Ch. 21

Question 1

Star Birth

Answer 1

From dense, cool clumps or separated hotter clumps

Question 2

Protostars

Answer 2

Very young stars gathered from dust & gas + contracting under gravity

Question 3

Orion Nebula

Answer 3

• Can best be seen with infrared images

- 4 bright stars in center: Trapezium stars

Question 4

Star Formation

Answer 4

(1) Dense cores form within molecular cloud
(2) Protostar forms at center of dense core accumulating add’l material through gravity
(3) Stellar wind breaks out but is confined to flow out along poles
(4) Eventually wind sweeps away cloud material

Question 5

Evolutionary Tracks for Contracting Prostars

Answer 5

(1) More mass → Shorter time to go through each stage

(2) Lower it is in main sequence, harder it is to form a star

Question 6

Disk Around Protostars

Answer 6

Disk of gas and dust seems essential to star formation

Question 7

Exoplanet

Answer 7

Planet outside our solar system

Question 8

Geneva Observatory (Didier Queloz & Michel Mayor)

Answer 8

First to discover a planet around a regular star

Question 9

Hot Jupiter

Answer 9

Giant planets really close to stores

Question 10

Planet Transit

Answer 10

Method for detecting exoplanets as they cross in front of the star causing the star to dim slightly

Question 11

Kepler

Answer 11

Launched to detect exoplanets