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The Sun Had Sisters
[TheBORG] writes to mention a Space.com article about the Sun's departed solar siblings. Our own medium-sized yellow star was far from alone when it was formed, with hundreds of fellow solar bodies and a supernova to keep it company. From the article: "The evidence for the solar sisters was found in daughters--such as decayed particles from radioactive isotopes of iron--trapped in meteorites, which can be studied as fossil remnants of the early solar system. These daughter species allowed Looney and his colleagues to discern that a supernova with the mass of about 20 suns exploded relatively near the early Sun when it formed 4.6 billion years ago; and where there are supernovas or any massive star, you also see hundreds to thousands of sun-like stars, he said. The cluster of thousands of stars dispersed billions of years ago due to a lack of gravitational pull, Looney said, leaving the sisters 'lost in space' and our Sun looking like an only child ever since, he said."
They were doing the Nutron Dance....woooohooo...
DEAD DEAD DEAD DELETE ME
...but an appropriate name for an astrophysicist.
Pah, evidence. Faith and internal revelation is a much more powerful "way of knowing." Look at me! I'm an epistomologist!
A guy named Looney is trying to tell us the Sun had sisters.
Sigs are for Terrorists.
I bet they were hot!
HA! The sun would have to get up *PRETTY EARLY IN THE MORNING* to catch *ME* out"!!!
Oh wait...
Gentoo Linux - another day, another USE flag.
This is pure crap I'm spittin out here, but I suppose anything is possible...
So it's slightly possible that George Lucas wasn't lying and the whole galactic-terran-empire "long-long ago" thing really happened?
In all seriousness though (well, half seriousness), suppose this would mean that Earth IS that bunch of humans huddled around a burning-trash-can of a black-hole?
Let me see if I have this clear now. We are mold forming upon the scum on top of a molten pile of rock swinging around a hot piece of miniscule debris left over from a single speck exploding on the outskirts of a tiny disk floating in a vast space full of other tiny disks and whatnot? And the going theories include one where this vast space is only one of an infinite number of vast spaces?
Put's watching my diet in perpective, that's for certain.
You are checking your backups, aren't you?
'Interplanetary lesbian incest and its place in the formation of our galaxy'
So the claim is that hundreds, maybe thousands, of sun-like stars were in close proximity to each other, but they didn't generate enough gravity to stay in the same neighborhood? How does that make any kind of sense?
God invented whiskey so the Irish would not rule the world.
No, the areas wher you find the massive and super massive starts that can go nova usually have lots of sun sized stars also. The solar system was bombarded by the debris from a nearby super nova early in its life, ergo it was part of a stellar cluster.
"The cluster of thousands of stars dispersed billions of years ago due to a lack of gravitational pull, Looney said"
How does that work? These stars are the gravitational pull, local "depressions" in the spacetime fabric that bend space around them towards themselves. Which is gravitational pull. Which must be overcome by some other force, either other gravitational pull from some other, larger/closer mass(es), or momentum from a kinetic event like a collision. Maybe the exploding supernova knocked them out of the area. Maybe, if it was big enough, its departing mass would have not only knocked the stars away, but pulled them away, overcoming their mutual gravitational attraction through greater departing, but still attractive, mass.
But something did. That's the biggest missing factor in this whole proposed scenario, in Robin Lloyd's Space.com story about it at least, that it needs to hold it together. Theories fall apart because of a lack of gravity, star clusters not so much.
--
make install -not war
Danger. Do not post while you have a burger in your hand and the music blaring otherwise you may spell as poorly as I did in the previous post.
TFA said "a supernova with the mass of about 20 suns exploded relatively near the early Sun when it formed 4.6 billion years ago." It did not say that the stars came from the remains of the supernova.
Pluto is still the bastard stepchild in this sad, sad story.
I quote The cluster of thousands of stars dispersed billions of years ago due to a lack of gravitational pull
Well depending on how close the stars realy where, I see the idea of lack of gravity as kind of dumb. If they where far enough apart that there was not enough gravity to hold them together, then how would you even consider these sibblings to begin with. So lets make a assumption here, there was gravitional forces that would atleast cause some affect on these clusters of stars. Wouldent there be some sort of attraction meaning some collisions or obrits of stars. wouldent there more evidance of some sort of orbit of stars as they circled one another over milions of years from the gravity. But them just splitting up dose not sound that right to me.
A finding like this would lend support to the Nemesis theory. If our sun and any of those sister stars are still in some gravitational cycle, it could help explain the periodic extinctions that seem to occur every 26 million years.
A scientist named Twoney is publishing an article in the Astrophysical Journal proposing that a supernova billions of years ago would have resulted in the presence of only one little lonely star in this sector of the galaxy, with the nearest neighbor over four light-years away. "Imagine what a lonely, cold place our solar system would be had this horrible event happened," said Terry Twoney. "Why, our solar system would be so small that life might be viable on just one planet, and Pluto would be so small and cold there would be debates regarding if it even counted as a planet!"
IANAA, but Earth is not my favorite planet. Personally, my favorite planet is Uranus.
Another thing I find odd is the timeline. The universe is around 14 billion years old, and the solar system around 5-6 billion years old. The heavy elements we find in the solar system must have come from supernovas or similar, but type II supernovas take an awful long time to mature, so there can't have been several generations of them; the universe is just too young.
I'm surprised that the Universe is as developed as it is, being this young.
Regards,
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*Art
No, as I understand the theory (and IANAA - well except an occassional amateur one) if a supernova explodes in or near a gas cloud the shockwave initiates star formation.
So a supernova of 20 suns equivalent managed to explode and leave behind thousands of sun-like stars?
No, it managed to leave behind heavy elements. Ya know, iron, uranium, shit like that. The stuff the Earth is made of. We are stardust. We are billion year old carbon.
And, of course (everybody sing):
Oh dear, where can the matter be, when it's converted to energy. . .
Mass and matter are not entirely synonymous and the relevant closed system in this instance is the universe.
KFG
Aren't they Solaris, and Coffee Beans, the N1 Star, and StarSuite, as well as GSun and iSun?
This sig donated to Pater. Long live
Maybe the moon was larger, yet somehow decayed into what it is today.
Have you read my journal today?
Nothing to worry about, it read just like a regular slashdot post. Enjoy your lunch.
"Piter, too, is dead."
Sometimes Sun gets the market share and its siblings vanish into obscurity. Or Sun loses marketshare and DOS or Windows become the star of the show and Sun fades into obscurity. Nothing new. Happens all the time.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
No. The shockwave from the supernova produced localized density increases in a nearby or surrounding gas cloud. These density increases pushed the local gravitational field over the level at which the gas begins to accrete into what will eventually become a star. Such shock waves are the main cause of starts being formed, and the reason why there are "star nurseries" - volumes of space in which a large number of new stars are being born.
Consciousness is an illusion caused by an excess of self consciousness.
Comment removed based on user account deletion
http://en.wikipedia.org/wiki/Pathetic_fallacy
Grabs his hair and runs screaming from the room.
Undetectable Steganography? Yep, there's an app fo
Aye, but where's the supernova remnant itself? The rapidly-rotating neutron star with the nasty high-energy pulsar radiation? It was at the center of the explosion, so it had an initial kinetic energy of nearly zero. It should still be in the stellar neighborhood.
Unless the argument here is that the Sun itself was blown away from the site of the supernova...
type II supernovas take an awful long time to mature
I'm pretty sure that's not true. Remember: the larger the star, the shorter its life. Really large stars have lifetimes of just a few tens of millions of years, while red dwarfs can live trillions, according to current theory. While a 20 solar mass star isn't that big, I imagine it still didn't last long.
Sit, Ubuntu, sit. Good dog.
of a Galactic Porno? I mean, the thing exploded all over the Sun and her Sisters... No wonder they ran away.
Cliff Claven
K.E.G. Party Chairman
Founding Leader of: Koncerned for Egalitarin Governance
I wonder if this would correct that sort of error. Not that I thought about it much it just floated through my mind.
Undetectable Steganography? Yep, there's an app fo
If there used to be more suns in the sky, you'd think it would have been mentioned in the bible. Hmmm . . . ?
This was initially reported by The Posies in 1993:C ldLDjmSWlI&sid=makgy34GX8I
http://www.google.com/musics?lid=AdqZmDxAS1H&aid=
Not to nit pick, he says with a sly smile, but nothing, 'by virtue of not being a thing' cannot move, regardless.
Undetectable Steganography? Yep, there's an app fo
Star stuff indeed.
I'm surprised that the Universe is as developed as it is, being this young.
Er, that sounds a lot like the Anthropomorphic Principal could explain that.
Software sucks. Open Source sucks less.
I'm working on covering this for the Museum of Science, Boston on our podcast. I tracked down a PDF of the actual paper, if anyone is interested.
Why is it that people who can't comprehend second and third order differential equations can still catch a ball? Something even my dog can do.
Undetectable Steganography? Yep, there's an app fo
There I was, expecting some smartassed 'principal' that basically claims 'the moment you anthropomorphise (IE apply human characteristics) the clockwork of the Universe, you're officially wrong' rofl
Weirdest typo I've seen all year.
I hate Grammar Nazi's
Looking for a Rails developer in Chapel Hill?
Dadoo is correct. A very massive star has to have a hotter core at its center in order to support its heavier stellar mass (the hotter the gas, the higher the gas pressure, and hence the more effective to support its own weight in order not to collapse into a singularity, i.e., a blackhole). And the rate of nuclear reaction is often proportional to a higher power of Temperature at the core. That means the hotter the core is, the faster it is to synthesize heavier elements from proton to Helium.
As the same star evolves, it depletes hydrogen (proton) soon at the core. But because the star is still massive, it enables to burn helium, then carbon, oxygen, nitrogen, and eventually it starts burning more heavier elements via nuclear processing (til iron -- Fe -- which cannot be burned to generate nuclear energy).
This heavier element synthesis is accelerated by high temperature and pressure (basically) at the core of a star. For a very massive star (Mass ~ 100 sun) it lives only about a few million years before it begins to show the sign of aging (heavier metallic elements in its atmosphere). And when these stars die, their explosions would disperse these heavier elements throughout its neighboring space (also upon explosion, an ample flux of neutrons would bombard other atoms and eventually the atoms trap the neutrons to form heavier elements than Fe; Strontium, uranium, plutonium and gold are good examples of such process).
In a small star like the Sun, the synthesis process takes place very slowly (in the time scale of a few billion years). So it's only natural that astrophysicits think today that there must have been a lot of very massive stars formed in the early days of the Universe to explain its metallicity level seen today.
FYI, the wikipedia article calls it the "anthropic principle". Would "Anthopomorphic principals" be like when they have a pet wedding with dogs wearing dresses and tuxedos?
Prov 9:8 Do not rebuke mockers or they will hate you; rebuke the wise and they will love you.
At any rate, it's best not to take notice, as the world seems to be on max pedophile alert.
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
Funny thing is, I know the difference, and didn't notice, because Wikipedia pulled up the right article, even with the typo, and the fact that it's more commonly known as the Anthropic Principle. (I also know what a run-on sentence is, apparently.)
Software sucks. Open Source sucks less.
That's "Interstellar Incest", you Insensitive Clod!
My other body is also not wearing any.
No kidding? That's amazing. I would never have imagined that. So the explosion involves some kind of jetting effect that sends the remnant off with a high velocity? That's wild.
I'd like to make the point that this scenario is what we expected from observing other stars and clusters.
Stars start forming when giant molecular clouds are compressed, typically by the mass density wave of a spiral arm. This creates a star-forming region, where many thousands of stars will be formed in close proximity. Because the gas is able to efficiently shed kinetic energy (transforming it into heat), the stars have low velocities relative to each other, so are gravitationally bound in an "open cluster". (The Pleiades cluster is a spectacular nearby example.)
Stars of many sizes (masses) are formed, and the high mass ones very quickly run through their lives and explode as supernovae, while the stars are still in a cluster. (The lifetime of a star has roughly an inverse-cube relationship to its mass.)
Over a period of tens of millions to billions of years, the cluster is broken up. (How long it takes depends on its location in the galaxy and how tightly bound it was initially.) I think that tidal effects from passing molecular clouds and spiral arm waves are mostly responsible for this, but it is long enough since I've studied this that I could be mistaken. By now, the sun's sisters are probably distributed uniformly in a ring around the centre of the galaxy. The supernova remnants are long, long gone.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
thankyou, thankyou, I'll be here all week
Patriotism is a virtue of the vicious
Thanks for the pointer.
A couple of more serious questions:
Surely if a supernova was that close it would be the event that started the formation of the sun, rather than happening after its formation.
What's the effect of the outgassing (explosion) on the proper motion of the created stars? What percentage escape the gravitational field of the embedded neutron star?
Squirrel!
So a supernova of 20 suns equivalent managed to explode and leave behind thousands of sun-like stars? Apparently conservation of mass laws were different back then.
conservation of mass is not the issue. The sun-like stars were not made from the mass of the exploded star. The explosion caused a shock wave in the interstaller gas. The shock wave is a density variation that trigged gravatational colapse at hundrds of points in the cloud. Some of those points became stars.
shouldn't he be studying moons instead of stars?
I am know expert but aren't all the element cook up in stars and then disperse by either solar wind or supernovae. We have a pretty good selection of elements here on earth. So much much so that we were able to identify 92 natural elements. 36 of which can only be formed in the explosion of a supernova. Isn't likely that those elements were formed in nearby stars with a close proximity to our sun given the fact that inverse square relationship to particles dispersion and our solar system has rocky planets. Since we apparently have a good supply uranium, our sun would have be near a supernova early in life. This doesn't seem like news because the lone nebula theory would seem unlikely because it would have accounting for all the heavy element material that made up the planets. All I really wonder is there a black hole nearby in our galactic neighborhood?
You don't have to be smart to use a Mac, you just have to be smart enough to buy one
"So a supernova of 20 suns equivalent managed to explode and leave behind thousands of sun-like stars? Apparently conservation of mass laws were different back then."
Apparently you had trouble comprehending TFA, assuming you read it in the first place.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
I'm confused. Were this SparcStations?
MjM
XKCD:Xeric Knowledge Comically Dispen
-The shock wave from the supernova (which is rich
in heavy elements) will sweep up interstellar gas
until the total supernova remnant will be a shell
of hundreds -or even thousands- of solar masses
of gas, sometimes with a neutron star or a black
hole in the center remaining of the star.
If one part of the supernova remnant has swept up
enough gas, the compressed gas can begin to contract
under its own gravity
to create the next generation of stars.
Typically, when a big nebula begins to collapse,
the heaviest fragments contract first, creating
short-lived giant stars that explode and seed the
rest of nearby space with heavy elements.
The shock waves then fragment and contract into new
proto-stars, with sizes distributed from many very
small red dwarf stars to a few bigger stars.
Yours Birger Johansson, Sweden