Slashdot Mirror
Milky Way Is Surrounded By Halo of Hot Gas
New submitter kelk1 writes "If the size and mass of this gas halo is confirmed, it also could be an explanation for what is known as the 'missing baryon' problem for the galaxy [...] a census of the baryons present in stars and gas in our galaxy and nearby galaxies shows at least half the baryons are unaccounted for [...] Although there are uncertainties, the work by Gupta and colleagues provides the best evidence yet that the galaxy's missing baryons have been hiding in a halo of million-kelvin gas that envelopes the galaxy."
Iiiii'm the CAT!
Seriously, we're not going to get out of this galaxy alive.
A feeling of having made the same mistake before: Deja Foobar
Excuse me.
that envelopes the galaxy
Surely you meant to use the verb, i.e. "envelops".
"... a few hundred times hotter than the surface of the sun." That's very warm.
Kharma is like a boomerang. Mine is broken.
Lets hope it's just hot gas instead of an energy dampening field like in Poul Anderson's Brain Wave story.
retain it's 1,000,000K for 14,000,000 years?
"I don't know, therefore Aliens" Wafflebox1
http://en.memory-alpha.org/wiki/Galactic_barrier
more cowbell
...I think you guys just like saying the word "baryon".
/* No Comment */
Dammit we we're supposed to meet The Covenant for about another 530 years!
Hold on a second... so they just discovered the Galaxy is surrounded by gas that's the same temperature as the surface of the sun, and is 300,000 lightyears across... possibly extending far into other galaxies... I'm going to take a wild stab here and say that, if that's true it probably pervades the entire universe... Isn't this the biggest scientific discovery in the past decade? What effect does this have on Dark Matter, Dark Energy, etc... etc...
Sorry, that was me. BIG burrito last night.
Did anybody notice that nobody has yet to comment on the obvious failure of this science journalist to correctly identify hot gas as a plasma? It's actually not clear to me why Slashdot runs so many of these science articles. The crowd here is so argumentative and hostile when it comes to defending conventional ideas in science, but there's no culture of accuracy with respect to plasmas to back up the incredible assault we've seen here over the years on the Electric Universe / plasma cosmology types. There always seems to be far more interest in finding the joke in the press release than there is in talking about the ramifications of these findings to the various conflicting views of the universe. Surely, this is not the final incarnation of scientific dialogue ...
Where No Man Has Gone Before
As a plasma physicist, I'm not bothered or concerned about them calling it gas. When interacting with the general public to discuss plasma related research, sometimes you find yourself having to make a choice between trying to teach a person what a plasma is, or teaching them what you are doing with it. Attention spans, and time/space are sometimes limited with such interactions and you have to choose your priorities.
Of course every time a story comes up about missing matter being found, people want to know the impact on the need for dark matter. There is evidence that suggest how much matter in the universe is made out of baryonic matter (protons and neutrons... essentially anything made of atoms), and how much is made out of non-baryonic matter. The latter category is dark matter. In addition to the missing non-baryonic matter, there is also a bunch of missing baryonic matter, which what is being found by studies like this. That wasn't counted as part of dark matter in the first place. It is not like every bit of new baryonic matter we find cuts into the dark matter slice of the pie, they are still trying to fill up the normal matter slice,
This just accounting for regular own (baryonic) matter. The Halo is still mostly "Dark" matter, which is non-interacting. (It may be WIMPs, i.e., non-baryonic, or it may be quark nuggets, i.e., baryonic, but either way it is non-interacting.)
If the galaxy is surrounded by a halo of incredibly hot gas, wouldn't this put a damper on any kind of intergalactic travel?
...has Rush Limbaugh really gotten that big?
Aren't we all supposed to have learned about solid, liquid, gas and plasma back in grade school? I seem to recall having the concept explained over and over again from before high school and right through it. I can see the people who pass through school without learning to read having trouble with it, but it's a depressing thought that the ones who managed to become journalists missed the entire concept.
The previous story is the Romney-Ryan Space Policy.
There is a barrier surrounding the galaxy!
Same AC you replied to...
Although many people do learn that in school, they either don't remember it or never learned anything about what a plasma actually is other than it is some mysterious hot stuff, and can't see how it is pretty similar to gas in a lot of situations.
If anything, I've run into more trouble with people who paid attention to such things in school and not much else. They get stuck with this notion that everything has to be pigeon-holed into one of those categories (which makes it even worse if they were taught only three states). There seems to be a bit of lack of sense of how the different states relate to each other, and that the boundary between them can be fuzzy in many cases. This is especially so with plasma, since in some cases the electrical properties don't matter much and it acts just like a gas. Other times you can have partially ionized plasmas where the electrical effects are there, but not dominant (or even see such effects in things like semiconductors or conducting liquids, which sometimes get referred to as plasmas when speaking analogously, but are also different).
For stories like this though, the difference probably doesn't matter much. I think they could have easily called it plasma, and the number of people it would have confused would have been minimal, although I don't know if it would have added anything.
My first glance at the thread title, I thought it said: Milky Way is Surrounded by a Halo of Hot Grits :D
Me thinks this is another unfortunate 'Oh Shit ... I Ate The Fucking Data' again.
Oh well ... nice try by the ... 'authors' of this phantasmagoria.
Everyone knows a Milky Way is surrounded by a halo of milk chocolate.
no...chocolate
Signed /Troll
Let's see. At the average thermal velocity of
What's the escape velocity of a particle in this halo?
Somewhere close to the airspeed velocity of an unladen swallow (European)
Donte Alistair Anderson Roberts - hi son!
Karma: Chameleon
of the Great A'Tuin
Go on, I dare you.
Surrounded by a halo of hot gas... The Milky Way Galaxy and Washington D.C.
GAS!
Me? I'm a plasma psychologist. I watch TV and help the people on it.
They have bleaching for that.
Anyone who has worked around plasma knows it is a bipolar bitch with anger, vengeance and pass-aggression issues. We've tried hiring a psychologist to deal with it, but the antidepressants keep clogging up our vacuum system. We might try lithium instead, as I heard good results on the Lithium Tokamak Experiment at getting plasma to "calm the fuck down."
Looks like the universe is lactose intolerant...
Aren't we all supposed to have learned about solid, liquid, gas and plasma back in grade school?
Considering how many comments ON A NERD SITE say "loose" instead of "lose", aliterate things like "there cars are over their" and "The tomato's are in season", I think the fact that they don't know what a plasma is is pretty understandable.
Free Martian Whores!
Unfortunately, this presents a serious impediment to our ability to understand the universe. Plasmas and gases react completely differently to electromagnetic fields and gravity. Einstein's Relativity was postulated at a time when it was not known that plasma was the universe's preferred state for matter. Once we sent probes into space, it became undeniable that charged particles are zipping around outside of the ionosphere. The situation above and below the ionosphere is completely different with regards to plasma's prevalence. Without a clear distinction between plasmas and gases, the public has no way of understanding that vital point. They will simply assume that space is filled with gases, solids and liquids -- no different from what we see immediately around us. This will lead them to assume that gravity is the universe's dominant force, even though we know that it is also the weakest.
The electric force is 10^39 (or somewhere around there) stronger than the gravitational force, and the error bars on attempts to measure the gravitational "constant" have been *increasing* over time -- not decreasing. If one is to be a side-effect of the other, it's somewhat apparent that gravity would be a side-effect of electricity.
To place the blame entirely upon the public is to miss the larger picture of what is happening with the dissemination of information about plasmas. The scientific community has completely failed the public in teaching them the concepts of laboratory plasmas. It's not the public's fault, because the information has *never* been presented in a format which is understandable. There's no excuses for what is happening, because 99.999% of what we see with our telescopes is matter in the plasma state. How in the world are people supposed to have a clue about what's happening in the universe when scientists are not properly explaining the behavior of the universe's dominant state of matter? Some common sense on this issue is long, long overdue.
I didn't say you needed to skip explaining what a plasma is every time, only that it is a choice that comes up frequently, and you chose to go either way as appropriate.
To say the information has "*never*" been presented is pretty far from how I've seen it. Every physics department I've worked in has had seminars and talks open to the public, and open houses with public demonstrations, and participated in annual learn/community fairs run by the universities. Because I've worked at places with decent number of plasma researches, they always had a long list of researchers eager to show off plasma science. Especially at the fairs with demonstrations, the plasma related demonstrations are additionally quite popular, to the point some people trying to teach more fundamental, intro physics topics grumble over losing people. I've assisted with such demonstrations at annual conferences before too. Colleagues much more well spoken than me have given numerous interviews describing the nature of plasma physics in far more detail than this PR piece (which is really on par with a PR piece in any other field), and write articles for pop-science publications.
But plasma physics is a rather complex topic. I've spent enough time describing to people how sound waves work in air, while plasma has a dozen different kinds of waves depending on the situation, not even getting into some of the dusty plasma stuff. Similar to, but not as bad as quantum mechanics, there are a lot of effects easier to explain and think about using math. Some of the parameters and factors vary many orders of magnitude from what is experienced by people in day-to-day life. This is not to say it is impossible, but there is definitely a challenge here. Once the "ooh, shiny and glowy" wears off, keeping the attention of the public to explain thing in more detail can get tricky. It also makes it harder to make sure teachers have some understanding of such subjects if they are going to teach it. Heck, I have enough friends working in other physics fields if asked about switching to plasma physics with, "No, screw all of that E&M crap, I don't want to be waist deep in Bessel functions, way too tedious." But I'm not trying to cry that plasma physics has it harder than other fields, it is about on par with any other physics topic that goes beyond what people are used to interacting with. Physics in general can be rather difficult to broach with any amount of detail to people who don't have a major initiative to seek out details on their own.
Plasmas and gases react completely differently to electromagnetic fields and gravity.
This gets at what I was saying in another comment above. Yes, in some situations they react very differently, but in other situations they do not. Plasma vs. gas is not some discrete division, but more of a continuum where the significance of E&M effects vary. Frequently there are times where maybe only electrical effects are significant and not magnetic ones, or even messy situations where such effects are strong enough to mess with the electrons in the plasma, but not directly affect the ions.
Einstein's Relativity was postulated at a time when it was not known that plasma was the universe's preferred state for matter.
This turns out to not be that relevant though, as plasma physics and relativity get along just fine. When in a regime where it matters, there are derivations of relativistic plasma theories, and quite a bit of active research in their application to astrophysical plasmas.
The electric force is 10^39 (or somewhere around there) stronger than the gravitational force
This is true if you just have two charged particles sitting in some vacuum, but the real world is much more nuanced and complicated. As soon as you have multiple particles of opposite charges involved, there are screening processes that can greatly affect the long distance strength of the electric force (e.g. n
By the way, I looked at the thing about the uncertainty in G. Qualitatively, it looks like individual experiments have been reducing uncertainty over the last 10 to 20 years, although not by much more than a factor of 2-5. There seem to be frequent corrections and changes to the errors reported afterwards as they look for other sources of errors. One source of an attempt to integrate various measurements into a value is the CODATA, and this was there relative uncertainty for the last several values of G:
1986 - 1.3e-4
1998 - 1.5e-3
2002 - 1.5e-4
2006 - 1.0e-4
2010 - 1.2e-4
That doesn't look like much of a trend other than a lack of progress. The sudden increase in 98 was attributed to a new experiment that disagreed with previous values, so they kept it in the data they used and kept the larger uncertainty to reflect that there was some contention over the value. Further experiments showed there were some issues with that one experiment, and it was no longer included in later values (although many newer experiments were, even though they have non-overlapping error bars). It looks kind of messy, as even an individual group disagrees when themselves. E.g. a group at Huazhong University of Science and Technology has three results, the first two of which agree, but were both disagreed with CODATA (but were included, ended up being the largest outliers), while their third and newest result agrees with CODATA in addition to having a factor of 5 smaller uncertainty.
Conspicuously absent is any description of what they compare this measurement to, which is just as likely a source of the mistake.