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Astronomers find the edge of the Milky Way

Is this a non-sequiter or just poorly phrased?

  > 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.
9 hours agodotancohen

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.

2 hours agoeventualcomp

I actually am not following what the ambiguity is - stars farther out from the center are younger, no?

7 hours agohappytoexplain

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.

7 hours agokadoban

The father out from the center of the galaxy they look, the younger the stars are.

an hour agorafram

The location of the Earth is completely irrelevant. "closer" and "farther" refer to the center of the galaxy.

36 minutes agojibal

When does "starting in the center" mean anything besides "starting in the center"?

The earth is not the center of the galaxy

7 hours agomalfist

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.

an hour agofuryofantares

He didn't say that. He said earth is nearer to the center of a spiral arm.

6 hours agoassimpleaspossi

What does the center of a spiral arm have to do with the center of the galaxy?

2 hours agomalfist

the location of earth has precisely zero to do with the topic

2 hours agodylan604

Poorly phrased. The most recent stars are on the edges. The inner stars were first, hence the “working outwards”.

9 hours ago_factor

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.

6 hours agoww520

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.

39 minutes agojibal

From Earth (where astronomers are) looking "out"ward (away from the bulge).

an hour agofuryofantares
[deleted]
6 hours ago

Try: "the farther out [from the center] astronomers look"

7 hours agoJumpCrisscross

It is beyond obvious what they mean.

9 hours agocolechristensen

[dead]

8 hours agolayer8

Just the daily post that makes me feel small and insignificant.

9 hours agoneals

I prefer that feeling much more than the modern sense from social media where everyone is abnormally important

9 hours agodylan604

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.

2 hours agorambojohnson

Great. Next Laniakea

8 hours agoyrcyrc

Incredible. "Hi honey, what did you do at work today? Casually discovered the edge of the galaxy. How are you?"