This new image of a source called IC 4271, taken by NASA’s Hubble Space Observatory, is an interesting pair of spiral galaxies about 800 million light-years away. The smaller one covers a part of the larger one, which belongs to a class of active galaxies called Seyfert galaxies.
Seyfert galaxies are named after the astronomer Carl K. Seyfert, who published a scientific paper on spiral galaxies with very bright emission lines in 1943. Today we know that such galaxies account for about 10% of the total number of galaxies in the universe. They belong to the class of “active galaxies” – i.e. galaxies with supermassive black holes in the center that accredit the material. This process is accompanied by the release of large amounts of radiation. The active nuclei of Seyfert galaxies have maximum brightness when observed in visible light. The larger galaxy in the image is a Seyfert type II galaxy, meaning it has a source with very high brightness in the infrared and visible ranges.
Data collected during Hubble observations designed to study the role of dust in shaping the energy distributions of low mass disk galaxies were used to create the image. These Hubble-based observations included six pairs of galaxies in which one component covered part of another galaxy. The wide wavelength range of Hubble’s Wide Field Camera 3, as well as its high resolution, allowed the researchers to map the foreground galaxy’s dust disk in fine detail across ultra-violet, visible, and infrared light.
Because the galaxy IC 4271 is a Seyfert type II galaxy, the image is dominated by objects obtained from observations in the optical and infrared ranges. The colors in the image correspond mainly to the colors of the optical range, but purple corresponds to ultraviolet radiation, and red corresponds to the near-infrared range.
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