Lecture 2

Question 1

What is the Big Bang Theory?

Answer 1

Prevailing model that explains the development of the universe.

Question 2

When did the Big Bang Theory occur?

Answer 2

about 14 billion years ago

Question 3

What is the notion that the universe started from a single point?

Answer 3

The Big Bang Theory

Question 4

What percent of the universe is made of hydrogen? What percent is made of helium?

Answer 4

• 75%

- 25%

Question 5

What are three points of evidence for the origin of planet Earth?

Answer 5

1) Reasonable to assume the universe has a beginning
2) Galaxies are moving away from us
3) Abundance o fHydrogen and Helium

Question 6

What is the Nebular hypothesis?

Answer 6

Bodies in solar system evolved from solar nebula

- Protosun and protoplanets formed from contracting, slowly spiralling nebula

Question 7

Where do Rocky Planets form?

Answer 7

in the inner part of the protoplanetary disk

Question 8

What do rocky planets result from?

Answer 8

Results from the coagulation of purely rock grains that form into terrestrial planets (i.e.. Earth, Mars)

Question 9

Where is the asteroid belt?

Answer 9

between mars and jupiter

Question 10

What is the star at the centre of the solar system?

Answer 10

The sun

Question 11

What is the composition of the sun?

Answer 11

mostly hydrogen, with the rest currently being helium

Question 12

How does the sun generate its heat?

Answer 12

by fusing Hydrogen into helium

Question 13

What happens when the sun has used all its hydrogen?

Answer 13

fusing helium into carbon

Question 14

When does the sun become a red giant? What will happen? -

Answer 14

• When it has used all its hydrogen, will begin fusing helium into carbon
• Consume Mercury and Venus

Question 15

What happens once all the helium in the sun is used?

Answer 15

Will begin to fuse carbon into iron, shrinking to become a white dwarf.

Question 16

What happens when all the sun’s carbon has been fused into iron?

Answer 16

A very large star will explode into a supernova

Question 17

What results from a supernova?

Answer 17

• the core of the sun would be caused into a neutron star

- for very large starts (mush larger than our sun), this would create a black hole

Question 18

How do the Earth’s layers form?

Answer 18

Chemical segregation early in the formation of Earth by gravity

Question 19

What 2 things can Earth’s layers be defined by?

Answer 19

1) Chemical composition

2) Physical properties

Question 20

Describe the core.

Answer 20

inner layer: dense, iron rich

Question 21

Describe the mantle.

Answer 21

Largest layer between core and crust composed of iron, magnesium, and oxygen-seeking elements

Question 22

Describe the crust.

Answer 22

solid, thin outer layer