Shocked gas in galaxy collisions

Shocked gas in galaxy collisions
An image of the colliding galaxies known as The Antennae, taken in the optical and near-infrared. Astronomers using the ALMA submillimeter array have found evidence for shocked gas near the nucleus of the northern (upper) galaxy, and argue that it is due to material infalling onto the nuclear region. Credit: ESA/Hubble & NASA

Collisions between galaxies, especially ones rich in molecular gas, can trigger bursts of star formation that heat the dust and result in their shining brightly in the infrared. Astronomers think that there is also significant gas inflowing to the central regions of galaxies that can stimulate starburst activity. Inflowing gas, as it collides with the gas in the inner regions, should produce powerful shocks that should make the gas itself glow. Some evidence for gas inflows on galactic scales has been discovered, but there have been few observational confirmations of the effects of the inflowing material in the inner region of the galactic nucleus.

CfA astronomers Junko Ueda, David Wilner, and Giovanni Fazio used the ALMA submillimeter array to study the gas in the central regions of the Antennae galaxies, the nearest mid-stage merging system (about seventy-two million light-years away). The of the system is estimated to be about ten solar-masses per year, much of it in the off-nuclear region (the so-called "overlap ") of the two galaxies; the two nuclear regions themselves appear to have lower star formation rates.

The astronomers examined the star formation in one of the two nuclear regions, whose gas abundance is as much as one hundred times more than in the Milky Way's center. They measured the emission from five organic molecules, CN, HCN, HCO+, CH3OH (methanol), and HNCO (isocyanic acid), looking for evidence of shock activity. And they found it. The methanol and isocyanic acid in particular were detected, for the first time in this object, and show clear evidence ion their intensities, ratios, and velocities for being excited by shocks. The evidence from the geometry of the emission suggests that the shocks are produced by infall, rather than from the collision. However, there is also the possibility that the induced burst of produced local shocks that contributed to the activity.

Although further work is needed, the results so far indicate that infalling material is likely responsible.


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More information: Junko Ueda et al. ALMA observations of the dense and shocked gas in the nuclear region of NGC 4038 (Antennae galaxies), Publications of the Astronomical Society of Japan (2017). DOI: 10.1093/pasj/psw110
Citation: Shocked gas in galaxy collisions (2017, May 1) retrieved 20 July 2019 from https://phys.org/news/2017-05-gas-galaxy-collisions.html
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RNP
May 01, 2017
An open access copy of the paper can be found here; https://arxiv.org...0002.pdf

May 01, 2017
One of these days the plasma ignoramuses will get a clue, until then enjoy the pseudoscientific mumbo jumbo DNP linked.

May 01, 2017
One of these days the plasma ignoramuses will get a clue, until then enjoy the pseudoscientific mumbo jumbo DNP linked.

explain what is actually happening using evidence then, so all of us ignoramuses can get learned.

May 01, 2017
The only misnomer left is that gravity is thought as the driving force. The prime mover is not gravity, it is charge separation. Alllllll the other evidence is there only it's being filtered through the obsession over gravity. And yet nobody knows why mass even exhibits gravity.

The mainstream paradigm is unintentional pseudoscience. Their equations are beautiful and work with each other fantastically, only they don't describe reality. Rather, the views of reality are distorted to meet the strict (and wrong) confines of general relativity. This yields dark matter that 'must' be there or dark energy that 'must' be there while everything we can physically observe in the universe only makes up a mere 4% of what 'must' be there... all only if gravity is the prime mover.

May 01, 2017
None of the hypothetical dark nonsense is needed with charge separation as the fundamental driving force. A proton and electron both have same charge and thus same electrical potential. However, the proton has a much larger mass, so the electron will move faster under same force. Poof... you have charge separation, which leads to double layers, which leads to cellular structures and regions of differing properties, etc. Gravity (which is probably of electromagnetic nature as is) has its role of course, but it's an afterthought in the grand scheme of forces we observe, left for us to play around in areas of comparatively futile activity.

May 02, 2017
Decades of laboratory research has shown that the theoretical musings of mechanical shocks and gravity driven plasma activity are but the fanciful imaginings of people who seem unaware of real plasma physics phenomena such as double layers, CIV, and electric discharges.

May 02, 2017
Decades of laboratory research has shown that the theoretical musings of mechanical shocks and gravity driven plasma activity are but the fanciful imaginings of people who seem unaware of real plasma physics phenomena such as double layers, CIV, and electric discharges.

Then please, use your vast laboratory experience to explain the source of the specific emission spectrum they were looking at.
Also, why wouldn't plasma be affected by gravity? Plasma is made of particles and ions, hence has mass, therefore should have an interaction with gravity. Explain why it wouldn't.

May 02, 2017
It's not that plasma isn't affected by gravity, it is. The fact that EM forces acting on plasmas is 39 orders of magnitude stronger than gravity is why gravity is nearly meaningless in these discussions.

May 02, 2017
It's not that plasma isn't affected by gravity, it is. The fact that EM forces acting on plasmas is 39 orders of magnitude stronger than gravity is why gravity is nearly meaningless in these discussions.

OK, so describe the emissions that are being observed with your 39 orders of magnitude stronger EM force. Should be pretty simple since there has been so much lab based experiments run on plasma.
Is plasma causing these galaxies to collide? pretty fancy plasma you got there!
thanks!

May 05, 2017
It's not that plasma isn't affected by gravity, it is. The fact that EM forces acting on plasmas is 39 orders of magnitude stronger than gravity is why gravity is nearly meaningless in these discussions.

There's no charge screening with gravity. I'm sure cd has no clue what that means, but it torpedoes his argument.

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