1.3 The Sun

Question 1

How can the sun be observed safely

Answer 1

Fitting the objective of a telescope with a h alpha filter or Mylar filter

The safest way is to use an indirect projection method in which a pinhole camera or a telescope focuses an enlarged image of the sun onto a screen which reduces the brightness level so that it is safe

Question 2

What does 1 AU mean?

Answer 2

150 million KM and it’s the distance from Earth to the sun

Question 3

What’s the Suns diameter?

Answer 3

1.4 million km

Question 4

What’s the temperature of the Suns photosphere

Answer 4

5800k

Question 5

What is the corona?

Answer 5

The outside glow of ionised gas - a faint luminous white ring

Question 6

What temperature is the corona?

Answer 6

2 million kelvins

Question 7

What’s the chromosphere

Answer 7

A gaseous layer above the photosphere

Question 8

How hot is the chromosphere

Answer 8

4600k

Question 9

What’s a sun spot?

Answer 9

Cooler areas on the photosphere that correspond to strong localised magnetic fields, these inhibit upward motion of convecting solar material and prevent it from reaching the top of photosphere resulting in lower temperatures

Question 10

What’s the umbra of a sun spot?

Answer 10

A central darker and cool region of a sun spot, about 2000k cooler than photosphere

Question 11

What’s the penumbra of a sun spot?

Answer 11

A less dark surround area of s sun spot with temperature of 200k cooler than photosphere

Question 12

What’s the Suns rotation period

Answer 12

25 days at equator, 36 at the poles

Question 13

How do we use sunspots to determine Suns rotation period

Answer 13

Observing a group of sunspots, recording there position and timing how many days it takes to return to the same position

Question 14

What’s solar maximum

Answer 14

The most active time for sunspots - when there are most sunspots, last 5.5 years where often 100 sunspots visible at s time.

Question 15

What’s solar minimum!

Answer 15

When it’s the calmest and least sunspots last first 5.5 years ones that are visible are short lived

Question 16

Where do sun spots mainly appear

Answer 16

The cycle begins with sunspots 35 to 40 degrees north or south of solar equator, eventually progress to 5-10 degrees of the solar equator

Question 17

How do we predict sunspots?

Answer 17

The solar cycle, an 11 year Chloe of the general pattern has been knows as a butterfly diagram which shows us frequency of sun spots

Question 18

How does the sun shine? (What’s thermonuclear fusion)

Answer 18

It’s the source of the sun energy, in the core of sun the temperature of 15million k is so hot hydrogen nuclei fuse together to make helium nuclei and in each fusion energy is transferred and converted and radiates to the Suns photosphere where it then radiates outwards into space

E=mc^2

Question 19

What does sun look like at different wavelengths

Answer 19

Visible light

H Alpha is a visible spectral line that’s can observe solar prominences and filaments. allows a narrow range of wavelengths either side of 657 nm to pass through

X-Ray’s are emitted form corona and allow us to understand further about Suns temperature

Question 20

How does the sun look at different wave lengths

Answer 20

Visible - how we see it

H alpha - plane with crack and a few feature

X Ray - bursting out X Ray’s looks like a fireball

Question 21

What is solar wind and what’s it like/ made of

Answer 21

A steady stream of charged particles mainly protons and electrons flowing outwards in all directions from Suns corona at speeds of 400km/s typical

The fast solar wind travels at 850km/s as it is believe to originate from coronal holes (cooler regions of corona) which allow particles to escape more easily

Question 22

What’s the sun made of?

Answer 22

Hydrogen 75%

Helium 25%

Question 23

How thick is the chromosphere?

Answer 23

2000KM

Question 24

When can you observe the chromosphere

Answer 24

Can be observed a slender/ pink ring just before totality is reached during a solar eclipse

Question 25

When can the corona be observed

Answer 25

In a solar eclipse the glowing region of ionised gas emits X Ray’s too

Question 26

What’s the temperature of central core of the sun

Answer 26

15 million K

Question 27

How fast do the solar winds travel?

Answer 27

Typical - 400km/s

Fast- 850km/

Question 28

What’s a solar prominence

Answer 28

Huge clouds of cooler gas in the Suns atmosphere

Question 29

What’s a filament

Answer 29

Same as prominence but appearing as dark silhouettes against the brighter photosphere

Question 30

What’s a solar flares

Answer 30

Sudden releases of energy