type 1 Seyfert galaxy

Type 1 Seyfert galaxies are a class of galaxies characterized by their active nuclei. These galaxies were first identified by astronomer Carl K. Seyfert in 1944. A key feature of Type 1 Seyfert galaxies is the presence of broad emission lines in their nuclear spectra, which indicate a central concentration of hot gas expanding at very high speeds, up to thousands of kilometers per second. While appearing normal in typical images, these galaxies are exceptionally strong emitters of infrared radiation, and many also produce significant amounts of radio energy and X-rays. Seyfert nuclei are thought to be powered by supermassive black holes at their centers, similar to quasars, but with a lower energy output. It is estimated that about 1 percent of spiral galaxies exhibit Seyfert properties.123