Presentation is loading. Please wait.

Presentation is loading. Please wait.

Prepare your scantron:

Similar presentations


Presentation on theme: "Prepare your scantron:"— Presentation transcript:

1 Prepare your scantron:
Use a pencil, not a pen! Fill in your name and fill the bubbles under your name. LAST NAME FIRST, First name second Put your 4-digit code instead of “IDENTIFICATION NUMBER”. --- (The last 4 digits of your OleMiss ID.) Question # 1: answer A Question # 2: answer B Question # 3: answer C Setup: Reading assignment Chapter 14 (The Sun), pp. 464–485 Please take a moment to mute your cell phone!

2 Hydrogen (mainly) gas ball
The Sun Sunspots An Average main sequence STAR Surface features: • sharp edge (photosphere) • sunspots • limb darkening (we see less deep down at the edge) Hydrogen (mainly) gas ball Hot surface (6000 C)

3 What’s inside? In core: 4 H -> He (> 1 million K)
Radiation zone: heat transfer by radiation Convection zone: by convection (“boiling”) Photosphere: visible edge (6000 C)

4 Questions coming …

5 sec 10 9 11 12 15 14 13 8 7 1 2 3 5 4 6 16 26 17 27 28 30 29 24 25 23 19 18 20 21 22 Question 4 The photosphere is A the name of all the hot parts of the Sun B the name of the visible edge of the Sun C the name of the central region of the Sun D the name of a type of camera used to photograph the Sun. E the name of a type of lens used to photograph the Sun. Next question coming …

6 sec 10 9 11 12 15 14 13 8 7 1 2 3 5 4 6 16 26 17 27 28 30 29 24 25 23 19 18 20 21 22 Question 5 How hot is the photosphere? A 600 K B 6,000 K C 60,000 K D 600,000 K E 6,000,000 K Next question coming …

7 sec 10 9 11 13 14 8 12 7 2 1 3 4 6 5 15 17 26 25 27 28 30 29 16 24 19 18 23 20 22 21 Question 6 Why is the edge of the Sun darker than the middle? A Because the photosphere is colder at the edge of the Sun than in the middle. B Because of the blurring effect of Earth’s atmosphere. C Because we see deeper down in the middle of the Sun, where it is hotter. D Because light is absorbed on the long way to the edge of the Sun. E Because the middle of the Sun is closer to us than the edge.

8 Convection zone sticking out:
granulation The Sun is “boiling”: Granules live ~ 10 min rising (hot) and sinking (“cold”) matter H image

9 Photosphere: “grainy”
Granules explained Photosphere: “grainy” Hot gas up Cold gas down

10 Sunspots Undisturbed photosphere Penumbra Umbra (6000 K) (5000 K)
“Cold spots” in the photosphere where convection is stopped by the magnetic field Penumbra (5000 K) Umbra (4000 K)


Download ppt "Prepare your scantron:"

Similar presentations


Ads by Google