The Hubble Space Telescope is an expert at imaging distant galaxies, bringing mysterious galactic features into the light. In the case of one particular elliptical galaxy, around 150 million light-years distant, Hubble has revealed a conundrum and a possible mechanism behind why some galaxies look so old.
NGC 4696 possesses huge clouds of dust and gas, spiraling through the galaxy’s structure to its core, but this material isn’t being used for star formation. In fact, NGC 4696 is populated with ancient stars and researchers hope to use this stunning example to help us understand why there are so many massive galaxies like it.
NGC 4696 occupies the huge Centaurus galaxy cluster which consists of hundreds of galaxies bound together by gravity. Though the cluster is vast, NGC 4696 stands out from the crowd as it is so bright. It’s so bright, in fact, that it has the moniker “Brightest Cluster Galaxy.” It is known to have an active core occupied by a supermassive black hole that appears to be consuming these beautiful spiraling tendrils.
These dusty structures have a width of around 200 light-years and they all knit together, creating a conveyor belt of material flooding into the black hole. The black hole then heats the material that spirals in, blasting superheated gases away from the core that sculpt the infalling dust into the shape as seen so clearly by Hubble.
It’s well known that central supermassive black holes, which are known to live in the cores of the vast majority of galaxies, have a significant role in regulating the amount of star formation.
In the case of NGC 4696, it appears the galaxy’s core is physically shaping the structure of these dusty tendrils and an international team of astronomers, headed by researchers at the University of Cambridge, suspect that powerful magnetic fields are threading through the galaxy’s structure, corralling the dust in such a way that its funneled into the black hole. But the black hole is the engine behind it all, erupting with hug amounts of energy and actively stifling star formation.