

How hot is the Sun’s radiative zone?

Answer 4

7 000 000 - 2 000 000 K

Question 5

How hot is the Sun’s convective zone?

Answer 5

2 000 000 - 5800 K

Question 6

How hot is the Sun’s photosphere?

Answer 6

5800K

Question 7

How hot is the Sun’s chromosphere?

Answer 7

5800 - 100 000 K

Question 8

How hot is the Sun’s corona?

Answer 8

100 000 - 2 000 000 K

Question 9

What happens in the Sun’s core?

Answer 9

Fusion occurs.

Question 10

What happens in the Sun’s radiative zone?

Answer 10

Energy is radiated outwards but it takes a long time because the photons collide with matter.

Question 11

What happens in the Sun’s convective zone?

Answer 11

Energy is transferred outwards through convection currents.

Question 12

How many protons are needed to produce a helium nucleus?

Answer 12

4

Question 13

How many protons are actually used to produce a helium nucleus?

Answer 13

6 are used however a helium nucleus and 2 protons are the products.

Question 14

What are sunspots?

Answer 14

Areas on the photosphere which appear darker and therefore cooler.

Question 15

What is the structure of a sunspot.

Answer 15

A central, darker, umbra with a lighter surrounding penumbra.

Question 16

How hot are sunspots?

Answer 16

The umbra is 4000K and the penumbra is 5600K

Question 17

What causes sunspots?

Answer 17

They are caused by changes in the Sun’s magnetic field. Coronal loops are ejected from the Sun and become wound up. They can then puncture the chromosphere, causing lower temperatures.

Question 18

What is the solar wind?

Answer 18

It flows outwards from the Sun and consists of protons and electrons in a state called plasma. A solar magnetic field flows with it.

Question 19

What is a geomagnetic storm?

Answer 19

A disturbance of the Earth’s magnetosphere.

Question 20

How does the solar wind affect travel?

Answer 20

• Satellites can be damaged.
• Aircraft that fly over the polar regions can lose communication systems in a Solar storm.
• Astronauts need protection

Question 21

What is the magnetosphere?

Answer 21

The interaction of the solar wind with our magnetic field.

Question 22

What are the Van Allen belts?

Answer 22

The Van Allen radiation belts are giant swaths of magnetically trapped, highly energetic charged particles that surround Earth.