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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."
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.
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?
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?
Allow me to introduce my good friend, Kinetic Energy.
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.
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,
--
*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.
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
Grabs his hair and runs screaming from the room.
Undetectable Steganography? Yep, there's an app fo
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.
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.
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.