Here's why:
* Elliptical galaxies come in a wide variety of sizes, from dwarf ellipticals that are only a few thousand light-years across to giant ellipticals that can span hundreds of thousands of light-years.
* Spiral galaxies, while large, have a more consistent size range. They typically have diameters of 10,000 to 100,000 light-years.
* Irregular galaxies are often smaller and less massive than spiral or elliptical galaxies.
Therefore, due to their massive size range, elliptical galaxies exhibit the greatest diversity in diameter and mass among galaxy types.
