> Disk galaxies like the Milky Way form stars “inside-out” — starting from the center and working outwards through the disk. So, as a general rule, the farther out astronomers look, the younger the stars are.
Do they meant looking out from Earth (which is actually nearer to the center of a spiral arm than to either end) or out from the galactic bulge. Either way doesn't make sense.
To use an analogy, to add to everybody else: it's like rings on a tree stump. The innermost part of the stump is the oldest; the outer the youngest. Earth is on one of those in-between rings, neither the oldest nor the newest - doesn't matter which of the in-betweens, to be honest.
Suppose now that you're an ant on the middle ring of that tree stump. No matter which way you're looking from Earth's middle-ring, either the rings will get gradually older and then younger with increasing distance (if you're looking towards the center-ish), or the rings will get strictly younger (if you're looking away from the center-ish).
This analogy obviously breaks down if you delve into details but that should give a better intuition to what's going on.
Looking from Earth at the stars closer to the center of a galaxy, they are found to be older. Looking from Earth at the stars closer to the edge of a galaxy, they are found to be younger.
Earth isn't relevant. The stars at the center of the galaxy developed first, and development proceeded from the inside out, so the youngest stars are on the edge ... then they get older from there on out, as the stars beyond the edge broke away from the galaxy. The bottom of the age U is the location of the formative edge.
Seriously. Being meaningless and insignificant gives you more freedom, and nowhere to hide from what you do with it. I’ve never understood cosmic dread. It feels like a release valve instead of a threat.
Better, adblocker-friendly article (original press release): https://www.um.edu.mt/newspoint/learn/2026/theedgeofthemilky...
Paper: https://www.aanda.org/articles/aa/full_html/2026/04/aa58144-...
Is this a non-sequiter or just poorly phrased?
Do they meant looking out from Earth (which is actually nearer to the center of a spiral arm than to either end) or out from the galactic bulge. Either way doesn't make sense.
To use an analogy, to add to everybody else: it's like rings on a tree stump. The innermost part of the stump is the oldest; the outer the youngest. Earth is on one of those in-between rings, neither the oldest nor the newest - doesn't matter which of the in-betweens, to be honest.
Suppose now that you're an ant on the middle ring of that tree stump. No matter which way you're looking from Earth's middle-ring, either the rings will get gradually older and then younger with increasing distance (if you're looking towards the center-ish), or the rings will get strictly younger (if you're looking away from the center-ish).
This analogy obviously breaks down if you delve into details but that should give a better intuition to what's going on.
I actually am not following what the ambiguity is - stars farther out from the center are younger, no?
The Earth isn't the center of the galaxy, so this feels confusing/confused:
> So, as a general rule, the farther out astronomers look, the younger the stars are.
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When does "starting in the center" mean anything besides "starting in the center"?
The earth is not the center of the galaxy
The Earth is where the astronomers are. If they are looking outward (away from the center) then the further they look, the younger the stars.
He didn't say that. He said earth is nearer to the center of a spiral arm.
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Poorly phrased. The most recent stars are on the edges. The inner stars were first, hence the “working outwards”.
Looking from Earth at the stars closer to the center of a galaxy, they are found to be older. Looking from Earth at the stars closer to the edge of a galaxy, they are found to be younger.
Earth isn't relevant. The stars at the center of the galaxy developed first, and development proceeded from the inside out, so the youngest stars are on the edge ... then they get older from there on out, as the stars beyond the edge broke away from the galaxy. The bottom of the age U is the location of the formative edge.
From Earth (where astronomers are) looking "out"ward (away from the bulge).
Try: "the farther out [from the center] astronomers look"
It is beyond obvious what they mean.
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Just the daily post that makes me feel small and insignificant.
I prefer that feeling much more than the modern sense from social media where everyone is abnormally important
Seriously. Being meaningless and insignificant gives you more freedom, and nowhere to hide from what you do with it. I’ve never understood cosmic dread. It feels like a release valve instead of a threat.
Great. Next Laniakea
Incredible. "Hi honey, what did you do at work today? Casually discovered the edge of the galaxy. How are you?"