Multiple Choice
A scientist claims that all red main sequence stars are 1 billion years old. Which of the following, if true, would prove that this claim is false?
A) The discovery of a red main sequence star in a star cluster where all the other stars are red giants or red supergiants.
B) Stellar evolution theory predicts that the main sequence lifetime of red stars can be as long as 100 billion years.
C) The minimum lifespan of a red main sequence star is estimated to be 10 billion years.
D) The discovery of a red main sequence star in a star cluster where the main sequence turnoff is about that of the Sun.
Correct Answer:

Verified
Correct Answer:
Verified
Q1: On a Hertzsprung- Russell diagram, where would
Q31: The choices below each describe the appearance
Q41: The more distant a star,the smaller its
Q56: The following questions refer to the sketch
Q80: We can measure the radii of stars
Q89: The spectral sequence in order of decreasing
Q97: If a star has a mass of
Q99: The axes on a Hertzsprung-Russell (H-R) diagram
Q100: The choices below each describe the appearance
Q106: The star Vega has an absolute magnitude