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Milky Way Is Square(ish), According To New Map
KentuckyFC writes "The structure of the Milky Way is notoriously difficult to work out because we see our galaxy edge on. That means nearer clouds and stars are superimposed on more distant ones and telling them apart is hard. However, astronomers have unveiled a new map based on velocity measurements made on 870 clouds of carbon monosulphide. This has revealed a number of new features of the Milky Way including a previously unknown spiral arm, some 30,000 light years from the galactic core. But the most surprising finding is that some of our galaxy's spiral arms are straight rather than curved, giving the Milky Way a distinctly square look. That's not quite as outrageous as it sounds. Astronomers know of a number of other galaxies with straight arms, such as the pinwheel galaxy M101. So ours probably looks something like this."
Evidence of a few years ago, revealed that the Milky Way was a barred spiral, http://apod.nasa.gov/apod/ap050825.html, wonder how these two findings will mix.
First off, the photo in the article is of the M101 Pinwheel Galaxy, not the Milky Way. Misleading, especially when you have to read all the way down to find out that tidbit and when the title includes 'New Map' we want to see the new map.
Secondly, we've known for quite some time that the Milky Way isn't a classic spiral. This Article gives a pretty interesting breakdown plus actual pictures.
I call it 'The Aristocrats'
No, the article is not describing a barred spiral galaxy. A barred spiral is one where there is a strong bar of stars across the galactic core (and extending well beyond it), and then "normal" spiral arms extend outward (mostly) from the two ends of the bar. The Milkyway is indeed thought to be a barred spiral.
What the article is describing is a spiral galaxy where the spiral arms themselves are straight in parts. And yes these have been observed (as shown in TFA where the Pinwheel galaxy is pictured, notice the lack of a central bar), but no it was not as far as I know theorized that the Milkyway had such a structure until now. Thus, news.
The enemies of Democracy are
Galactic arms aren't ejected from the core. They're just waves of star formation. They appear bright because they have more young, bright stars than the areas between arms.