What physical measurement is quantified by the index D for elliptical galaxies?

Answer

Apparent degree of flattening

The index D quantifies the apparent shape, calculated using the galaxy's major axis (a) and minor axis (b) with the formula D = 10(1 - b/a).

What physical measurement is quantified by the index D for elliptical galaxies?

#Videos

Do Elliptical Galaxies Have A Disk Component? - Physics Frontier

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