How is the numerical classification index for an elliptical galaxy calculated using its observed major axis (a) and minor axis (b)?
Answer
$10 imes (1 - b/a)$
The Hubble classification number for an elliptical galaxy is mathematically determined by the formula $10 \times (1 - b/a)$, based on the ratio of the observed minor axis to the major axis of its light profile.
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