X-ray spacecraft reveals odd 'Cloverleaf' radio circle in new light (image)

[Admin]

Thanks to XMM-Newton, astronomers may know the powerful event that gave rise to the Cloverleaf odd radio circle.

X-ray spacecraft reveals odd 'Cloverleaf' radio circle in new light (image) : Read more

 

[Unclear Engineer]

The thing that springs to my mind when I hear that ORCs are the "sometimes" result of merging galaxies is that maybe they come from the ones which have their central supermassive black holes merge.

We predict that occasionally happens, but do we have models for the emissions when it does?

I wonder what such an event would do to life on any planets within the galaxy were those emissions started.

 

[billslugg]

SMBH's that have lots of stuff to feed on are quasars.

 

[Unclear Engineer]

We see lots of quasars that are not in the middle of ORCs, so I doubt that rapid feeding SMBHs are the source of ORCs.

But two SMBHs merging into one SMBH is a different situation. We think that must have happened many times because we don't know of any other way to build up billions of solar masses into a single black hole.

Something that can send out shock waves still visible when they have grown larger than galaxy clusters must have been more powerful than any other event that I can think of.

 

[billslugg]

I don't know anything about ORC's, all I know is merging SMBH's can form quasars. That's what you asked.

 

[Unclear Engineer]

I don't know anything about ORC's, all I know is merging SMBH's can form quasars. That's what you asked.

??? This article is about ORCs.

I didn't mention quasars, I only said that MERGING supermassive black holes seem to be a likely candidate for the creation of ORCs.

You FIRST said that quasars are caused by SMBH s feeding on lots of stuff, which is a likely situation during the merging of GALAXIES. I agree with that.

But, the MERGING of 2 SMBHs is not the same thing as a SMBH feeding on lot of stuff. It probably would not last as long as we have observed quasars to last, for instance. And, it would likely create some monster gravitational waves.

On the other hand, when 2 galaxies merge and their SMBHs approach each other and orbit close to each other, I would not be surprised if that does cause the SMBHs to feed rapidly on the stuff surrounding them, so that may be the situation for quasars, rather than a single SMBH somehow feeding rapidly. Two SMBHs orbiting each other closely would make the usual orbits for other stuff around each very unstable, probably enahancing the feeding rates..

 

[billslugg]

Right, you asked what happened when SMBH's merge and I gave you the answer, provided there is infeeding material - quasar. If it happened in isolation, not so much.

 

[Unclear Engineer]

You still seem to be missing my point. The actual merger of 2 SMBHs is not likely to be a long-term event. A quasar is probably NOT the actual merging event, but maybe the prelude to one, where 2 SMBHs are in close orbits BEFORE merging. That would fit the observation that there are a lot more quasars than ORCs in our field of view.

But, on the other hand, I am not clear on how far away we are currently able to detect ORCs. Maybe their population density is closer to the density of quasars.

It would not surprise me if all galaxy mergers went through phases that include their central SMBHs creating a quasar, and then merging and emitting an ORC shock wave, and then a quiescent period where the material near the now-merged SMBH is depleted by the shock from the merger.

Which brings me back to my wondering what all that energy emission in the center of a galaxy would do to the environments of planets orbiting stars in their galaxies. Could life survive? If so, then maybe there is some life form that is extremely old out there somewhere. IF not, then that would say something about the prospects for life forms older than the last merger time for any particular galaxy.

 

[billslugg]

Yes, I agree, the event of the merging of SMBH's is not what a quasar is. A quasar is simply a very large SMBH, formed at one time by the merging of smaller ones, that sits in a spot where a lot of matter can inflow. It is the flowing of matter into a very large SMBH that causes all the excitement. I don't know anything about ORCs.