this post was submitted on 17 Nov 2024
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Astronomy

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[–] HurlingDurling@lemmy.world 18 points 1 month ago (1 children)
[–] partiallycyber@ttrpg.network 42 points 1 month ago (2 children)

Disclaimer: I'm not well versed in astrophysics.

Ok, so: you know how Earth is part of the solar system? And the solar system is part of a large collection of stars and planets called a galaxy?

Well, there's lots of galaxies out there! And scientists for a long time have been trying to figure out how they formed - how did all the stars get close to each other? Why aren't they just randomly drifting around?

Currently, everyone believes that there's this magic stuff called "dark matter" that pulled the stars together to make galaxies. Kinda like how magnets pull things close to them!

And because galaxies are so big it would take a long time to pull the stars close together! Which means young galaxies would look less bright because the stars aren't all close together yet, like they are with older galaxies.

So that's what everyone believes.

But we're getting pictures from a really strong telescope that's showing us that young galaxies are brighter than we expected! Which is weird and exciting because it means that young galaxies might have been pulled together faster than we used to think! And our old theories about galaxy creation might be wrong!

There's a theory that explains how galaxies could come together quickly, without dark matter, but it doesn't really fit with many other theories we have about how the world works, so lots of people are thinking really hard to figure out how they might fit together.

And that's what science is all about! Finding out new information that shows you that you were wrong in the past, and using that information to figure out new ways to act and think in the future!

[–] quicksand@lemmy.world 11 points 1 month ago

Thanks for Bill Nye-ing this for me. Appreciate your summary

[–] HurlingDurling@lemmy.world 11 points 1 month ago

That's awesome! Thanks for the explanation!

[–] echo@lemmings.world 6 points 1 month ago

There is no gravity... Earth just sucks...

[–] RaymondPierreL3@aus.social 6 points 1 month ago (1 children)

@fossilesque
MOND refuses to go away and is still a valid hypothesis not to be dismissed.

[–] Deconceptualist@lemm.ee 12 points 1 month ago

Hypothesis, sure. But it needs to hold up to testing better than Lambda-CDM if we're gonna call it the best hypothesis.

[–] Idontevenknowanymore@mander.xyz 5 points 1 month ago (1 children)

I understood about 8% of that article but it's still fascinating.

[–] Deconceptualist@lemm.ee 17 points 1 month ago* (last edited 1 month ago) (1 children)

I follow this stuff (as a non-physicist) so I understood it. It's a pretty shallow article and mentions there there's still evidence for the widely-accepted Lambda-CDM model. But like most coverage of MOND it declines to give good alternate explanations for specific key observations like the Bullet Cluster, gravitational lensing, and galactic outer rotational speeds.

So yeah a new observation that fits better with MOND than LCDM is certainly interesting, but it doesn't flip the tables unless it does a better job explaining the prior phenomena too.

[–] Idontevenknowanymore@mander.xyz 4 points 1 month ago (1 children)

I understand the two theories and the difference between them, but when my brain tries to comprehend how gravity actually works I experience a comprehension failure.

[–] Deconceptualist@lemm.ee 4 points 1 month ago

Haha, well if it's any consolation, nobody fully understands it. That's why we're still looking at various theories of quantum gravity or even random gravity.

[–] Kolanaki@yiffit.net 5 points 1 month ago

Is is the theory that little, invisible gremlins are just constantly pulling things down? 🤔

[–] burgersc12@mander.xyz 3 points 1 month ago

Dr Becky has a few different videos on MOND and what the current (video is from last year) scientific view of it is. Very informative, she's awesome!