Million degree gas and "clumps" of matter

[Sun88]

Where would be the appropriate place to discuss this?

Is it ATM if we discuss Curcuit's, Electrical current and Plasma all at the same time? or is it now mainstream enough to discuss without hostility?

[Sun88]

I guess it would be ok to discuss here then?

[Swift]

Where would be the appropriate place to discuss this?

Is it ATM if we discuss Curcuit's, Electrical current and Plasma all at the same time? or is it now mainstream enough to discuss without hostility?

I don't see what you think this item has to do with "Curcuit's, Electrical current and Plasma". But that almost certainly sounds like ATM and so will only be discussed in ATM. If you would like to discuss the specifics of IGR J18410-0535, you may do that in this thread.

In the future, if you have a question like this, it might be best to PM a moderator, or use the Report function (black triangle with a ! in the lower left corner of every post), moderators don't check every thread for questions to us.

And hostility is never tolerated in any discussion, from any side.

[Sun88]

It's the wording mainly that's confusing, should I bring this up with Tammy Plotner or Frasier?

e.g

The x-ray data revealed four hours of gases being superheated to millions of degrees while being pulled into the gravitational field.

How's that stay a gas and not a plasma?

and

The ingestion of the clump material produced a dramatic increase in the X-rays released by the neutron star, which was detected with XMM-Newton

Ingestion? Clump of material? Increase in X-rays? Electric fields are good at that!! No mention of though?/

[Strange]

How's that stay a gas and not a plasma?

It is a fairly non-technical description so why mention something that isn't particularly relevant (unless you want to jump on the word "plasma" as proof of some crank theory).

[Nereid]

It's the wording mainly that's confusing, should I bring this up with Tammy Plotner or Frasier?

e.g

How's that stay a gas and not a plasma?

and



Ingestion? Clump of material? Increase in X-rays? Electric fields are good at that!! No mention of though?/

What you're reading is a UT story, based on an ESA Space Science News item.

As such, it will contain simplifications and, inevitably, distortions. It (the original) may even have been written by someone not all familiar with the relevant astronomy and/or astrophysics.

The online preprint will give you a better idea of what the observation is (was), and what the models used to analyse the observations are (XMM-Newton observations of IGRJ18410-0535: The ingestion of a clump by a supergiant fast X-ray transient). To get more than a superficial understanding of the strengths and weaknesses of those models, you can check out the references in that preprint.

If you any specific questions, why not ask them in the Q&A section?

[Sun88]

Read the abstract, at least they mentioned those majik magnetic fields!!

But stellar wind would be anologus to our solar wind, when "Clumps" of matter(from the abstract!!) come from our Sun we call them CME's and when these clumps of matter hit even Earths puny magnetic field we have Aurora's and they produce UV! Why not scale it up in power to you get X-Ray's?


Why does our sun do this and this sun uses gravity and accretion?

[Sun88]

I mean I was just watching a NASA video on a CME impacting Earth and noticed the similarities between our magnetic field arrangment and the one in the video, so was wondering what the difference would be?

[tusenfem]

Read the abstract, at least they mentioned those majik magnetic fields!!

What is so "majik" (the use of the word majic puts you squarely into the EU proponent circle) about magentic fields? The Sun has a magnetic field, the Earth has a magnetic field, nothing "majik" nothing special.

But stellar wind would be anologus to our solar wind, when "Clumps" of matter(from the abstract!!) come from our Sun we call them CME's and when these clumps of matter hit even Earths puny magnetic field we have Aurora's and they produce UV! Why not scale it up in power to you get X-Ray's?

And why would they not talk about "clump of matter"? Plasma is a gas is matter, it can "clump up" especially when a "blob" of plasma as a CME is emitted by the Sun or a star. That per definition has a higher density of plasma/gas/matter and thus can be considered to be a "clump".

We cannot scale up the aurora process to X-Rays, because it is impossible to generate X-rays through the process that is generating the aurora (which is energetic electrons interacting with the neutral gas of the atmosphere, exciting the atoms, which then fall back to their non-excited state emitting green (oxygen) or red (nitrogen) light (or sometimes even blue).

Why does our sun do this and this sun uses gravity and accretion?

Because the object that that stellar wind is interacting with is a COMPACT OBJECT, which is MUCH MUCH MUCH HEAVIER than the Earth

[Nereid]

Read the abstract, at least they mentioned those majik magnetic fields!!

But stellar wind would be anologus to our solar wind, when "Clumps" of matter(from the abstract!!) come from our Sun we call them CME's and when these clumps of matter hit even Earths puny magnetic field we have Aurora's and they produce UV! Why not scale it up in power to you get X-Ray's?


Why does our sun do this and this sun uses gravity and accretion?

tusenfem was kind enough to answer these questions of yours, in this thread.

I think they may be of greater interest, to a broader audience; why not post them - and others you may have - in the Q&A section?

[Sun88]

Thanks Neried,

Started a thread in Q&A

[Sun88]

The x-ray data revealed four hours of gases being superheated to millions of degrees while being pulled into the gravitational field.

Why do the authors dumb down there stories?

I mean they all know that a gas superheated to millions of
degrees is a plasma, not gas, don't they?

And considering they are talking about a "stellar wind", would it not be more appropriate to consider the dynamic electrical interaction of a conducting plasma moving thru a magnetic field??

Like our Sun blowing a CME off and it interacting with a planets magnetic field? When one hits our magnetic field all sorts of funny stuff happens.

No this object might just be very small and gravitationally significant but if there are magnetic fields, plasma and a release of energy then gravity will take a back seat to plasma physics.

Or are we still thinking there is electriciy in space , it just does nothing?

Like Stange said

How's that stay a gas and not a plasma?
It is a fairly non-technical description so why mention something that isn't particularly relevant (unless you want to jump on the word "plasma" as proof of some crank theory).

Not to promote a crank theory but to give the readers here the correct information and not dumbed down simplified science. Could you imagine if indeed they had not heard of plasma they may google it and find out what this majik "gas" is!!

@ Strange, why do you or the authors not feel calling a gas super heated to millons of degrees a plasma??

[Sun88]

ForGot to add the link it's in UT under Nuetron star burps stellar gas

[pzkpfw]

Sun88, do you actually have a question suitable for the Q&A forum, or are you really just wanting to rail against the presentation of science?

[Sun88]

Sun88, do you actually have a question suitable for the Q&A forum, or are you really just wanting to rail against the presentation of science?

O, I'll narrow the scope a little, is matter that has been heated to millions of degrees a gas or a plasma?

[HenrikOlsen]

O, I'll narrow the scope a little, is matter that has been heated to millions of degrees a gas or a plasma?

That's gas that likely turns to plasma as it's getting dragged in and heated through compression by gravity.
Doesn't make the description wrong, as it starts out as gas, turning to plasma on the way is just part of the process and a needless complication in an explanation for laypeople.

[Sun88]

That's gas that likely turns to plasma as it's getting dragged in and heated through compression by gravity.
Doesn't make the description wrong, as it starts out as gas, turning to plasma on the way is just part of the process and a needless complication in an explanation for laypeople.

From the data, the team was able to extrapolate the size of this “stellar burp” – about 100 billion times the volume of the Moon. From these estimates, astronomers can better understand the table manners of blue supergiant stars and how they transmit their matter into space as stellar wind. This new finding “shows that this particular blue supergiant does it in a clumpy fashion” and by knowing the size and mass allows for reserves to be placed on the process.

The "gas"=stellar wind=solar wind=plasma (The solar wind is a stream of charged particles ejected from the upper atmosphere of the Sun. It mostly consists of electrons and protons with energies usually between 10 and 100 keV. The stream of particles varies in temperature and speed over time. These particles can escape the Sun's gravity because of their high kinetic energy and the high temperature of the corona.)

Q Is this true HenrikOlsen? or if not what type of gas are they talking about?

[HenrikOlsen]

I'm having trouble understanding what your point of this question is, please elaborate.

[Sun88]

Why dumb science down for kids, Henrikolsen?

It is more confuderling to call a plasma a gas than to call plasma...well plasma? so why call a plasma, gas, Henrik?

Maybe if the Authors of this paper had read up on plasma instead of gas I would not be so confused!

I mean they should look at the pretty pictures like these

LINK


and

http://www.esa.int/images/Clump_animation_410_L.gif

[korjik]

The "gas"=stellar wind=solar wind=plasma (The solar wind is a stream of charged particles ejected from the upper atmosphere of the Sun. It mostly consists of electrons and protons with energies usually between 10 and 100 keV. The stream of particles varies in temperature and speed over time. These particles can escape the Sun's gravity because of their high kinetic energy and the high temperature of the corona.)

Q Is this true HenrikOlsen? or if not what type of gas are they talking about?

Actually, gas=stellar wind=solar wind=plasma isnt automatically true when talking about other stars. We dont really know the conditions of the environment around other stars all that well. A blue supergiant with very clumpy mass ejection could mean a very different mechanism than the Sun uses to eject mass.

I'll give you that they should prolly call it plasma instead of a gas tho.

[Jeff Root]

Gas which is plasma is still gas. Just because a gas is ionized,
even completely ionized, doesn't make it not gas. When a gas
becomes plasma, it generally retains the properties which define
it as a gas.

-- Jeff, in Minneapolis

[tusenfem]

In orde to facilitate this discussion, I moved the original discussion from UTstories to this thread.

[tusenfem]

Jeff Root has it completely correct.
A plasma is a gas with some extra qualities.
It still adheres to the gas law, albeit that sometimes the adiabatic constant is slightly different, but that does not make it not a gas.
(naturally we can make it even more confusing by claiming that plasma is a fluid, see Alfven and his magnetoHYDROdynamics.)

Apart from that, most of the general population has got no idea what it means when a newspaper says there is a blob of plasma, they may think that the local blood bank has exploded or something. Therefore saying that there is a superhot cloud of gas coming towards the Earth is better to visualise for the general publick and there is actually nothing wrong with the claim.

(netx to that, there are some questions for you that you nicely left unanswered in the UT thread, now in post #9)

[Nereid]

The Universe Today story Sun88's questions refer to is Neutron Star Burps Up Stellar Gas, by Tammy Plotner on June 29, 2011:

During a routine twelve and a half hour observation of star system IGR J18410-0535, the XMM-Newton caught an event that would make Emily Post proud… a not-so-discreet burp from a neutron star.

Although it would be ten days before the event was discovered, the ESA XMM-Newton space observatory team observed a faint star flare to almost 10 000 times its normal brightness. By utilizing x-ray wavelengths, the astronomers surmised ...

[slang]

Wikipedia to the rescue: Emily Post (October 27, 1872 – September 25, 1960) was an American author famous for writing on etiquette.

[iantresman]

We cannot scale up the aurora process to X-Rays, because it is impossible to generate X-rays through the process that is generating the aurora (which is energetic electrons interacting with the neutral gas of the atmosphere, exciting the atoms, which then fall back to their non-excited state emitting green (oxygen) or red (nitrogen) light (or sometimes even blue).

I believe that x-rays have been detected in the aurora. See:

• W. L. Imhof et al, "The Polar Ionospheric X-ray Imaging Experiment (PIXIE)", Space Science Reviews, Volume 71, Numbers 1-4, 385-408

[iantresman]

Gas which is plasma is still gas. Just because a gas is ionized,
even completely ionized, doesn't make it not gas. When a gas
becomes plasma, it generally retains the properties which define
it as a gas.

I'm going to disagree on the grounds that, while there are similarities between the two phases, the difference are sufficient to warrant two different terms. Otherwise we could argue that gas are hot liquids because they are both fluids that share similar properties. Hannes Alfvén was known for highlighting the importance of treating astrophysical plasmas in a proper theoretical fashion. He wrote:

"The basic difference between the first and second approaches is to some extent illustrated by the terms ionized gas and plasma which, although in reality synonymous, convey different general notions. The first term gives an impression of a medium that is basically similar to a gas, especially the atmospheric gas we are most familiar with. In contrast to this, a plasma, particularly a fully ionized magnetized plasma, is a medium with basically different properties: Typically it is strongly inhomogeneous and consists of a network of filaments produced by line currents and surfaces of discontinuity. These are sometimes due to current sheaths and, sometimes, to electrostatic double layers." -- Alfvén, Hannes, "Model of the plasma universe", IEEE Transactions on Plasma Science (ISSN 0093-3813), vol. PS-14, Dec. 1986, p. 629-638

So we could argue that plasmas are gases, when we mean they are gaseous, or gas-like, which is not really the same thing.

[iantresman]

Apart from that, most of the general population has got no idea what it means when a newspaper says there is a blob of plasma,

But science writers should (a) know better (b) be able to provide an explanation. And astronomers have no excuse, even if "gas" is the common term.

[Nereid]

But science writers should (a) know better (b) be able to provide an explanation. And astronomers have no excuse, even if "gas" is the common term.

I'm not so sure of that; did not Alfvén himself occasionally refer to at least some plasmas as "gas"?

More seriously, authors write for a particular audience (well, they should); if the audience can reasonably be expected to understand what "gas" means, in any given context, is it even rational to berate them as shoulda-known-better?

And what's with "plasma"? Is it even remotely sensible to crusade against the use of the term "metal" (as used by astronomers) because it includes elements that are obviously not metals (e.g. oxygen)? Where do you stop? Should we all be minutely examining every paper for use of "it's" when it should be "its"? or "less" when it should be "few"?

In terms of science writing, wouldn't our limited resources (time, especially) be better devoted to a campaign of using redshift instead of light-years (light travel time distance), in material on cosmology (to take just one example)?

[iantresman]

And what's with "plasma"? Is it even remotely sensible to crusade against the use of the term "metal" (as used by astronomers) because it includes elements that are obviously not metals (e.g. oxygen)? Where do you stop?

Alfven did indeed use the term gas, after all, the term "plasma" was only coined in 1928, and it takes some time for new words to enter common usage. The first astrophysics paper I can find that uses "plasma" in the title, dates from 1951.

Personally I believe that scientists should strive toward accuracy. Astronomers and science writers certainly have no problems introducing new terms all the time, so I don't see the use of "plasma" as a big deal.

In terms of science writing, wouldn't our limited resources (time, especially) be better devoted to a campaign of using redshift instead of light-years (light travel time distance), in material on cosmology (to take just one example)?

Obviously it depends on the subject being written about, and the context. But of course the space available to writers is not always available for lengthy explanations.