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Similarly, the results from the work led by Dr Duarte Cabral suggest that the structure of the Milky Way is not that well defined and that the spiral arms are not that clear. “”The survey revealed that only a small proportion, roughly 10%, of these clouds have dense gas with ongoing star formation,” said James Urquhart from the University of Kent, the lead author of the third publication. “The large-scale survey, called SEDIGISM (Structure, Excitation and Dynamics of the Inner Galactic Interstellar Medium), has revealed a wide range of structures within the Milky Way, from individual star-forming clumps to giant molecular clouds and complexes, that will allow astronomers to start pushing the boundaries of what we know about the structure of our galaxy.” Indeed, it now looks like it is, hard to tell from the inside but: The multiple-arm type is sometimes grouped into the flocculent category.” Approximately 30% of spirals are flocculent, 10% are grand design, and the rest are referred to as “multi-armed”.

Self-propagating star formation is the apparent explanation for the structure of flocculent spirals. Unlike the well-defined spiral architecture of a grand design spiral galaxy, flocculent (meaning “fluffy”) galaxies are patchy, with discontinuous spiral arms. “A flocculent spiral galaxy is a type of spiral galaxy. Speaking of growing stellar mass through secular processes and in-situ star formation, that implies Milky Way may be more of a flocculent than grand design spiral galaxy. The fact that it grew most of its stellar mass through secular processes and in-situ star formation implies that it may not be the most representative example for understanding the evolution and assembly of the galaxy population, but is a correspondingly more pleasant environment to live in.” Not only did it assemble unusually quickly for its mass, but it also experienced a striking paucity of major accretion events, with only a handful of minor mergers shaping the Galactic stellar halo. “Focusing on the assembly history of the Milky Way, our results add to a growing body of evidence that the Milky Way experienced an unusual path to adolescence. The Milky Way merger tree implies our galaxy may have matured exceptionally fast and calmly. The high energy events must happen quite close – if they are narrow jets as here they have to lie in line of sight and if they are broad like supernova they dilute with the square of the distance – and we haven’t seen anything in 4 billion years. This affects the entire galaxy as the material snowplows into surrounding gas and dust. The “quasar winds” are propelling hundreds of solar masses of material each year. Using the unique capabilities of Hubble, astronomers have discovered that blistering radiation pressure from the vicinity of the black hole pushes material away from the galaxy’s center at a fraction of the speed of light. A quasar emits exceptionally large amounts of energy generated by a supermassive black hole fueled by infalling matter. This illustration shows a distant galaxy with an active quasar at its center. They emanate from quasars and tear across interstellar space like tsunamis, wreaking havoc on the galaxies in which the quasars live. Using the unique capabilities of NASA’s Hubble Space Telescope, a team of astronomers has discovered the most energetic outflows ever witnessed in the universe. This is an illustration of a distant galaxy with an active quasar at its center.