Cosmic enigma: A Quasar, AGN and Seyfert galaxy | Check out this all-in-one Hubble image

This image, taken by the Hubble Space Telescope, shows Z 229-15, a celestial object located 390 million light-years away in the Lyra constellation. It is classified as an active galactic nucleus (AGN), a quasar, and a Seyfert galaxy. Despite having different definitions, Z 229-15 encompasses all three because of their similarities.

AGNs are extremely bright region at the heart of certain galaxies that is dominated by the light emitted by dust and gas. This extra luminosity is due to the presence of a supermassive black hole at the galaxy's core that is actively accreting matter from its surrounding environment. As the matter spirals towards the black hole, it heats up and releases a large amount of energy across the electromagnetic spectrum, making AGNs some of the brightest objects in the universe.

The most powerful AGNs are known as quasars, which give rise to extremely luminous galactic centres. It is worth noting that all quasars are AGNs, but not all AGNs are quasars. They are amongst the most luminous objects in the known Universe, typically emitting thousands of times more light than the entire Milky Way.

Further, Seyfert galaxies are defined as active galaxies that host very bright AGNs or quasars while the rest of the galaxy is still observable. Z 229-15 is a Seyfert galaxy with a quasar, and that, by definition, hosts an AGN.

📷This NASA/ESA @HUBBLE_space Telescope image shows Z 229-15, a celestial object that is often defined as several different things: sometimes as an active galactic nucleus, sometimes a quasar and sometimes a Seyfert galaxy. But which is it really? 👉 https://t.co/SHvqe7n8gj pic.twitter.com/LnhzWXj4M2

— ESA (@esa) March 27, 2023

In the above image, you can see a spiral galaxy with two almost-straight arms coming from the left and right of the core that meet a starry ring around the galaxy’s edge. The core is glowing and a faint halo of light also surrounds the galaxy.

In addition to Z 229-15, the image also features one bright star with many diffraction spikes, and a few small stars all around on a black background