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A Spiral Structure in the Inner Oort Cloud
- girvo 1y agoMeta: 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...
- recursive 1y agoI got the same thing. The correct answer for me was the fancy desserts, because they go on a fancy restaurant table I guess.
- SCUSKU 1y agoHere's the PDF: https://iopscience.iop.org/article/10.3847/1538-4357/adbf9b/pdf https://iopscience.iop.org/article/10.3847/1538-4357/adbf9b/...
- tonyhart7 1y agoI fucking hate that chaptcha
- samyok 1y agoyou 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/pdf https://iopscience.iop.org/article/10.3847/1538-4357/adbf9b/...
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- graemep 1y ago> 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... But someone's metrics are showing 20+ bot request blocked!
- gs17 1y agoIt's a really poor design. "Fits the theme", not "is this object". I had a lighthouse and it wanted me to click sharks, because they're both "water" themed. I asked Gemini to solve this "puzzle" and it could do it. Whatever weird filter they're trying to apply to the images doesn't work well enough.
- coke12 1y agoOur own solar system has what appear to be spiral arms. Very cool finding.
- dotancohen 1y agoYes, 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 If I'm not mistaken, and this might be outdated, the galactic spiral structure is attributed to massive clumping - massive particles attract.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 1y agoIt'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 1y agoWell, 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!
- ninkendo 1y agoAlso, galaxy spirals are very much an open question. Galaxies don’t rotate the way you’d expect from the matter you see, and it’s the main reason we hypothesize the existence of dark matter. Unless dark matter is the reason the Oort Cloud develops spiral arms, I’d wager the mechanisms are quite different.
- doctoboggan 1y 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/1TuacHdAeZ5J8wNAJvlYv435x9Oj6Bhhb/view?usp=sharing https://drive.google.com/file/d/1TuacHdAeZ5J8wNAJvlYv435x9Oj...
- tristramb 1y agoYou might also appreciate W. W. Morgan's account of his discovery of the Perseus Spiral Arm of our Galaxy in his observational data on OB stars: "This was in the fall of 1951, and I was walking between the observatory and home, which is only 100 yards away. I was looking up in the sky ... just looking up in the region of the Double Cluster [in Perseus], and I realized I had been getting distance moduli corrected the best way I could with the colors that were available, for numbers of stars in the general region ... Anyway, I was walking. I was looking up at the sky, and it suddenly occurred to me that the double cluster in Perseus, and then a number of stars in Cassiopeia, these are not the bright stars but the distant stars, and even Cepheus, that along there I was getting distance moduli, of between 11 and 12, corrected distance moduli. Well, 11.5 is two kiloparsecs ... and so, I couldn’t wait to get over here and really plot them up. It looked like they were at the same distance ... It looked like a concentration ... And so, as soon as I began plotting this out, the first thing that showed up was that there was a concentration, a long narrow concentration of young stars ... There are HII regions along there too ... And that was the thing that broke [the problem] down." Full article here: https://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?2008JAHH...11....3S&defaultprint=YES&filetype=.pdf https://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_que...
- YesThatTom2 1y agoThe ads for Hayden Planetarium show mostly highlight that it’s narrated by Pedro Pascal. But, yeah, the spiral thing is cool too.
- AStonesThrow 1y agoThe past few planetarium shows in my neck-of-the-woods have featured narration by the likes of David Tennant and Diego Luna. As I understand it, these shows are sort of syndicated and shared among many locations. Some of them were several years old.
- curtisszmania 1y ago[dead]
- dedicate 1y agoI 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!
- HappMacDonald 1y agoKamina most likely approves
- eli_gottlieb 1y agoI understood that reference.
- Eduard 1y agocould someone explain the significance of this finding? Is it remarkable for being a definable structure in a previously thought random distribution of bodies that make up the Oort cloud?
- machenesonk 1y agocould universe have a spin?
- twic 1y agoThey could really do with a 3D model of this, it's rather hard to visualise from the views from two different directions.