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Plasmoid Jets Energize Intercluster Medium

The attached story's headline is silly but the story's content is interesting. The story includes the observed M87 jets.

In the following, [AGN] is used in place of black holes for readability.


The scientists used sophisticated simulations to show how powerful jets from [AGN] are disrupted by the motion of hot gas and galaxies, preventing gas from cooling, which could otherwise form stars.
These [galaxy] systems are embedded in very hot gas known as the intracluster medium (ICM), all of which live in an unseen halo of so-called ‘dark matter’.

A large number of galaxies have [AGN] in their centres, and these often have high speed jets of material stretching over thousands of light years that can inflate very hot lobes in the ICM.

As galaxies move around in the cluster, the simulation shows they create a kind of ‘weather’, moving, deforming and destroying the hot lobes of gas found at the end of the [AGN] jets. The jet lobes are enormously powerful and if disrupted, deliver vast amounts of energy to the ICM.

my comment:

All of these references to jets and hot lobes of gas are as observed near the plasmoid in M87.

wikipedia excerpt ===

In pictures taken by the Hubble Space Telescope in 1999, the motion of M87's jet was measured at four to six times the speed of light. This phenomenon, called superluminal motion, is an illusion caused by the relativistic velocity of the jet. The time interval between any two light pulses emitted by the jet is, as registered by the observer, less than the actual interval due to the relativistic speed of the jet moving in the direction of the observer. This results in perceived faster-than-light speeds. Detection of such motion is used to support the theory that quasars, BL Lacertae objects and radio galaxies may all be the same phenomenon, known as active galaxies, viewed from different perspectives. It is proposed that M87 is a BL Lacertae object (with a low-luminosity nucleus compared with the brightness of its host galaxy) seen from a relatively large angle. Flux variations, characteristic of the BL Lacertae objects, have been observed in M87.

Observations indicate that the rate at which material is ejected from the [AGN] is variable. These variations produce pressure waves in the hot gas surrounding M87. The Chandra X-ray Observatory has detected loops and rings in the gas. Their distribution suggests that minor eruptions occur every few million years. One of the rings, caused by a major eruption, is a shock wave 85,000 light-years in diameter around the [AGN]. Other features observed include narrow X-ray-emitting filaments up to 100,000 light-years long, and a large cavity in the hot gas caused by a major eruption 70 million years ago. The regular eruptions prevent a huge reservoir of gas from cooling and forming stars.

my comment:
The wikipedia description of the M87 jets is very close to this ' stormy weather' in the news story.
Despite that strong similarity M87 is never mentioned in the story!

I noticed the link of M87, quasars, and BL Lac objects. I missed that link before my October 20 post on quasars.

The plasmoid jets inject plasma into the ICM. The ICM is expected to cool but it does not. The temperature measurement method is not mentioned.

Chandra sometimes images the ICM as an active cloud so the ICM generates synchrotron radiation down to that X-ray wavelength.

Part of the story is their attempt to model the jets. If they do not start with the observations of the M87 plasmoid mechanism then they will start wrong.


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