To an astronomer,what is a "standard candle"?
A) A standard light source that can be placed in a telescope,to which the brightness of stars and other objects can be compared
B) Any type of object whose absolute magnitude is known
C) Any galaxy whose redshift has been measured accurately
D) An accurately defined brightness scale for stars and galaxies,such as the magnitude scale

Question

Quizplus · Accepted Answer

A standard candle is an astronomical object whose luminosity or absolute magnitude is known or can be determined. These objects serve as important distance indicators in astronomy, as their observed brightness can be used to determine their distance from Earth through methods such as the inverse square law of light. Examples of standard candles include certain types of variable stars, supernovae, and Cepheid variables.

To an Astronomer,what Is a "Standard Candle