Which of the following objects is considered useful to astronomers as a "standard bulb" for determining distances?
A) type Ia supernovae
B) planets that resemble Earth
C) K-type stars
D) the brightness of the bulge in a galaxy's center
E) the size of the largest diameter open cluster in a galaxy

Question

Quizplus · Accepted Answer

Type Ia supernovae have a known intrinsic brightness, making them useful as "standard bulbs" for determining distances to far-off galaxies. By observing how bright the supernova appears from Earth, astronomers can calculate its distance by comparing its apparent brightness to its known intrinsic brightness.

Which of the Following Objects Is Considered Useful to Astronomers