An object 681 million light-years away may seem like a glorious & exquisite mess, but there’s a lot more going on that first glance indicates.
The object show-cased in a new hubbled image – called IC 2431 – is not a galaxy, but 3, which gather in a massive galactic merger that will 1 day ends like a large galaxy, with the scars of its cataclysmic encounter.
Such objects can help us understand how huge galaxies grow & evolve over millions & billions of years and how our Universe will continue to change in eons to come.
Galactic mergers may seem that they should be rare, given how much space is there, but they seem to be a great integral part of the galactic evolution process.
The Milky Way, for example, has undergone multiple galactic mergers during its 13.6 billion year history. Astronomers believe that galaxies are gravitationally drawn together, perhaps channeled along strands of invisible cosmic web that stretches across & plays a vital role in shaping the Universe, in-to clusters that slowly merge.
These collisions cause gravitational disturbances that shock & compress star-forming gas in galaxies, trigger waves of star formation as dense clumps in material collapse under their own gravity to-form baby stars.
A galaxy whose star formation rates are flagging likely to see a flurry of star burst activity during & following an interaction with another galaxy.
Binary galactic collisions are the most commonly seen galactic mergers, but there are also a number of triple mergers. These are not always easy-to-spot, depending on how complete merge is.
At later stages of a merger, the supermassive black holes at the centers of each galaxy become mutually drawn together & trapped in a binary or trinary orbit. As we have seen, sometimes one or more of these black holes can be obscured by dust. .
Astronomers believe that eventually these black holes will also merge, forming a huge supermassive black hole. We have not detected gravitational wave signals one-of-these colossal mergers, but this could be because they occur at a frequency that beyond the range of our current detectors.
The more these smashups identify, better we will be able to understand how they take place & model how they roll-out more than millions of years.
You can download the original image from the ESA Hubble website.