New Class of Stars Are Totally Metal, Says Astrophysicist 119
KentuckyFC writes Stars form when clouds of gas and dust collapse under their own gravity, generating enough heat and pressure to fuse the atoms inside them together. When this cloud of dust and gas is the remnants of a supernova, it can contain all kinds of heavy elements in addition to primordial hydrogen, helium and lithium. Now one astrophysicist has calculated that a recently discovered phenomenon of turbulence, called preferential concentration, can profoundly alter star formation. He points out that turbulence is essentially vortices rotating on many scales of time and space. On certain scales, the inertial forces these eddies create can push heavy particles into the calmer space between the vortices, thereby increasing their concentration. In giant clouds of interstellar gas, this concentrates heavy elements, increasing their gravitational field, attracting more mass and so on. The result is the formation of a star that is made entirely of heavy elements rather than primordial ones. Astrophysicists call the amount of heavy elements in a star its "metallicity". Including preferential concentration in the standard model of star formation leads to the prediction that 1 in 10,000 stars should be totally metal. Now the race is on to find the first of this new class of entirely metal stars.
Look in Decibel Magazine (Score:5, Funny)
or Kerrang! They're full of metal stars
Totally Metal (Score:3, Funny)
When did Nathan Explosion become an astrophysicist?
metal up your ass! (Score:2)
**bangs head**
myNOemail@isSPAMpublic.com (Score:2)
so, i'm supposed to worry about 1337 h4xxxx0rz who have my public email, which I made public, right in my profile?
Re: (Score:2)
Re: (Score:1)
Well, he does wear glasses sometimes.
Made of Led? (Score:3)
Re:Made of Led? (Score:5, Insightful)
name it Ozzy
Re: (Score:2)
Lemmy.
Ouch... (Score:2)
Re: (Score:2)
Re:Hydrogen is metal! (Score:4, Informative)
Helium is not!
If you read the article, however, it would point out that astronomers use a skewed definition of "metal", as any element heavier than lithium.
At birth, stars contain little helium, but is is constantly generated by fusing hydrogen.
If you start with metals like sodium and potassium, plus what we normally call non-metals, like carbon and oxygen, then you won't get around to generating helium until you fuze something radioactive that emits an alpha particle.
Re:Star? (Score:5, Insightful)
Stellar fusion can occur with atomic elements up to iron. There are a number of metals that are lighter than iron. If I'm reading this right, stellar fusion could conceivably be triggered by heavier metallic elements if they were "selected for" by the properties of vortices during the formation process.
Re:Star? (Score:5, Informative)
Additionally, in astrophysics the term "metal" includes many elements which are not metals in any other field. Astrophysically, metals are any element other than hydrogen or helium, so in addition to ordinary metals like sodium and lithium non-metallic elements such as carbon and oxygen are counted as metals.
Re: (Score:2)
To be clear, there are some varying definitions out there from anything other than hydrogen to anything other than hydrogen, helium, or lithium. Other than hydrogen and helium is the definition I've run across most often.
Re: (Score:2)
Re: (Score:2)
The best part of which is that hydrogen is, technically, a metal! (It doesn't act like one in water-based chemistry, but it does in some other contexts.)
Hehe, astonomers, they're in their own world.
Re: (Score:2)
Yep. Carbon, nitrogen, oxygen .. all metals. To an astrophysicist, we're not made of meat, we're made of metal.
(Okay, there's a fair bit of hydrogen in our mix, too.)
Planets rotate around stars (Score:2)
It's not a planet unless it's a planet. And if it's generating radiation through fusion, it's a star of some kind.
Re: (Score:2)
1. In astronomy all the elements except for Hydrogen and Helium are in the category "metals", so no.
2. In astronomy planets are things which orbit stars (plus some other criteria), so no.
Re: (Score:2)
"star stuff" (Score:3)
Every time I hear about a (cool) new kind of star like this i get all teh happi feelz
It reminds me of the Cosmos where Sagan elucidates how everything and everyone we've ever known is made of "star stuff" & our composition reflects our star's composition
So...what kind of planets & planetoids would a **METAL STAR** make???
Re: (Score:1)
Hard Rock, presumably.
Re: (Score:1)
Astrophysicist Dr. Brian May might have some workable theories.
What kind of planet would a metal star make? (Score:2)
Cybertron
We have a name for these already... (Score:5, Funny)
... they're called Class \m/ stars.
Re: (Score:2)
I'd say all we need to do to find the Metal stars is to look for those that have their fusion output turned up to 11.
Metal? (Score:1)
That totally rocks!!!!
Re: (Score:2)
Err, no. None of that is true, and this news doesn't make it any truer.
Re: (Score:2)
No, they really are not. Gravity has very little effect at the atomic level, but at the level of solar systems is the primary force.
Re: (Score:2)
No, they really are not. Gravity has very little effect at the atomic level, but at the level of solar systems is the primary force.
No, they might very well be. But it is just speculation --- accomplished science neither shows whether they are or not. It's just speculation, either way.
Iif you subscribe to the Bohr model of an atom... our solar systems are a larger scale universe's atoms, then the force we call "Gravity" could be the larger scale universe's electromagnetic force, and then Earth
Re: (Score:2)
Re: (Score:2)
Huh? It's been demonstrated many times in many different ways that gravity is by far the weakest of the fundamental interactions. Gravity makes little difference at the atomic and subatomic levels. Atoms are not mini-solar systems. The forces that bind atomic nuclei and bind electrons to atomic nuclei are fundamentally different from gravity. Here's a tip; at least at the temperatures and densities you will find virtually everywhere in the universe today; gravity, electromagnetism, the strong and weak inter
Re: (Score:2)
To see someone making a claim that atoms are mini solar systems in the 21st century isn't too far different from someone claiming the Sun orbits the Earth.
You're either a nasty troll, or you just aren't paying attention at all. The claim was not that atoms are mini solar systems: quite the opposite; that our solar systems themselves are subatomic particles at a grander superscale: a superscale at which our entire solar system weighs something like 3 × 10^-29 grams. And the passage of time from
Re: (Score:1)
One slight problem with that ratio... (Score:5, Interesting)
Hydrogen main sequence stars burn for a a few million years (for the class O supergiants) to literally trillions of years (for the class M all-but-failures). Helium burning, in a star with sufficient mass, lasts between a few hundred thousand to a few dozen million years.
The subject of TFA starts after helium burning normally finishes - Next on a typical star comes carbon, lasting for only a few hundred years; Then comes neon lasting for a single year, oxygen at half a year, and silicon finishes its run in a single day.
So whether or not a star begins life with a high concentration of trans-lithium metals, it will have a very, very short lifetime; That one-in-ten-thousand creation ratio therefore reduces to more like one-in-a-trillion among those stars still shining in our nighttime sky.
Re:One slight problem with that ratio... (Score:5, Funny)
You're right, heavy metal stars usually have short lifespans.
Re: (Score:3)
... Metallica isn't real metal.
Re: (Score:2)
They used to be, then they got inflated as they burned up all the elements that made them in the first place.
Re: (Score:2)
You apparently don't know that Metallica lost a member very early in their career. So, yes, metal stars do flame out early.
Re: (Score:2)
Re: (Score:2)
I know very little of astronomy, but I have to wonder at the reason why each of the fusion cyles is shorter... is it only because some intrinsic property of the heavier fuel? I had alsways assumed that the fact that there is only a fraction of the original star mass that makes it to Carbon, and only a fraction of that to each successive element in the list what the root cause the the exponential decay in life expectancy of each fuel source. If that is the case, the reason that each cycle is shorter is the l
Re:One slight problem with that ratio... (Score:5, Informative)
Fusion of hydrogen into helium produces a LOT of energy. Fusion of helium into carbon produces less. In physics terms, it's the "packing fraction" curve, which can show you what energy you'd get out if you fuse elements together.
Iron is at the bottom of the packing fraction curve; when you fuse other stuff into iron, you're getting out the dregs of the fusion energy, partly because it takes higher and higher pressures and temperatures for fusion to occur for heavier elements.
When you get to the pressure and temperature points where iron fuses into still heavier elements, it begins to EXTRACT energy - from the core of the star. Stars exist in a delicate balance between the heat and pressure that tries to blow them apart, and the gravity that tries to crush them together. Take heat OUT of the core of the star, and there's less internal pressure - and gravity starts to win. The core will collapse, generally abruptly, and a crushing "rebound effect" will accelerate the heavy fusion, extracting MORE energy, leading to a core collapse supernova. The star explodes, leaving a black hole or pulsar at the center and blasting a lot of the stellar material back into space.
Which is where we got the iron for our blood, or the gold for our jewelry - blasted out of a supernova. Probably MANY of them.
Re: (Score:1)
Re: (Score:1)
Re: (Score:1)
Re: (Score:1)
Using a different definition of "metal" (Score:5, Informative)
What astronomers mean for the word "metal" isn't what the rest of us mean.
As mentioned in the link to Metallicity, the all metal stars could be composed of carbon, nitrogen, oxygen, etc. Basically anything other than hydrogen and helium.
Isnt Hydrogen a Metal? (Score:2)
Imploding stars? (Score:1)
At first I thought this was about Justin Bieber.
Re: (Score:2)
Leave your hearing aids at home . . .
Re: (Score:2)
The Logan-Preston.Esq. class star? (Score:2)
*Air Guitar*
Re: (Score:2)
I'll do my bhttp://slashdot.org/comments.pl?sid=5360761&cid=47380539#est to keep it tucked back.
Heavy (Score:2)
Now that's heavy metal I could actually get into...
Fission? (Score:2)
Um.. but no energy could be released from such a star surely, since fusion of anything heavier than iron produces no energy, but actually takes energy. The only way it could produce energy then would be fission. But I'm skeptical about whether a star in such circumstances would really light up, or would just be a sphere of dead metal.
Re: (Score:2)
Right, iron Fe, atomic mass 26.
Lithium, for instance, has an atomic mass of 3. Lithium is a metal. I'm sure there are other metals below 26, Sodium comes to mind (atomic mass of 11).
So, based on the assumption that heavier than iron means fission, but less than iron fusion, there's still room for fusion, no?
I think this is fusion, but with a slightly different chemistry, but then the
Re: (Score:2)
In fact, the fusion of anything that produces an element heavier than iron will extract energy from the star's core, hastening its collapse.
Re: (Score:2)
Wow, a Lithium powered sun, that's pretty cool. :-P
It sure as hell wouldn't be depressed.
Such as a "Death Star" perhaps? (Score:2)
And we'll name the first one we find Black Sabbath (Score:4)
Unless it's made of a light metal...then we'll name it Warrant.
Implication for stellar clusters (Score:3)
If I'm reading TFA correctly, it basically means that stars formed from one molecular cloud have very different metallicities - anywhere between the mean metallicity of the molecular cloud and the "purely metal" extreme. If this is actually true, there may be far reaching implications for the research of stellar clusters. One of the basic assumptions in this field is that all cluster stars created from a given molecular cloud have very similar chemical compositions.
Not the Usual Definition of Metal (Score:5, Informative)
In astrophysics, the term "metal" normally applies to any element heavier than lithium. Carbon, silicon, even gasses like oxygen and nitrogen, are "metals". We're not talking about star remnants that are primarily iron or lead or uranium. Gold would be right out.
Re: (Score:2)
So - no gold star... Oh well :-)
Re: (Score:2)
Re: (Score:2)
The iron doesn't "want" to come apart, and doesn't.
The star is a fine balance of gravitational attraction that compresses of all its parts to the point of fusion at the center, and the expansion of the star as the pressure of fusing energy at the center wants to expand the star.
At first, hydrogen is converted to helium and that process is so energy-rich that the star doesn't struggle much to hold off the collapsing effect of gravity.
As other elements are converted from one to the other, the fusion process i
Pinball (Score:2)
We have yet to find a star with this spectrum (Score:4, Interesting)
And we have been studying stellar spectra for a century now. The must be much rarer than 1 in 10,000 or we would have already found one. They must be exceedingly rare.
Re: (Score:2, Interesting)
How would you spot them? The stellar spectra you mention are visible because of all the energy that a non-metallic star can generate through fusion. But metal stars don't have that energy available. They'll be dim, which affects the distance at which we can spot them. The lack of light also complicates our ability to determine their spectra. So the fraction of metal stars amongst the stars with a known spectrum will be even lower than that 1:10000.
Stellar Alchemist (Score:1)
Totally Metal stars? ROCK! (Score:2)
I expected the astrophysicist to be Queen guitarist Brian May...