Concept explainers
a
To Evaluate: The following prediction. “Type O stars have shorter lives than type G stars”.
b
To Evaluate: The following prediction.
“Type K supergiant stars produce iron before they explode as supernovae.”
c
To Evaluate: The following prediction:
Type F stars become much more luminous near the ends of their lives than they were as main-sequence stars.
d
To Evaluate: The following prediction:
“Type O stars do not become more luminous near the ends of their lives but do become redder.”
e
To Evaluate: The following prediction:
“Type M stars should have longer lives than type K stars.”
f
To Evaluate: The following prediction:
“Stars similar to Sun reach a maximum size of about 100 solar radii during the red giant stage.”
g
To Evaluate: The following prediction:
“Type K main sequence stars will become red giants when their cores run out of hydrogen.”
h
To Evaluate: The following prediction:
“Some stars become white dwarfs at the ends of their lives.”
i
To Evaluate: The following prediction:
“White dwarfs cool with time but do not change much in radius.”
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The Cosmic Perspective (9th Edition)
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