If a star were moved 10X farther away, its absolute magnitude would drop five magnitudes.
True
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False
TRUE
The statement is true.
To understand why this is true, we need to understand the concepts of absolute magnitude and the inverse square law of brightness.
Absolute magnitude is a measure of the intrinsic brightness of a celestial object, specifically how bright it would appear if it were placed at a standard distance of 10 parsecs (32.6 light-years) from Earth. It helps us compare the brightness of different celestial objects.
The inverse square law of brightness states that the brightness of an object decreases as the square of the distance from the observer increases. In other words, if you double the distance to an object, its brightness decreases by a factor of four. Similarly, if you move an object 10 times farther away, its brightness decreases by a factor of 10 squared, which is 100.
Now, let's apply this to the statement. If a star were moved 10 times farther away, its distance from Earth would increase, resulting in a decrease in its apparent brightness. According to the inverse square law, the decrease in brightness would be 100 times (10 squared).
Magnitude is measured logarithmically, which means that each magnitude represents a specific factor in brightness. A difference of five magnitudes corresponds to a brightness ratio of 100 times (2.512 raised to the power of 5). Therefore, if a star is moved 10 times farther away, its apparent brightness decreases 100 times, which is equivalent to a drop of five magnitudes.
Hence, the statement is true.