According to the provided framework, what is the key differentiator when comparing the age demographics across different galaxy types?
Answer
The proportion of young stars relative to the total stellar population
While the absolute age of stars varies, the most critical metric for distinguishing types is the ratio. Spiral and irregular galaxies maintain a high proportion of new stars because they retain their fuel supply, whereas ellipticals have an overwhelmingly ancient population.
Related Questions
Galaxies are primarily categorized based on which key characteristic?What mechanism concentrates star formation within the spiral arms of spiral galaxies?Why do the spiral arms of spiral galaxies generally appear bluer than the central bulge?What essential fuel source is generally lacking in elliptical galaxies, preventing active star birth?What is the common descriptive term for elliptical galaxies due to their stellar population characteristics?What structural feature defines irregular galaxies in contrast to spirals and ellipticals?According to the provided framework, what is the key differentiator when comparing the age demographics across different galaxy types?What finding complicates the simple narrative that massive elliptical galaxies are entirely old?What factor causes the most massive galaxies across all types to generally stop forming stars relatively early in cosmic history?Why can dwarf irregular galaxies often sustain star formation for longer periods than giant spirals?