Suppose that we suddenly discovered that all these years we'd been wrong about the distance from Earth to the Sun,and it is actually 10% greater than we'd thought.How would that affect our estimate of the distance to the Andromeda Galaxy?
A)It would not have any effect on our estimate of the distance to the Andromeda Galaxy.
B)It would mean the distance to the Andromeda Galaxy is also 10% greater than we thought.
C)It would mean the distance to the Andromeda Galaxy is 10% less than we thought.
D)It would mean that all the objects we've assumed are standard candles really are not good standard candles,and therefore that we have no idea of the true distance to the Andromeda Galaxy.

Question

Quizplus · Accepted Answer

Our estimate of the distance to the Andromeda Galaxy is based on the measurement of its angular size and the assumption that the distance to the Sun is what we previously thought. If the distance to the Sun is actually 10% greater, then the distance to the Andromeda Galaxy would also have to be 10% greater to account for its observed angular size. Therefore, our estimate of the distance to the Andromeda Galaxy would need to be revised upward by 10%.

Suppose That We Suddenly Discovered That All These Years We'd