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Milky Way Is Surrounded By Halo of Hot Gas

Unknown Lamer posted about 2 years ago | from the fog-from-insufficient-rendering-power dept.

Space 121

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."

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1,000,000 K ?!? (1)

ackthpt (218170) | about 2 years ago | (#41443793)

Iiiii'm the CAT!

Seriously, we're not going to get out of this galaxy alive.

WHO SMELT IT? (-1, Offtopic)

Jeremiah Cornelius (137) | about 2 years ago | (#41443827)

Dealt it. Word.

Re:1,000,000 K ?!? (0, Offtopic)

Jeremiah Cornelius (137) | about 2 years ago | (#41443849)

here in the technical vastness of The Future, we can guess that surely, the past was very different. We know for certain, for instance, that for some reason, for some time in the beginning, there were hot lumps. Cold and lonely, they whirled noiselessly through the black holes of space.

Re:1,000,000 K ?!? (2, Funny)

Jeremiah Cornelius (137) | about 2 years ago | (#41443861)

These insignificant lumps came together to form the first union, our sun, the heating system. And about this glowing gas bag, rotated the Earth, a cat's eye among aggies, blinking in astonishment across the face of time.

Re:1,000,000 K ?!? (3, Funny)

Jeremiah Cornelius (137) | about 2 years ago | (#41443881)

Well, we were covered with a molten scum of rocks, bobbing on the surface like rats. Later, when there was less heat, these giant rock groups settled down among the land masses. During this extinct time, our Earth was like a steam room, and no one, not even man, could get in. However, the oceans and the sewers were simmering with a rich protein stew, and the mountains moved in to surround and protect them. They didn't know then that living as we know it was already taking over.

Re:1,000,000 K ?!? (2, Funny)

Jeremiah Cornelius (137) | about 2 years ago | (#41443893)

Animals without backbones hid from each other, or fell down. Clamosaurs and oysterettes appeared as appetizers. Then came the sponges, which sucked up about 10% of all life. Hundreds of years later, in the Late Devouring Period, fish became obnoxious. Trailerbites, chiggerbites, and muskquitoes collided aimlessly in the dense gas. Finally, tiny, edible plants sprang up in rows, giving birth to generations of insecticides and other small, dying creatures.

Re:1,000,000 K ?!? (3, Funny)

Jeremiah Cornelius (137) | about 2 years ago | (#41443903)

Millions of months passed, and, 28 days later, the moon appeared. This small change was reflected best, perhaps, in the sand dollar, which shrank to almost nothing at the bottom of the pool, where even dumb amphibians like catfish laid their eggs in the boiling waters, only to be gobbled up every three minutes by the giant sea orphans and jungle bunnies, which scared everybody. And so, IN FEAR AND HOT WATER, MAN IS BORN!!!

Re:1,000,000 K ?!? (3, Funny)

MyLongNickName (822545) | about 2 years ago | (#41444297)

What are you talking about, Bozo?

Re:1,000,000 K ?!? (0)

Jeremiah Cornelius (137) | about 2 years ago | (#41444359)

"This is worker speaking. Hello."

"Why does the poor rich Barney (honk) delay laser's edge in the fair?"

Re:1,000,000 K ?!? (1)

MyLongNickName (822545) | about 2 years ago | (#41444797)

(shuts down)

Re:1,000,000 K ?!? (1)

fustakrakich (1673220) | about 2 years ago | (#41445389)

"I think he broke the President!"

Re:1,000,000 K ?!? (3, Interesting)

ackthpt (218170) | about 2 years ago | (#41443895)

here in the technical vastness of The Future, we can guess that surely, the past was very different. We know for certain, for instance, that for some reason, for some time in the beginning, there were hot lumps. Cold and lonely, they whirled noiselessly through the black holes of space.

This is making me feel like there's a big game going on.

You'll never escape gravity!

OK, you escaped gravity, but you'll never survive the Van Allen Radiation Belt!

OK, you passed through the Van Allen Radiation Belt, but you'll never make it through the Asteroid belt!

OK, you successfully navigated the Asteroid belt, but you'll never make it through the Kuiper belt!

Dang, you made it through the Kuiper belt, but you'll never, ever make it through the Baryon Halo! Muah ha ha ha haaaah!

Re:1,000,000 K ?!? (2, Funny)

Jeremiah Cornelius (137) | about 2 years ago | (#41444095)

"No, Mr. Bond. I expect you to die."
-- Auric Goldfinger

Re:1,000,000 K ?!? (2)

MyLongNickName (822545) | about 2 years ago | (#41444319)

And if that doesn't work, at least we can keep you humans confined by the whole speed of light thing.

Re:1,000,000 K ?!? (0)

Anonymous Coward | about 2 years ago | (#41447235)

Working on it: http://www.nasa.gov/centers/glenn/technology/warp/ideachev.html

But don't hold your breath.

Re:1,000,000 K ?!? (1)

jellomizer (103300) | about 2 years ago | (#41447989)

Even with the speed of light broken, the Galaxy is still very very very big.

100,000 Light years Diameter. From my understanding the Theoretical model says we can probably go 10x the speed of light. Meaning that it will still take 10,000 years at 10x speed of light. Heck if you use the Speed of Plot that Star Trek and other Sci-Fi uses, it still takes about 100 years just to cross the galaxy.

Just to give you an idea of size. Star Trek Seems Warp drive seems to have an average of 1000x the speed of light. that means it will take 36 hours to get from Earth to Alpha Proxima.

That is still about 545 Are we there yets.

Re:1,000,000 K ?!? (1)

MyLongNickName (822545) | about 2 years ago | (#41448983)

From my understanding the Theoretical model says we can probably go 10x the speed of light

You piqued my curiosity. Where can I read more about this?

Re:1,000,000 K ?!? (1)

tehcyder (746570) | about 2 years ago | (#41449833)

From my understanding the Theoretical model says we can probably go 10x the speed of light

You piqued my curiosity. Where can I read more about this?

He could tell you, but then he'd have to kill you.

Re:1,000,000 K ?!? (0)

Anonymous Coward | about 2 years ago | (#41444887)

Remind anyone of the plot behind Solar Winds [mobygames.com] ?

Re:1,000,000 K ?!? (0)

Anonymous Coward | about 2 years ago | (#41446069)

Oh yeah! I knew there was something familiar about the idea. Also, that game was fun!

Re:1,000,000 K ?!? (0)

Anonymous Coward | about 2 years ago | (#41447157)

You could always fly northways.

Re:1,000,000 K ?!? (5, Informative)

jamesh (87723) | about 2 years ago | (#41444147)

Depends on how dense it is. If you immerse yourself in water at 100C (boiling point for you imperial scumdogs :) you won't last long at all, but in dry air at 100C you can survive for substantially longer. If the gas was so sparse that you might only hit a molecule every few seconds or so then the temperature might not matter so much. The article hints that the density is low "The estimated density of this halo is so low that similar halos around other galaxies would have escaped detection." but that doesn't really help in absolute terms.

(or maybe you're making a joke... i don't get the reference in the first line you posted)

Re:1,000,000 K ?!? (1)

canadian_right (410687) | about 2 years ago | (#41446027)

mod up, this is very informative.

Re:1,000,000 K ?!? (1)

kasperd (592156) | about 2 years ago | (#41444159)

Seriously, we're not going to get out of this galaxy alive.

We are not. But our descendants might. I think that gas is the least problem when leaving the galaxy. It might be hot, but if it isn't very dense, then that might not matter.

Re:1,000,000 K ?!? (3, Funny)

X0563511 (793323) | about 2 years ago | (#41449007)

but if it isn't very dense, then that might not matter.

That was perhaps the best worst pun ever.

Re:1,000,000 K ?!? (1)

davester666 (731373) | about 2 years ago | (#41446841)

Great. This will be something else for our Congressmen to boast about as a "We worked hard to accomplish this."

Hot gas (1)

Ultra64 (318705) | about 2 years ago | (#41443801)

Excuse me.

Re:Hot gas (1)

MightyYar (622222) | about 2 years ago | (#41445447)

Woah... I can't believe you had the exact same thought as me... crazy.

Wha? (2)

Anonymous Coward | about 2 years ago | (#41443857)

that envelopes the galaxy

Surely you meant to use the verb, i.e. "envelops".

Re:Wha? (5, Funny)

Sulphur (1548251) | about 2 years ago | (#41444061)

that envelopes the galaxy

Surely you meant to use the verb, i.e. "envelops".

Forming a letter of galactic proportions without a stamp.

Re:Wha? (1)

Quirkz (1206400) | about 2 years ago | (#41449241)

I'm loathe to pointe out you're being too rationale about this, and the mounting criticism is bad for moral.

There are also.... (-1)

i_want_you_to_throw_ (559379) | about 2 years ago | (#41443875)

dark brown rings around Uranus.

Re:There are also.... (0)

Anonymous Coward | about 2 years ago | (#41448073)

They have bleaching for that.

Warm Gas (1)

Todamont (1034534) | about 2 years ago | (#41443889)

"... a few hundred times hotter than the surface of the sun." That's very warm.

Re:Warm Gas (1)

ackthpt (218170) | about 2 years ago | (#41444105)

"... a few hundred times hotter than the surface of the sun." That's very warm.

It's relative warmth in the 100,000 K and up club it's rather difficult to keep track because once you've boiled away Tungsten, there's not much meaning in additional units of heat.

It does give me the impression the galaxy is actually protecting us from all this hot matter, it gets too close and gets blown away by a star or attacted to cooler matter. I imagine, however, this halo should be generating some serious amounts of IR. Need that ol' James Webb telescope to explain more about it.

Re:Warm Gas (3, Informative)

mister_playboy (1474163) | about 2 years ago | (#41445835)

It's relative warmth in the 100,000 K and up club it's rather difficult to keep track because once you've boiled away Rhenium, there's not much meaning in additional units of heat.

https://en.wikipedia.org/wiki/Rhenium [wikipedia.org]
The more you know... :)

Re:Warm Gas (1)

hvm2hvm (1208954) | about 2 years ago | (#41447057)

I spent 30min on Wikipedia because of you...

Poul Anderson (0)

Anonymous Coward | about 2 years ago | (#41443891)

Lets hope it's just hot gas instead of an energy dampening field like in Poul Anderson's Brain Wave story.

How does something so un-dense... (1)

Nutria (679911) | about 2 years ago | (#41443995)

retain it's 1,000,000K for 14,000,000 years?

Re:How does something so un-dense... (5, Informative)

radtea (464814) | about 2 years ago | (#41444151)

retain it's 1,000,000K for 14,000,000 years?

First, that's 14,000,000,000, not 14 million.

The key is how undense it is. When a physicist talks about "temperature" in this context it's just short-hand for "average velocity"... it doesn't necessarily imply thermal equilibrium, even. So 1e6K means a high average velocity. Now, if it were a dense gas there might be collisions that would do things like excite electrons into higher states, which would then decay by emitting photons (light), and so the gas would lose thermal-kinetic energy over time.

In a sufficiently diffuse gas, loss processes like this are very slow because the chances of collision are very slow, so it can stay "hot" (that is, have a high average velocity) for a long, long time.

Re:How does something so un-dense... (1)

Nutria (679911) | about 2 years ago | (#41444273)

First, that's 14,000,000,000, not 14 million.

I realized that afterwards...

When a physicist talks about "temperature" in this context it's just short-hand for "average velocity"... it doesn't necessarily imply thermal equilibrium, even.

Huh? "Temperature" isn't that much easier to write, say or think about than "average velocity".

Re:How does something so un-dense... (5, Informative)

bughunter (10093) | about 2 years ago | (#41444453)

Temperature (in Kelvin) is actually more useful in astrophysics and thermodynamics of plasmas. It wraps up a bunch of messy real world constants into one number, and also neatly describes the behavior of the volume of gas as a whole, rather than forcing the analyst to perform a lot of messy integrating and averaging of distributions of actual velocities in three dimensions.

Think about it this way. No one is really interested in how fast a specific particle is moving. They're more interested in how the Thermal Energy of the gas couples with other systems.

A galactic halo would be coupled very, very, (very^18) poorly with other systems, at least conductively. And probably even worse convectively, given the scales involved. Radiatively, I don't know near enough about the behavior of these particles to talk about why, but if it's stayed that hot for the life of the universe, effectivelt, then apparently its either not coupled to another system, coupled far more strongly to itself than anything else, or somehow not stimulated to emit blackbody radiation... or all three of the above.

Re:How does something so un-dense... (2)

slew (2918) | about 2 years ago | (#41444929)

On the other hand Temperature (e.g., in Kelvin) is only marginally useful in describing the distribution of a phenomena that isn't in thermal equilibrium (say non-blackbody radiation)...

For example, people used to grade lightbulbs by their color Temperature, but that didn't say much about the quality of illumination from said lightbulb. Now they use CRI (color rendering index) for lightbulbs which give some information about the actual distribution instead of the really poor assumption that the illumination was comparable to black-body radiation distribution.

It's not clear (to me) that a galactic halo would necessarily be in thermal equilibrium, except only approximatly over a long time horizon. The real interesting observable phenomena is likely a result of this not being true (e.g. http://arxiv.org/abs/1106.4816 [arxiv.org] )

Re:How does something so un-dense... (1)

Rich0 (548339) | about 2 years ago | (#41446031)

I don't think it has been this hot for the entire life of the universe - it actually hot hotter with time most likely. This was likely gas found in intergalactic space that fell gravitationally towards the milky way. After falling for billions of years it is moving really fast. However, the gas is so sparse that there really aren't any collisions to speak of. Sure, if a particle hits a star or planet or something that will stop it, but chances are this stuff is hitting our atmosphere all the time, but for every particle that hits the earth trillions pass all around us flying through the solar system and the space beyond at incredible velocity.

Re:How does something so un-dense... (2)

PvtVoid (1252388) | about 2 years ago | (#41444449)

When a physicist talks about "temperature" in this context it's just short-hand for "average velocity"... it doesn't necessarily imply thermal equilibrium, even. So 1e6K means a high average velocity. Now, if it were a dense gas there might be collisions that would do things like excite electrons into higher states, which would then decay by emitting photons (light), and so the gas would lose thermal-kinetic energy over time. In a sufficiently diffuse gas, loss processes like this are very slow because the chances of collision are very slow, so it can stay "hot" (that is, have a high average velocity) for a long, long time.

Uh, no. If the collision rate weren't high enough to excite electrons into higher states, it wouldn't be radiating X-rays, which is how Chandra detects the gas. Not a whole lot is known about gas in halos like the Milky Way's, but clusters have been extensively studied, and the gas is pretty close to thermal equilibrium [caltech.edu] , but not exactly. Hot cluster halos are ubiquitous, and it's not terribly surprising that more isolated galaxies have hot halos as well. The gas heats from loss of gravitational potential when it falls into the halo, and it stays hot because there are few cooling mechanisms, and because subsequent infall [arxiv.org] repleneshes it.

Re:How does something so un-dense... (3, Informative)

Anonymous Coward | about 2 years ago | (#41444559)

If the collision rate weren't high enough to excite electrons into higher states, it wouldn't be radiating X-rays, which is how Chandra detects the gas.

Chandra isn't seeing X-ray emissions from the gas, it's seeing X-rays being absorbed by the gas. Specifically, observing 8 X-ray sources hundreds of millions of light-years beyond the gas, it was discovered that some of the X-rays from those sources were being absorbed, and it was possible to deduce the temperature of the absorbing gas.

Re:How does something so un-dense... (2)

PvtVoid (1252388) | about 2 years ago | (#41444629)

Chandra isn't seeing X-ray emissions from the gas, it's seeing X-rays being absorbed by the gas. Specifically, observing 8 X-ray sources hundreds of millions of light-years beyond the gas, it was discovered that some of the X-rays from those sources were being absorbed, and it was possible to deduce the temperature of the absorbing gas.

Whoops. My bad, [nasa.gov] But my point still stands: the light is being absorbed by oxygen ions at a temperature of a million Kelvin: what do you think is ionizing them?

When people refer to temperatures in a galactic halo, they absolutely mean to imply that the halo is somewhere close to thermal equilibrium.

Re:How does something so un-dense... (1)

Shavano (2541114) | about 2 years ago | (#41445801)

Let's see. At the average thermal velocity of

v = sqrt(3 kT/m) ; where m = 1.66E-27 k = 1.38E-23 T = 1E6 so v = 158 km/sec?

What's the escape velocity of a particle in this halo?

Escape velocity (1)

maroberts (15852) | about 2 years ago | (#41447203)

Let's see. At the average thermal velocity of

v = sqrt(3 kT/m) ;
    where m = 1.66E-27
    k = 1.38E-23
    T = 1E6
    so
            v = 158 km/sec?

What's the escape velocity of a particle in this halo?

Somewhere close to the airspeed velocity of an unladen swallow (European)

Re:How does something so un-dense... (0)

Anonymous Coward | about 2 years ago | (#41448155)

Assuming a mass of the particles between 1 and 10x the mass of a proton we're talking around 600 to 6000 ms/s for 1mK. Well below the escape velocity of the galaxy.

Re:How does something so un-dense... (1)

rgbatduke (1231380) | about 2 years ago | (#41448393)

Yeah, I'm having a few problems with the idea. Temperature actually implies thermal equilibrium, which in turn requires interaction. However, those atoms/molecules are, shall we say cosmicly non-interacting, being so dispersed that they basically form a hard vacuum. There are then a number of problems with the picture. One, why do the molecules not simply fall back into the galaxy (or if you like, why were they pushed out of the galaxy in the first place)? Several billion years accumulation of solar wind and outflow from supernovae? Second, why don't they "cool" to equilibrium with the background blackbody radiation? That one at least is answerable -- they basically never collide (as you say). The third question is -- how can one detect the gas? The molecules are cold, non-interacting, and enormously diffuse. To the extent that they interact with photons, they would relatively quickly slow down to equilibrium, so they are almost by definition invisible. Furthermore, photons are photons, and being a gas detecting the origin of a photon approaching the Earth from any given direction (that is, the distance of the source) is quite impossible, ditto for absorption lines from distant stars. I mean, parallax won't work. Neither will red shift. Alterations of gravity (as in the way one infers "Dark Matter") might work, but won't give you the speed or "temperature" or ensure that the matter that is altering orbits is a gas of baryons as opposed to darkonium.

Indeed, the title is horribly misleading. It would be better to say that the galaxy may be surrounded by a very diffuse gas of particles at a very low temperature in a reference frame that has a very high velocity relative to the galactic core, and we infer this compared to all competing explanations by sacrificing a chicken with a black-handled knife on the keyboard of a computer.

rgb

Re:How does something so un-dense... (0)

Anonymous Coward | about 2 years ago | (#41449515)

Even at a density of one particle per cubic meter, with a temperature of around 100 eV, you would get several collisions a day. That is more than enough to get a thermal distribution over long time periods.

Re:How does something so un-dense... (1)

camperdave (969942) | about 2 years ago | (#41444515)

Temperatures of near vacuum gasses are not the same as temperatures of gasses at higher pressures. You can't just stick a thermometer in and see what it reads. What you do is measure the kinetic energy of individual gas particles, and back-calculate to find out what temperature a regular gas would have in order that its average molecule would have the same kinetic energy. In the vacuum of intergalactic space, the individual gas particles can have tremendous kinetic energy, and they are likely to keep that energy because there is nothing to bounce off of.

Re:How does something so un-dense... (1)

Nutria (679911) | about 2 years ago | (#41444729)

What you do is measure the kinetic energy of individual gas particles, and back-calculate to find out what temperature a regular gas would have in order that its average molecule would have the same kinetic energy.

That's an indirection too far to pass the smell test.

Re:How does something so un-dense... (0)

Anonymous Coward | about 2 years ago | (#41444803)

Temperature of plasmas is the same as temperature of just about any other system, especially gases. In both cases temperature relates to the average kinetic energy of the particles minus bulk, center of mass movement (.. and ultimately in all cases temperature's definition relates back to the partition function of the system). Even though you can't just stick a thermometer in it, they both have distributions of particle speeds, which both tend to a thermal equilibrium distribution, although sometimes you can find situations where they haven't settled yet. If you have enough of either to be optically thick, you still get the same blackbody radiation emissions appropriate to their temperatures. Probably the only place gas temperatures get a little more complicated is when out of equilibrium, where rotational, vibrational, and translation motions of molecules all have separate temperatures that haven't equilibrated

Re:How does something so un-dense... (1)

nedlohs (1335013) | about 2 years ago | (#41445819)

By being "un-dense". How do you propose for the kinetic energy to be removed?

Re:How does something so un-dense... (1)

Rich0 (548339) | about 2 years ago | (#41446063)

It likely only got hotter with time - as it fell towards the galaxy and picked up speed. In order to lose temperature the gas molecules have to actually interact with something. There isn't anything for them to interact with - these things are flying through intergalactic space basically flying around the galaxy.

Put hot water in a thermos and it stays hot for a while. Put hot water in intergalactic space and it stays hot for much longer. However, the water molecules still interact and release photons out into space radiatively. Ionized hydrogen is just loose protons flying through space - they don't just emit photons, and neither do free electrons as far as I'm aware. When they occasionally collide then you get photons released as x rays, which is what gets imaged.

I think most of the mass of the universe actually exists as these clouds of gas surrounding superclusters.

Re:How does something so un-dense... (0)

Anonymous Coward | about 2 years ago | (#41446849)

Free charged particles will emit synchrotron radiation when undergoing any acceleration. If they were orbiting around a gravitational center of mass, they would eventually radiate away energy until they were the same temperature as the CMB even without collisions. The timescale for such processes would be pretty large unless you have high temperature collisions though. Additionally, a bunch of particles just orbiting the galaxy wouldn't really be well described by a temperature, as that would be a non-thermal equilibrium of velocity distributions, so they would need some collisions or interactions to just thermalize in the first place.

Calculate the acceleration at that distance. (0)

Anonymous Coward | about 2 years ago | (#41447339)

Go on, I dare you.

Re:Calculate the acceleration at that distance. (0)

Anonymous Coward | about 2 years ago | (#41448571)

1.8e-11 m/s^2 [google.com]

And power loss from synchrotron radiation at that acceleration 4e-49 eV/year [google.com] .

As said, that results in a very long timescale by itself. But if there are any collisions, the acceleration is much, much, higher and the gas will slowly radiate power on astronomical timescales. And there is or was collisions at some point if the gas has a thermal distribution.

Galactic Barrier (5, Interesting)

wonderboss (952111) | about 2 years ago | (#41444071)

Re:Galactic Barrier (0)

Anonymous Coward | about 2 years ago | (#41444125)

Once again, Roddenberry was right!

Slashdot was right all along.... (0)

Anonymous Coward | about 2 years ago | (#41445613)

My first glance at the thread title, I thought it said: Milky Way is Surrounded by a Halo of Hot Grits :D

Personally... (1)

Tarlus (1000874) | about 2 years ago | (#41444099)

...I think you guys just like saying the word "baryon".

Re:Personally... (0)

Anonymous Coward | about 2 years ago | (#41445443)

:)@sig

Halos? (0)

Anonymous Coward | about 2 years ago | (#41444123)

Dammit we we're supposed to meet The Covenant for about another 530 years!

Wait (2)

Charliemopps (1157495) | about 2 years ago | (#41444157)

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...

Re:Wait (4, Informative)

PvtVoid (1252388) | about 2 years ago | (#41444471)

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...

It has been known for a long time that the intergalactic medium is hot enough to be ionized [ua.edu] . That part is not news. The thing that's news is that the hot gas makes it possible to account for the baryons in the Milky Way halo, which were previously undetected.

Re:Wait (4, Interesting)

waveclaw (43274) | about 2 years ago | (#41446165)

The thing that's news is that the hot gas makes it possible to account for the baryons in the Milky Way halo, which were previously undetected.

The thought that we're just the 0.1% of the dirty precipitate at the bottom of the gravity well is a tad humbling. Not that much isn't when you look up from the T.V. to a clear night sky.

Galaxies are apparently quite dynamic things: a rain of in-falling gas to make new stars, pressure from new stars pushing back, dust build up from all this nucleosynthesis, blackhole cores that cycle on and off. One paper I read even claims this is the beginning of the 'green' period for the Milky Way. The conditions for life will be come more abundant: the number of long-burning dwarf stars like the sun continue to rise as a fraction of the stellar population while the dust percentage (you know, planets) rises at the same time a lot of the big super- and hyper- novae are over with.

However, longer term prospects seem bleak if the dynamic gas is all consumed or blown away. Eventually stellar production would grind to a halt. The green galaxy would give way to white and red dwarfs floating amid other stellar corpses and thinned gas.

I have to wonder if the temperature and environmental coupling of this gas is enough to become a future raw star material resource? I mean, we're talking about 99.9% of the matter here and it's already gravitationally bound. Could someone model long-term in-fall of this ionized matter? Could it cool fast enough or even at all to beat the predicted 'big rip' from dark energy and give the galaxy a 2nd, 3rd, etc. childhood?

Re:Wait (0)

Anonymous Coward | about 2 years ago | (#41447435)

The thought that we're just the 0.1%...

And I thought we were the 99%!

Re:Wait (2)

Tom (822) | about 2 years ago | (#41447727)

and is 300,000 lightyears across... possibly extending far into other galaxies...

You are vastly underestimating galactic distances. Our closest neighbor, Andromeda, is over 2 million light years away.

Re:Wait (1)

tehcyder (746570) | about 2 years ago | (#41450013)

and is 300,000 lightyears across... possibly extending far into other galaxies...

You are vastly underestimating galactic distances. Our closest neighbor, Andromeda, is over 2 million light years away.

Yeah, and we don't even get on that well.

halo of hot gas? (2)

DJCouchyCouch (622482) | about 2 years ago | (#41444185)

Sorry, that was me. BIG burrito last night.

Hot gas is a plasma, but nobody here seems to care (0)

Anonymous Coward | about 2 years ago | (#41444211)

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 ...

Re:Hot gas is a plasma, but nobody here seems to c (4, Interesting)

Anonymous Coward | about 2 years ago | (#41444333)

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.

Re:Hot gas is a plasma, but nobody here seems to c (1)

tragedy (27079) | about 2 years ago | (#41445001)

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.

Re:Hot gas is a plasma, but nobody here seems to c (1)

Anonymous Coward | about 2 years ago | (#41445477)

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.

Re:Hot gas is a plasma, but nobody here seems to c (0)

Anonymous Coward | about 2 years ago | (#41448005)

Me? I'm a plasma psychologist. I watch TV and help the people on it.

Re:Hot gas is a plasma, but nobody here seems to c (0)

Anonymous Coward | about 2 years ago | (#41448905)

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."

So Star Trek had it right? (3, Interesting)

Bomarc (306716) | about 2 years ago | (#41444213)

Re:So Star Trek had it right? (1)

Anonymous Coward | about 2 years ago | (#41449519)

No. The Galactic Barrier is a (fictional) force field around our galaxy, preventing matter to get out or in (supposedly placed there by some higher intelligence).

The real thing is a very sparse cloud of ionized gas. It doesn't work like a barrier at all.

Re:So Star Trek had it right? (1)

tehcyder (746570) | about 2 years ago | (#41450057)

No. The Galactic Barrier is a (fictional) force field around our galaxy, preventing matter to get out or in (supposedly placed there by some higher intelligence). The real thing is a very sparse cloud of ionized gas. It doesn't work like a barrier at all.

You really are a bundle of fucking laughs aren't you?

Not dark matter (1)

Anonymous Coward | about 2 years ago | (#41444365)

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,

Nothing to do with Dark Matter (2)

mbone (558574) | about 2 years ago | (#41444625)

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.)

Hang on... (0)

Anonymous Coward | about 2 years ago | (#41444711)

If the galaxy is surrounded by a halo of incredibly hot gas, wouldn't this put a damper on any kind of intergalactic travel?

Re:Hang on... (1)

mbone (558574) | about 2 years ago | (#41444865)

No, no more than the incredibly hot solar corona / wind bothered the Apollo astronauts. The energy density is just way too low.

Re:Hang on... (1)

tragedy (27079) | about 2 years ago | (#41445061)

It's hot, but it's also a hard vacuum. For a spacecraft travelling through it, it's probably better to just think of it as radiation.

Wow... (4, Funny)

luckymutt (996573) | about 2 years ago | (#41444825)

...has Rush Limbaugh really gotten that big?

Re:Wow... (0)

Anonymous Coward | about 2 years ago | (#41445985)

Does ego count?

Re:Wow... (0)

Anonymous Coward | about 2 years ago | (#41449687)

Nah, that's Obama's reality distortion field.

What is this Stellar Hot Air Day? (1)

Pyrus.mg (1152215) | about 2 years ago | (#41445129)

The previous story is the Romney-Ryan Space Policy.

Gene Roddenberry was right (1)

greg_barton (5551) | about 2 years ago | (#41445461)

There is a barrier [memory-alpha.org] surrounding the galaxy!

3 Degree Kelvin Says NO! (0)

Anonymous Coward | about 2 years ago | (#41445727)

Me thinks this is another unfortunate 'Oh Shit ... I Ate The Fucking Data' again.

Oh well ... nice try by the ... 'authors' of this phantasmagoria.

That's just stupid. (1)

Shavano (2541114) | about 2 years ago | (#41445843)

Everyone knows a Milky Way is surrounded by a halo of milk chocolate.

hmm (0)

Anonymous Coward | about 2 years ago | (#41446481)

no...chocolate

NO STEM = ANJALI GUPTA BACK HOME. (0)

Anonymous Coward | about 2 years ago | (#41447089)

Signed /Troll

These are the farts... (0)

Anonymous Coward | about 2 years ago | (#41447241)

of the Great A'Tuin

Name two things... (1)

Genda (560240) | about 2 years ago | (#41447387)

Surrounded by a halo of hot gas... The Milky Way Galaxy and Washington D.C.

"OMG, if's full of"..... (0)

Anonymous Coward | about 2 years ago | (#41447765)

GAS!

Life the universe and everything (0)

Anonymous Coward | about 2 years ago | (#41449913)

Looks like the universe is lactose intolerant...

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