Z 229-15, the luminous celestial object captured by the NASA/ESA Hubble Space Telescope, lies at a distance of 390 million light-years from Earth in the constellation Lyra. It has been identified as an active galactic nucleus (AGN), quasar, and Seyfert galaxy, prompting the question as to which definition truly applies. The answer is that Z 229-15 is all three of these classifications simultaneously due to their common characteristics. AGNs are energetic and highly luminous sources of radiation; quasars can have extreme luminosities and radio jets; and Seyfert galaxies have distinctive optical spectra and luminous cores. In this case, all three designations seem to overlap, making Z 229-15 an intriguing cosmic phenomenon to explore further.
An Active Galactic Nucleus (AGN) is a small, highly luminous region at the core of certain galaxies, such as quasars and Seyfert galaxies. AGNs are powered by supermassive black holes, which generate huge amounts of energy as material is drawn into the swirling disk surrounding them. This energy is released across the electromagnetic spectrum, making AGNs hundreds to thousands of times brighter than their host galaxies. AGNs are key components in the study of galaxy formation and evolution, as they reveal the powerful and complex processes happening at galactic centres.
Quasars are an incredibly bright and distant type of AGN, with some being hundreds of millions of light-years away. Z 229-15 is relatively close to Earth in comparison, therefore making it a local quasar. Other AGN’s can be so bright that the rest of the galaxy can’t be seen, but Seyfert galaxies usually have a very luminous AGN (quasar), while the rest of the galaxy is still visible. Z 229-15 is a Seyfert galaxy that contains a quasar and an AGN. Classifying astronomical objects can be difficult, but with a bit of research and analysis, it can help us further understand the universe.