A Spiral Structure in the Inner Oort Cloud

71 gnabgib 13 6/4/2025, 11:22:07 PM iopscience.iop.org ↗

Comments (13)

doctoboggan · 2h ago
> The spiral structure was first identified by examining the simulation in the Hayden Planetarium in preparation for a new space show that describes and visualizes the Oort cloud.

That's a pretty cool way to discover something like this. Here is the simulation animation:

https://drive.google.com/file/d/1TuacHdAeZ5J8wNAJvlYv435x9Oj...

dedicate · 58m ago
I always pictured it as, like, a super scattered snowball fight way out in the boonies. How does something so delicate even hold that shape out there?

This completely change how we should think about the 'edge' of our solar system!

coke12 · 4h ago
Our own solar system has what appear to be spiral arms. Very cool finding.
dotancohen · 2h ago
Yes, this is interesting, finding complex structures that are found at multiple scales is rather amazing.

The paper attributes the solar system's spiral structure to the galactic tide. If I'm not mistaken, and this might be outdated, the galactic spiral structure is attributed to massive clumping - massive particles attract.

("Massive" meaning particles with mass - not necessarily large. "Particles" meaning macroscopic particles, not subatomic.)

dachris · 1h ago
It's amazing, yes, and at the same time, it makes perfect sense.

(Somewhat) similar mechanisms are at work whether you're pulling together stars into a galaxy, hydrogen gas into a solar system or water towards the drain of your bath tub - a pull towards the center, the centripetal force, slight variations producing "artifacts".

dotancohen · 26m ago
Well, I would not call these two mechanisms similar, though the artifacts may be similar. I wonder if in fact the spirals are similar, for that matter if mathematicians even have terminology for different types of spirals.

The spirals shown in the paper do look like idealised spirals of very young galaxies, shortly after the bar phase. I wonder, other than spirals, what other artifacts such processes might cause.

Imagine an accretian disk undergoing fusion in spiral-shaped filaments!

girvo · 5h ago
Meta: I can't even get into the site, the hCaptcha shows an image (a table and chairs) that never shows up even after 20+ "Skip" clicks...
samyok · 4h ago
you have to click on the fruit cups, as it asks what fits the "theme" of the image.

here's the pdf, though: https://iopscience.iop.org/article/10.3847/1538-4357/adbf9b/...

SCUSKU · 5h ago
dcassett · 1h ago
I've been using the links browser for HN and fall back to a full-fledged browser if I get blocked. Links (and Lynx) give me no problems with TFA.
w10-1 · 4h ago
Also no access, even after passing human validation - screen dark.
recursive · 5h ago
I got the same thing. The correct answer for me was the fancy desserts, because they go on a fancy restaurant table I guess.
tonyhart7 · 5h ago
I fucking hate that chaptcha