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"Massive galaxies that stopped forming stars (known as massive quiescent galaxies) are plausible progenitors of giant elliptical galaxies." Could someone expla
by Geenkaas 3y ago
"Massive galaxies that stopped forming stars (known as massive quiescent galaxies) are plausible progenitors of giant elliptical galaxies."
Could someone explain a bit more what this means? Is it that those galaxies were "born" out of the quiet galaxies, or shaped into ellipses because of them?
- layer8 3y agoNot an expert, but here is my understanding: Elliptical galaxies are typically quiescent (and spiral galaxies aren’t). The “massive” quiescent galaxies observed in the early universe are however smaller than the “giant” elliptical galaxies observed in the more recent universe. It is assumed that the latter evolved from the former, most likely by merging with other galaxies. This question of how exactly they evolve(d) is the subject of continued research. More generally, see also https://en.wikipedia.org/wiki/Galaxy_formation_and_evolution https://en.wikipedia.org/wiki/Galaxy_formation_and_evolution.
- denton-scratch 3y agoA "progenitor" is an ancestor; it means that the quiescent galaxy "plausibly" turns into an elliptical galaxy.
- zuminator 3y agoIn this case precursor might be more precise than ancestor.
- denton-scratch 3y agoAgreed; I knew there was something wrong with "ancestor" when I typed it. [Edit] A progenitor is literally an ancestor; I answered GP's question. It's "progenitor" that should instead be "precursor", in the featured article.