Scientists have unlocked one of the biggest mysteries of quasars – the brightest, most powerful objects in the Universe – by discovering that they are ignited by galaxies colliding.
- First discovered 60 years ago, quasars can shine as brightly as a trillion stars packed into a volume the size of our Solar System, but until now it has remained a mystery what could trigger such powerful activity
- By observing 48 galaxies that host quasars and comparing them to over 100 non-quasar galaxies, scientists discovered that the phenomenon is ignited by galaxies colliding
- When two galaxies collide, gravitational forces push huge amounts of gas toward supermassive black holes at the center of the remnant galaxy system that results from the collision – just before the gas is consumed by the black hole, it releases extraordinary amounts of energy in the form of radiation, resulting in a quasar
- The Milky Way is likely to experience its own quasar when it collides with the Andromeda galaxy in roughly five billion years’ time
First discovered 60 years ago, quasars can shine as brightly as a trillion stars packed into a volume the size of our Solar System. In the decades since they were first observed, it has remained a mystery what could trigger such powerful activity. New work led by scientists at the Universities of Sheffield and Hertfordshire has now revealed that it is a consequence of galaxies crashing together.
The collisions were discovered when researchers, using deep imaging observations from the Isaac Newton Telescope in La Palma, observed the presence of distorted structures in the outer regions of the galaxies that are home to quasars.
Most galaxies have supermassive black holes at their centers. They also contain substantial amounts of gas – but most of the time this gas is orbiting at large distances from the galaxy centers, out of reach of the black holes. Collisions between galaxies drive the gas towards the black hole at the galaxy center; just before the gas is consumed by the black hole, it releases extraordinary amounts of energy in the form of radiation, resulting in the characteristic quasar brilliance.
The ignition of a quasar can have dramatic consequences for entire galaxies – it can drive the rest of the gas out of the galaxy, which prevents it from forming new stars for billions of years into the future.
This is the first time that a sample of quasars of this size has been imaged with this level of sensitivity. By comparing observations of 48 quasars and their host galaxies with images of over 100 non-quasar galaxies, researchers concluded that galaxies hosting quasars are approximately three times as likely to be interacting or colliding with other galaxies.
The study has provided a significant step forward in our understanding of how these powerful objects are triggered and fueled.
Professor Clive Tadhunter, from the University of Sheffield’s Department of Physics and Astronomy, said: “Quasars are one of the most extreme phenomena in the Universe, and what we see is likely to represent the future of our own Milky Way galaxy when it collides with the Andromeda galaxy in about five billion years.
“It’s exciting to observe these events and finally understand why they occur – but thankfully Earth won’t be anywhere near one of these apocalyptic episodes for quite some time.”
Quasars are important to astrophysicists because, due to their brightness, they stand out at large distances and therefore act as beacons to the earliest epochs in the history of the Universe. Dr. Jonny Pierce, Post-Doctoral Research Fellow at the University of Hertfordshire, explains:
“It’s an area that scientists around the world are keen to learn more about – one of the main scientific motivations for NASA’s James Webb Space Telescope was to study the earliest galaxies in the Universe, and Webb is capable of detecting light from even the most distant quasars, emitted nearly 13 billion years ago. Quasars play a key role in our understanding of the history of the Universe, and possibly also the future of the Milky Way.”
Reference: “Galaxy interactions are the dominant trigger for local type 2 quasars” by J C S Pierce, C Tadhunter, C Ramos Almeida, P Bessiere, J V Heaton, S L Ellison, G Speranza, Y Gordon, C O’Dea, L Grimmett and L Makrygianni, 13 February 2023, Monthly Notices of the Royal Astronomical Society.
Such a long time for such a simple concept to hit the big time. One can get the feeling that the “big bang community” had to be led to this conclusion silently kicking and screaming.
It has nothing to do with standard cosmology as such, of which galaxy mergers is a common model. If anything it supports what is already known about standard cosmology.
Told you not to follow me around the first time you tried this garbage with me, you stalking failed collective gravity theory jackass.
So first you get a snot puppet but that not enough. Back in helpful passive-aggressive fanged culturally-braindead blackface effect, selling more scrambled cosmic egg stuff. Kind of a mixed-message royal schizoid shape-shifting effect you have going on, champ.
“silently kicking and screaming.”
Because, in space, no-one can hear you scream?
Quasars are “Little Big Bangs”. Black Holes suck and time runs backwards.
There are no models of black holes where “time runs backwards”. How could they be such, anyway!?
The thing about cosmic egg heads is their unfalsifiable religion always comes with huge egos and they never learn or teach anything useful.
Cosmology is a science, so it is based on learning and teaching. Everyone knows that.
And that is quite the opposite to your idea of never-useful superstition as how it is done.
“Cosmology is a science.”
Politics is a science too. Stop your idiotic stalking, all you have is worthless overdone pseudo-science factoids.
To the point, the article describes something not earlier known and demonstrates how that observation is forwarded to the society at large.
Ever so much more to the point, inappropriate use of predatory fanged imagery in support of cosmic egg cracking bent spacetime is highly suggestive of injectable abuse.
“Considering merger stage, we find that a majority of the disturbed objects in our sample are observed in a pre-coalescence phase (61 +8 -9 percent), in contrast with the idea that quasars are triggered at the peaks of gas-rich mergers and become visible post-coalescence as the circumnuclear dust is dispersed (Sanders et al. 1988).”
So that’s about 40 % of their quasars which both merges and triggers quickly, which is quite a reasonable statistical sample.
IIRC gas funneling to the center of galaxies (or at least Milky Way), it is thought features like bars and arms ease that. About 60 % of galaxies are spirals.
Some jackass on yahoo life is selling the notion that galaxies running around and crashing together to form quasars was obvious to cosmic egg salesmen decades ago, although only shameless royal revisionism is old hat for them.