Meet Z 229-15, a celestial object that, depending on your mood, can be one of three different things – all at once. Image Z 229-15, released as the European Space Agency’s Image of the Week for the week of March 27, demonstrates what makes this strange space object so intriguing and why it has struck a chord with many astronomers since it was first discovered.
Located about 390 million light-years from Earth in the constellation Lyra, Z 229-15 is one of the few celestial objects that can be classified as multiple. The ESA says the object could be a quasar, or it can sometimes be identified as an active galactic nucleus (AGN). In other cases, it is defined as a Seyfert galaxy. Furthermore, the ESA says that this strange space object is all of these things at the same time due to a coincidence in the definition of these terms.
And it really is a galaxy. Looking at the image, you can easily see the spiral appearance of spiral galaxies. In addition, it contains AGN, when the region at the center of the galaxy is much brighter due to the supermassive black hole active in the core. A black hole is not itself brighter. On the contrary, all the material trapped in this strange space object is responsible for the luminosity.
But what makes this celestial object a Seyfert galaxy? This is where the quasar involved in Z 229-15 comes into play. You see, most quasars are so bright that they drown out the light from the stars in their galaxies. Sometimes quasars even emit jets of material. In this case, however, the stars are clearly visible, making the quasar in this bizarre cosmic object much dimmer than usual, creating what astronomers call a Seyfert galaxy.
It is intriguing to find a space object that is so many things definitively. Plus, it’s even more amazing to be able to look at an image taken by Hubble and see it all with your own eyes thanks to the powerful instruments on board the old telescope.