Unit 6 Space Science B "Exceeds"

Question 1

Describe the basic structure of the Milky Way galaxy and the general position of the Earth within it.

Answer 1

The Milky Way is a spiral galaxy with a bulge of stars at the center and a disk of spiral arms extending outward like a pinwheel. The Earth is located in a spiral arm of the Milky Way galaxy about two thirds of the way from the center.

Question 2

Describe the two main pieces of evidence that support the big bang theory.

Answer 2

1. The existence of cosmic microwave background radiation in every direction is evidence of the energy produced during the big bang.
2. The red shift in the spectra of distant galaxies shows that the universe is expanding.

Question 3

What is a nebula?

Answer 3

A nebula is a large cloud of gas and dust spread out over a large volume of space.

Question 4

What is accretion?

Answer 4

Accretion is the process when small particles collide and stick together to form larger objects in space due to gravity.

Question 5

Describe the major steps in the formation of our solar system according to the nebular theory?

Answer 5

1. The solar nebula is formed from a cloud of dust and gas left over from exploded stars.
2. Gravity pulled these small particles together causing the nebula to contract and rotate.
3. As the nebula contracted, it began to spin faster and flatten out to form a protoplanetary disk.
4. The sun formed as fusion began at the center of the disk.
5. Dust grains collided and grew larger to form asteroid-sized planetesimals.
6. Planetesimals grew by accretion forming moon-sized protoplanets.
7. The protoplanets combined to form the planets.

Question 6

Identify the main factor that determines the path of a star’s evolution and most of its characteristics.

Answer 6

The mass of a star determines the path of its evolution and most of its characteristics.

Question 7

Create a flowchart showing the evolution of stars.

Answer 7

Please see rubric for complete flowchart.