![]() ![]() The active galaxy family includes the exotically named quasars and blazars. The energy output of these nuclei can sometimes outshine their host galaxies. NGC 1672 is a member of the family of Seyfert galaxies, named after the astronomer, Carl Keenan Seyfert, who studied a family of galaxies with active nuclei extensively in the 1940s. A few bright foreground stars inside our own Milky Way Galaxy appear in the image as bright, diamond-like objects. They also appear reddened as they shine through NGC 1672’s dust. ![]() Galaxies lying behind NGC 1672 give the illusion they are embedded in the foreground galaxy, even though they are really much farther away. NGC 1672’s symmetric look is emphasized by the four principal arms, edged by eye-catching dust lanes that extend out from the center. ![]() Delicate curtains of dust partially obscure and redden the light of the stars behind them. In the new image from the NASA/ESA Hubble Space Telescope, clusters of hot, young, blue stars form along the spiral arms, and ionize surrounding clouds of hydrogen gas that glow red. It appears that the bars are short-lived, begging the question: will non-barred galaxies develop a bar in the future, or have they already hosted one that has disappeared? This allows the bar portion of the galaxy to serve as an area of new star generation. These observations, announced in February 2013, were made using the X-ray telescope satellite NuSTAR.Astronomers believe that barred spirals have a unique mechanism that channels gas from the disk inwards towards the nucleus. The central supermassive black hole in the active nucleus, which has a mass of about 2 million solar masses, rotates at close to the speed of light. Such galaxies are quite common - two thirds of spiral galaxies are barred according to recent estimates, and studying others can help astronomers understand our own galactic home. NGC 1365 and other galaxies of its type have come to more prominence in recent years with new observations indicating that the Milky Way could also be a barred spiral galaxy. Different parts of the galaxy take different times to make a full rotation around the core of the galaxy, with the outer parts of the bar completing one circuit in about 350 million years. NGC 1365, including its two outer spiral arms, spreads over around 200,000 light-years. Astronomers think NGC 1365's prominent bar plays a crucial role in the galaxy's evolution, drawing gas and dust into a star-forming maelstrom and ultimately feeding material into the central black hole. The spiral arms extend in a wide curve north and south from the ends of the east-west bar and form an almost ring like Z-shaped halo. The inner bar structure likely rotates as a whole more rapidly than the larger long bar, creating the diagonal shape seen in images. This second bar is more prominent in infrared images of the central region of the galaxy, and likely arises from a combination of dynamical instabilities of stellar orbits in the region, along with gravity, density waves, and the overall rotation of the disc. Within the larger long bar stretching across the center of the galaxy appears to be a smaller bar that comprises the core, with an apparent size of about 50″ × 40″. ![]() NGC 1365 is barred spiral galaxy in the Fornax cluster. NGC 1365, also known as the Great Barred Spiral Galaxy, is a double-barred spiral galaxy about 56 million light-years away in the constellation Fornax. ![]()
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