Star Evolution

Order them youngest to oldest

A

FE

D

B C

Order them youngest to oldest

F

E

H

DB C

G

A

Answer: D, F, H, C, A, G, E, & B

F

E

H

DB C

G

A

Life cycle of a star

• Stars age as they run out of hydrogen fuel.

• Large stars go through 5 main stages.

Stage 1

• All stars are “born” or begin in a large cloud of gas and dust called a nebula.

Stage 2

• A star will spend most of its life at this stage, main sequence. Hydrogen (H) undergoes nuclear fusion in the core.

Stage 3• When the H starts to run out, the star will

expand and cool down forming a red giant.

Red Super Giant Star in Orion Constellation

Stage 4

• Eventually, expanding will stop and the red supergiant will collapse violently, causing a bright supernova to appear.

Stage 5 (large star)

• As the core collapses, the gravity in the center is so strong, nothing can escape.

• Even light is trapped, producing a black hole.

Stage 5 (small star)

• Small stars (like our sun) will collapse into a small, Earth sized star giving off dim light as a white dwarf.

http://www.youtube.com/watch?v=iauIP8swfBY&feature=related

Order them youngest to oldest

A

FE

D

B C

Answer: A, F, D, C, then E or B

A

FE

D

B C

Which stages are missing? Why?

Star Evolution