The milky way. Another recent paper came out not so long ago, suggesting something unusual in one of the galactic arms of our galaxy. One of the arms in the milky way seems to have some kind of a break. A spiral arm break something that was very recently discovered using the new data from the gaia telescope, something that until now was not actually known and something that was not suspected. But its not unusual. And i wanted to explain why, while also explaining some of the other relevant details about this particular paper and about the study, but first of all its important to understand that its actually kind of difficult for us to see what our galaxy looks like. Mostly because were located inside of it pretty deep inside of it and one of the main difficulties in trying to understand what the galaxy looks like is actually establishing distances to various objects. For example, we might be able to see certain density of stars in the region somewhere, but we dont really know how far away those stars are from one another, but because of esas gaia telescope. In the last few years, more and more data came out and became available to try to figure out a lot of these different structures, mostly because it discovered extremely precise distances to billions of different objects out there, and because of this, we now have quite a lot Of data to start figuring out what the actual galaxy looks like and what some of the parts of the galaxy might represent.

This is why a lot of different discoveries in regards to the structure of the galaxy, including one of the recent ones that should be popping up somewhere there at some point, have essentially been made after guy emission became operational, and so this recent study used the data From the gaia telescope, combining it with the infrared data from the spitzer telescope, the telescope responsible for creating whats known as the glimpse survey, also known as the galactic legacy, infrared midplane survey extraordinaire. The survey and the telescope perfect for studying the galactic arms and theres. A really important reason for that, if you were to look at a typical galactic arm, a typical galactic arm would contain an over density of various star, forming gas clouds and a lot of different young stars producing a lot of infrared radiation. As a matter of fact, most of the infrared radiation would be coming from the galactic arms, and so by using infrared survey, it would be much easier to establish where the galactic arms are located and to study their structure and to study their shape and to date, The most accurate representation using the data from these telescopes makes the galaxy look something like this. This is from nasa and jpl lab with our sun located somewhere right here right between two major galactic arms, but inside a small galactic arm. But at the moment this is still a relatively rough representation in the last few years. Some major discoveries have already suggested that, for example, our galaxy could be wobbling and producing all sorts of wave like shapes, while also not really being flat, but instead being somewhat warped.

Weve also recently discovered at least one minor arm on the outskirts of the galaxy, and there are probably a lot of these arms pretty much all over the place. So, even though the galaxy seems to possess four major arms, there could be a lot of smaller ones that have still not been found, but in this paper the scientists decided to focus on one of the major arms thats, essentially closest to us, the sagittarius arm. So essentially, this arm that kind of goes right here and the one that astronomers often refer to as sagittarius karina arm, because its actually technically two arms it starts as sagittarius arm. Then it sort of disappears and becomes karina arm and today is believed to be one of the most pronounced arms in our galaxy, with a tremendous amount of young stars giant molecular clouds and a lot of beautiful and easily visible in infrared regions that allow us to Study this arm with a lot of detail and because generally young stars and a lot of nebular clouds, usually align with the location of these galactic arms by precisely measuring the distances to those nebula its thus possible to sort of start mapping the location of various arms. In a galaxy – and in this case, spitzer telescope, combined with gaia telescope, created a perfect combination to study all of this, and so when they put all of this data together, they did discover something unusual inside the arm itself.

So normally, when you look at a typical galactic arm, the so called angle of pitch is about 12 degrees. Mathematically speaking, it refers to the angle that can be visualized this way. So this angle, right here in the galactic arm in our galaxy, is believed to be approximately 12 degrees, but the analysis of several objects, such as nebular clouds present in the sagittarius arm, established another object with an angle of about 60 degrees. A collection of young stars collection of nebular clouds forming something thats about 3 000 light years in length, something that essentially crosses the arm itself. Making it stick out quite dramatically if you were to look at it from the top. With this being the first major structure inside the galactic arm that has such a dramatic different orientation compared to everything else around it and, interestingly enough, a lot of super famous nebula seem to be part of the structure. For example, the very famous eagle nebula thats, actually famous for this right here that contains the famous pillars of creation, is apparently inside the structure, with the other famous objects being the omega nebula, the trifid nebula. And lastly, the lagoon nebula that you see right here with all four nebula being part of this unusual formation, but i guess the question is: is this something completely unexplainable or is this something that was actually expected and the answer seems to be the latter? This seems to be what the scientists often refer to as the feathers or the spurs of a galactic arm, and many such spurs have been discovered in other galaxies.

The majority of spiral galaxies that have galactic arms usually have them straight, like you see right here, but approximately thirty percent of all galaxies discovered tend to have somewhat unequal and somewhat feathery looking spirals. These are known as the flocculant spirals, and so approximately thirty percent of all galaxies out there that have spiral. Arms have flocculant spiral, arms. They have these unusual feather like formations. The word flocculant in this case just means fluffy. So essentially, they have spiral, arms that are somewhat discontinuous and somewhat broken up in places with the galaxy known as ngc 2841 being the most commonly used example, and because so many of them seem to have these unusual formations for many many decades now the scientists were Kind of wondering well, is our galaxy part of the majority that has relatively straight arms, or is our galaxy also somewhat flocculant? Does it have these fluffy feather like formations and looks like according to the study right here? The answer is that it does seem to have these focal informations. The arms are not entirely straight, they seem to have brakes and they seem to have these feathers with the first feather discovered. So far being this unusual formation that currently is referred to as the far 3 kiloparsec arm and so in reality, our galaxy might actually resemble something like this more so than something like this, at least to some extent. It does seem to contain these feathers and they do seem to break some of the arms or okay.

The reality is that theres at least one of these feathers, but chances are that there are a lot more of them out there and overall, it seems to be a pretty interesting structure. It contains approximately 25 different star, forming regions or star forming nebula, but also seems to be spinning with the rest of the galaxy at exactly the same speed as everything around it. So its definitely part of the galaxy and its definitely not something unusual created by some unusual collision, and if your next question is, but how was it created? The answer to that is that well at the moment, nobody really understands how these structures are made. Okay, so there are at least some models such as this one right here: the model known as the stochastic self propagating star formation, that kind of tries to explain the formation of these structures. But the more realistic answer in this case is that its still being debated and its still not entirely well understood, and so to answer how this is created, i guess, were gon na have to wait a few years until someone figures this out and until someone proves This definitively and by the way theres at least one more paper im going to post in the description that goes on a very detailed investigation and analysis of a lot of different feathers located in a lot of different galaxies. With some of these galaxies containing dozens and even hundreds of these fatal affirmations, so definitely something that exists in the lord of other galaxies out there anyway.

On that note, thats all i wanted to mention check out all of the relevant links in the description below. Thank you for watching subscribe. If you still havent and share this with someone who has learned about space and sciences, maybe come back tomorrow to learn something else.

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