Topic 1 - Planet Earth Flashcards
1
Q
How thick is the Crust?
A
0 - 70km
2
Q
What is the Crust made of?
A
Rocks
3
Q
How thick is the Mantle?
A
2900km
4
Q
How much of the Earth does the Mantle make up?
A
80%
5
Q
How hot is the Mantle?
A
1400°C - 3000°C
6
Q
What is Skyglow?
A
- A rusty orange haze cast by lights near towns and cities
- Reduces contrast between stars and the sky
7
Q
What is Local Glare?
A
- Local light from sports grounds, car parks, street lights, security lights
- Ruins our dark adaptation
8
Q
What scale are seeing conditions measured on?
A
Antoniadi Scale
9
Q
What is twinkling (seeing conditions)?
A
Air in the atmosphere is constantly moving, which causes light to refract and change direction, which makes the star appear to twinkle
