What method was used to determine the diameters of Pluto and its large moon, Charon?
A)observation of the sequential disappearance of the planet and the moon behind Earth's Moon in an occultation
B)photography from a visiting spacecraft
C)radio interferometry, with arrays of telescopes producing extremely high resolution images
D)observation of the mutual eclipses of the planet and the moon

Question

Quizplus · Accepted Answer

The diameters of Pluto and Charon were determined by observing their mutual eclipses. When one body passes in front of the other, it blocks out part of the other's light, allowing astronomers to calculate their sizes based on the amount of light obscured and the duration of the eclipse.

What Method Was Used to Determine the Diameters of Pluto