What parameter determines the numerical designation (0 to 7) in the E0 to E7 classification system?

Answer

Apparent flattening

The scale devised by Edwin Hubble classifies these galaxies based purely on their apparent flattening as viewed from Earth, ranging from nearly round (E0) to most elongated (E7).

What parameter determines the numerical designation (0 to 7) in the E0 to E7 classification system?

#Videos

A Simple Guide to Classifying Elliptical Galaxies - YouTube

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