Milky Way Warped and Twisted


Accurate three dimensional map of Milky Way. Galaxy shows that it's warped and twisted. A report in the journal nature astronomy claims this woop spiral patent is being caused by talk of spinning of the milky way's massive in disk of stars than you observations of based on the positions of one thousand three hundred thirty nine syfy variable stars, which will use to map the milky ways real shape. They found the milky way's disk of stars becomes increasingly warped and twisted. The further away the stars are from the galactic Santa one of the study's authors. Professor Richard de grace from MacQuarie university says people usually think of spiral galaxies as being flat discs. The problem is trying to determine the rue shave avow. Galaxy is bit like standing in the middle of the woods trying to determine the exact size and shape of the hull forest. It's also the touristy difficult to determine distances from the sun to some parts of the milky ways. Gaseous disk without having a clear idea of what the disc actually looks like however of the past fifty years or so the have been some tantalizing hints that hydrogen clouds in the Milky Way could be warped from a great distance. I'll spiral galaxy look like thin disk of stars that obits roughly once every two hundred and fifty million years around the central region where hundreds of billions of stars provide all the gravitational glue native the whole the galaxy together. The Pat from dot matter that is, but it now seems this pull of gravity is far waker in the galaxies fi outta disk there. The hydrogen atoms making up most of the galaxy's gas disk no longer confined to a thin plane. Instead, they give the disk and s like a wolf to peerages coast by the huge man of toll coming from the spinning the milky way's massive in a disc of starves the Katie developing. This new three-dimensional map was recently published catalogue of young variable stars, none is classical Cepheids located in the wool Milky Way. Disc. Data on the east is was provided by Nashes wise wide field. Infrared survey explorer spacecraft the authors rebel, use a thousand three hundred thirty nine of these had variables to help them develop. They Matt and this allowed them that attempt that twisted appearance of the galaxies fire out a ragions classical Cepheids some four to twenty times as massive as the sun and up to one hundred thousand times as bright syfy at variables pulse. I that. He's expanding contract at set rates based on their intrinsic luminosity. And so that can be used the standard candles to measure cosmic distances because strana is no hang trinity luminous syfy variable star is because it's Paul sation. Right. They can determine how far away it must be. It's exactly the same. As looking at a row of straight lights down the road. You know, the vocal at the same brightness for the ones further down the road will appear dim it than the ones near it to you. This allows very accurate distances to determined for the stars with an era. Of only three to five percent. Then you research provides a crucial updated map for studies of the Milky Way, still emotions the origins of the milky way's disc. The grace reminds us that most of the matter in the milky ways dot matter, which is an intrinsic part of a universe. But the grace also points out that not only decide to not have any idea. What dot matter is not even sure exactly where it is. The new research the roszak of the Milky Way could help scientists better determine how dot matter is distributed around the Milky Way galaxy built those role surprised to find that they three dimensional collection of one thousand three hundred thirty nine syfy variable stars and the milky gas disk shared the stars tended to follow each other closely. The grace is that a scullery off his new insights into the formation of the Milky Way. He says perhaps more importantly, you found that in the milky way's outer regions the s like still a disk is warped in a progressively more. Twisted spiral Patton. Astronomers have observed dozens of other galaxies which have shown similar, Pat. Tens degrade says that means the milky way's twists rare. But not unique what we found is that towards the outer regions of anarchy by galaxy galaxy starts to DVI Toma flat bag shack without that was known for longtime in its distribution of gasoline by gossiping hydrogen atoms of which we knew for the last five decades or so in the region. The hydrogen gas would deviate from the plain become higher on bumps on one end and lower on the other end. Now, our study under the results have found fun for the first time that the young stars in the QA Trist by so-called seat variable stars, which are quite massive there for quite young followed that same kind of warped distribution where there is a clear deviation from does flatbed geic shed. But that's not everything also found is that the main direction of this war is not a straight line. But it starts to Marlins chase a spiral structure Espy go further for that. In the sense that this war becomes twisted at greater and greater radio as this. Anything to do at all with the total on stars within the galaxy coast by the galaxy's rotation. Yeah. So our interpretation of this result is not the massive disc of star king up. Most of the milk is rotating around the center of the galaxy. Every tune is sixty two three hundred million years, and it's dragging behind it the outer layers, which are less strongly gravitationally bound to the milky right because I've much further is and so that rotation the warped. Our two disc is slightly lagging behind is there any connection between this this warped structure in the thick and thin disks of the Milky Way is the correlation. And that's a good question. But we haven't actually looked up. Now having said that the dole cough the stars in. By are distributed into thin disc. That's ready to device majority of stars the thick disk is puffed up somewhat and it tends to extend to greater radio. But at much lower numbers of stars than the thinness. The the works distribution of stars would deviate from this thing this in the into the realm of the thickness. So there might be some dynamically. Action. But I would say about the warp itself is originates from the thin. That's probably must less associated with Findus. I don't think this has to do with the spiral structure of the milky QA such because it's quite well known by now death, the the longevity of the spiral arms is due to something called density Reich Swiss stars move around the center of the Milky Way, and they get attracted by the higher density of potato in despite alarm today that move faster towards spiral. I've spent more time there because of gravity and they move out slowly between his firearms that don't spend much time. That's that's the density by feary. I think there's a difficult. That's that's a completely different dynamical process in in this particular case, we believe that we really sees graft national torquing dragging behind of material by the inner massive disc. What do you need to do next for your research? Well, there's a couple of things that we can do first of all we looked at about thirteen hundred or so of the variables that's sizable sample. But it's know. You can always be improved one of the problems with our sample is that all of these stars were located on the near side of the nookie right centers on our side of the center. It would be great if he could get similar quality data on the other side of the QA center. So that we could see whether or not the features out. We have found are symmetrical, and that is more than just an academic exercise. The idea here is if the warts distribution of the seats in the twisting, this symmetrical either side of the Milky Way center, then we truly have a process here that works across the galaxy. Comex have suggested that what we we've seen might have been caused by the info of dwarf galaxy towards the region stuff, I'm Yukio. And if that's stick as you would only expect your side. So that's one thing that we would like to explore another thing, of course, is probably not very well. The European Space Agency is currently operating its guy satellite, which is meant to determine positions and distances to about a billion stars nuclei galaxy the first data released has has come out in the second releases Jew soon, but the full date. Percents will not be released for another three to five years by that time accurate three d map of nuclear galaxy. At hopefully, result will serve as a benchmark to hold those guy results against and I finally the other quite exciting prospects here is that by concentrating distribution of stars in our Milky Way. More a better more carefully before we may have a fighting chance of determining all the doc metro is located and that's still a big open question. That's professor Richard grace from Corean versity in Sydney,

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