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Supernova May Explain How Planets are Formed
ExE122 writes "A young pulsar that formed from a supernova which happened about 100,000 years ago and is sitting 13,000 light years away may solve some questions about the origins of Earth. From the article: 'Scientists think they have solved the mystery of how planets form around a star born in a violent supernova explosion, saying they have detected for the first time a swirling disk of debris from which planets can rise. The discovery is surprising because the dusty disk orbiting the pulsar, or dead star, resembles the cloud of gas and dust from which Earth emerged. Scientists say the latest finding should shed light on how planetary systems form.'"
Form the article:
Chakrabarty said the debris disk most likely formed from metal-rich material that failed to escape the supernova. The disk resembled that seen around sun-like stars, leading researchers to conclude it might spawn a new planetary system.
Radiometric dating points to the earth's inception being ~4.6 billion years ago. I want to know if the U238 that exists today was created as a result of the supernova that blew apart the solar system that provided all the matter for this one. All the U238 that we've found in this solar system so far points to our entire system being ~4.6 billion years. If the U238 was in fact created by this supernova, then we can't say that the earth as a planet is ~4.6 billion years old.
I really hope no creationists read this, I don't mean to give them any fodder.
Does this sig remind you of Agatha Christie?
Hopefully this will put to rest the "static cling" model of planet formation once and for all!
The difference between stupidity and genius is that genius has its limits.
This new data conclusively proves that the Earth was, in fact, created last Tuesday. Researchers are still double checking the math, though.
A note about the article is that any planets that might be formed from the cloud of debris would be orbiting a pulsar Even if it has planets, it doesn't tell us much about how our own solar system could have developed.
You are reading a copy of my copyrighted post.
How can suprnova explain anything after it was shutdown?
.torrent-ed into p2planetary systems like the young mininova we dwell in.
:)
Simple! After suprnova exploded out of existence in a cataclismic B-RIAA-kdown, its remains were
See?
How could that parent post be "offtopic"??
It's a legitimate question that can be asked, though I think that the radiometric measurement takes the thought into account already (admittedly I don't remember the detail of such measurement).
"Supernova May Explain How Planets are Formed"
Huh? And here I thought it was when a mommy planet and a daddy planet got together. Although how they get anything done with all those astronomers looking on is a complete mystery.
Have scientists actually seen the cloud of gas and dust from which Earth emerged 4.6 billion years ago, or is this just wild speculation?
Ever heard of Zodiacal light?
Any cloud of gas would have been blown out of the system at the early stage of the Sun's evolution (T-Tauri phase), but some dust remains in the solar system. We see that today, too.
Stars fuse H into He and so forth all the way up to lead (Pb). Lead is a problem because it inhibits further reactions. Any elements past lead come from when the star explodes.
It tells us that planet-formation disks can live in surprising places. That probably sets some useful limits on the range of hypotheses that work for planet formation.
Has nothing to do with the earth's age. The article is only talking about the formation of planets around a supernova - and that is not what happend in our solar system.
The article says that any planets which form are likely to be uninhabitable because they're, to put it bluntly, made out of reactor waste.
Why couldn't you have radiation-tolerant species?
If they went on to have multicellular descendants, then intelligent ones, those descendants could build cheap nuclear spacecraft including Orion-class vehicles and operate them without fear of radiation poisoning.
What?
The explosion in the article happened 13,000 light years away. That's a measure of distance. This has nothing, repeat nothing, to do with our solar system. Our solar system was formed as the result of a supernova *more* than 5 Billion years ago. The U238 on our planet is the remnant from *that* supernova, not from one that happened 100,000 years ago.
Sheesh.
On the other hand, if your rather confused grammar is trying to say that the precursor star to the sun (or many precursor stars as supernovas often occur in groups -- being formed from groups of super-giant blue-white stars [see Pleides]) created all the U238 4.6BYA and that the Earth must therefore be less than 4.6BY old. If that's the case, then yeah, maybe the Earth itself is less than 4.6BY old. So what? It just means that the rock it formed from took a little while to condense into its current shape. It's not like the Earth formed, oceans, mountains, and all on Tuesday the 13th of July, 4,600,000,000 BC. It takes tens of millions of years for the matter to acrete into a planet.
If you're wondering in general did all the U238 come from a supernova, then the answer is simple. Yes. So did every element heavier than iron on the periodic table. A supernova is the only place those elements can be formed in nature (at least in any quantity.)
Iron is the energy dead end. When a star runs out of hydrogen, it starts "burning" Helium, when it's out of Helium it starts "burning" boron, and carbon, and oxygen into heavier elements. But when it hits iron, that's the end of the road. There's simply no more energy to get out by fission or fusion. The star is effectively dead. The trick is, if a star can actually reach the silicon "burning" stage where iron is the byproduct, then it's so massive, it's going to go supernova anyway. Part of the energy of the supernova goes into fusing Iron and other leftover bits to produce elements higher on the periodic table. This *costs* energy, so the only place it can happen is a supernova. Thus every element higher than iron (Silver, gold, platinum, lead, mercury, uranium, praseodimium, lanthanum, radium, etc.) had to be formed in a supernova.
Welcome to the universe. You are made of exploded stars. If there had been no Phase I (metal-poor) stars, there would be no planets, no humans, no nothing, because everything else is made of their exploded corpses.
Life, the Universe, and Everything... in my image.
You seem a mite bit confused. The article isn't saying that the Earth was created by the mentioned supernova. It saying that this discovery might help us figure out how planets come into being; of which the Earth is one.
That 100,000 year figure has nothing to do with the 4.6 billion year estimate - two different supernovas.
And... Yes, the extant U238 was most likely created by the supernova that created our solar system.
The whole accretion-disk-clumping-into-planets theory has been around for decades, and we've seen signs of accretion discs around stars before. What's new here is that such a disc has been found around the remnants of a star that's already gone supernova -- an event which would have destroyed any previous solar system.
This is the missing link which explains why we've found planets around pulsars, because any planets formed earlier in the star's lifetime would have been destroyed in the supernova.
Shortly after forming a number of planets, the Suprnova was shut down by pressure from NPAA (New Planet Association of the Americas). However, other services such as mininova have conveniently filled the niche. A spokesman for NPAA claimed that they would continue their ruthless domination until no new planets could be formed.
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Radiometric dating points to the earth's inception being ~4.6 billion years ago.
Radiometric dating.. I guess that's the first stage in how planets make other planets.
Latewire
Funny maybe - but certainly not interesting.
TFA talks about the observed disk providing evidence that planetary disks are more stable than previously thought - NOT that the supernova involved in the creation of THAT specific disk also created our solar system.
FTFA:
Good point! Though you were a complete jerk about!!!
They will ley us know for sure in a million years or so.
Don't be such an asshole! Intelligence doesn't make good people no sir!
sheesh!!!
Radiometric dating points to the earth's inception being ~4.6 billion years ago. I want to know if the U238 that exists today was created as a result of the supernova that blew apart the solar system that provided all the matter for this one.
The U238 was definitely formed in a supernova. Basically all heavy elements were.
It should be noted, however, that this implies that the solar system is at least 4.5 billion years old. It can't be less.
This is what's stated by radiometric dating, anyway. They can only date to when the radioactive material was deposited.
Looks like you're right. Thanks!
Actually the world is going to be created next Tuesday. We're just the false memories of someone from the future remembering the imaginary past that God created to test their faith.
"The White House is not an intelligence-gathering agency," -- Scott McClellan, Whitehouse spokesman.
Yes, how outrageous of him to suggest that when posters make a claim, they try to do it in a way that actually makes sense.
Welcome to the universe. You are made of exploded stars.
This begs the question; which elements heavier than iron (#26) are essential components of the human body?
According to Wikipedia, we contain trace amounts of cobalt(27, part of vitamin B12), copper(29), zinc(30), selenium(34), bromine(35), strontium(38), molybdenum(42), iodine(53), and lead(82). All of these (except strontium, it seems) can cause medical problems if absent. (yes, even lead!)
You also may contain traces of arsenic(33, if you play with ant poison), mercury(80, if you eat too much tuna), and gold(79, if you drink too much Goldschlager). Some multivitamins also contain nickel(28) and tin(50). Certain quack "nutritional" supplements contain silver(47), gold(79), platinum(78), germanium(32), indium(49), and who knows what else... Be sure to cook your supernova thoroughly before eating!
Weeks of coding saves hours of planning.
A Debris Disk Around An Isolated Young Neutron Star
Credo sim. - I think I am.
Not every element greater than Fe was created in a supernova explosion. Much might of been created by the collision of Neutron Stars.
An Education is the Font of All Liberty
At 11 tonight, we're all going to break out of our jars and make a run for it. Pass it onto the next brain.
It's not offtopic, dumbass. It's orthogonal.
My your feeling important. :>)
We're just parterns of iron oxide created in some rock (sometime around 3000 AD) that will eventually be dug up by an alien archologist (sometime around 4000 AD) to test his faith that the dulaxians are the chosen people (and single intelligent creation) of the great Azog.
Kind of a pitty that the bits will be too scrambled for him to read this.
This is not entirely accurate. A star begins converting helium into beryllium when the pressure due to hydrogen fusion is no longer able to support the gravitational induced collapse of the star. It's all about balancing forces.
It is believed that often this will happen when hydrogen fusion is still taking place towards the surface of the star. In the end, it is quite likely that a large star will resemble an onion, with several layers where different nuclear reactions are taking place. So He -> Be can happen while H -> He is still happening in a star.
887321 = 337*2633
I could of sworn I corrected some of those.
s/parterns/patterns/
s/archologist/archeologist/
s/Azog/Arzog/
..so feel free to mod me offtopic, but I submitted this same story with NASA as the news source and it was rejected. Perhaps my title was less interesting.
m ight-form-around-super-novaed-stars/
http://www.abandonedstuff.com/2006/04/05/planets-
Oh You POS
I gues it all depends on what your definition of "old" is. Different things can have different ages. The uranium was formed in a supernova explosion, but I doubt that a single supernova provided all of the heavy elements that make up the earth. Much more likely, way back in the "good old days" when what would become the solar system was just a tiny part of a vast cloud of gas on the outskirts of the galaxy, many supernova were happening in stellar nurseries, each of which ejected heavy elements which contributed to the chemical composition of the cloud. Eventually one or more of these explosions also triggered the gravitational collapse of the cloud (or this part of it) which formed the sun and our neighbors. So some of the uranium would be about 5 billion years old (b.y.o), some might be six, and some seven or more. Same thing for the other elements as well. Of course, the hydrogen atoms that make up the water in our oceans are thirteen billion years old. The helium could be anywhere from thirteen to five b.y.o. So how old is the earth as a planet? That's easy. 4.5 b.y.o. Asking "as a planet" refers to the organization of the constituents, not the age of the material itself.
There's tons of fascinating material about the development of solar systems and planets available. Even the older stuff is interesting, and is generally still roughly correct. Granted, we're learning much more nowadays with more refined detail, and the models we have can be tested against better observations that weren't possible to make a few decades ago. It's a story well worth looking into.
In theory, there's no difference between theory and practice. In practice, there is.
This begs the question
No, it doesn't.
Yes and no, mostly no. The initial material is pretty radioactive, but that doesn't last long. Most of the radioactive isotopes have very short half-lives. Half-lives in the millions of years is rare.
This means that a planet formed from the debris of a star that went supernova 100 million years earlier will not be that much more radioactive than Earth.
So for all practical purposes, no. The radioactivity dies out around the same time as planet formation.
Professional Wild-Eyed Visionary
s/of/have/ s/your/you're/ :-)
"The White House is not an intelligence-gathering agency," -- Scott McClellan, Whitehouse spokesman.
To be accurate, no fusion ever occurs "near the surface of the star". Current estimates are that when our own sun burns out in about 5 Billion years, it will have burned only about 10% of the available hydrogen in the star. Were we to have some method to "stir" the Sun, then we could keep it merrily burning along for several billion more years.
However, yes, there are more than the few steps I listed in the reactions that go towards a supernova. And several of them probably take place at the same time. As the hydrogen in the core begins to thin out, mixed with its helium waste, the force of the fusion will decrease and gravity will press down on the mix. When this happens, the outer shell often starts to drift outward, as the photonic pressure on the surface balances it against the gravity. Then as the core squeezes down, the photosphere remains balanced by the outgoing energy (which takes upwards of a million years to make the trip from core to surface) and since the rest of the star falls inward, the photosphere gets pushed out and you get the start of a planetary nebula.
Then when the pressure and heat in the core get high enough, the next stage begins. Hydrogen, mixed with Helium will fuse to lithium, helium fused to helium will give you beryllium...
Each stage will have a brief period of balance, as a rule, lasting about half as long as the previous stage, so if it took a billion years to run out of hydrogen, then the "helium burning" stage will take about half a billion years, and so on.
Each stage also precipitates another outward and inward push. Each stage makes a new "puff" of the outer shells into the rather stunning view that is a planetary nebula.
But when the star runs out of anything but iron in the core, there's probably still about 70% of the star's mass remaining that's still 90%+ hydrogen. It's not like the whole star is turning into a big iron ball.
Once you reach iron, the compression begins, and since there's no fusion beyond that point, you begin to squeeze the electron shells until they have no room to move, but instead slam into the nucleus of the atoms. When they do this, the protons and electrons fuse into neutrons (emitting neutrinos in the process). This final collapse has been estimated to take seconds, or possibly fractions of a second.
This will fuse anything left that isn't iron in the core, the collapse to neutrons is also hugely energetic. (I'm not sure where the other poster got the idea that everything suddenly changes back to helium. That would violate lots of physical laws, entropy among them.) The inner layers (up against the core) are hit with a stunning shock wave, and they begin to fuse, adding to the energy of the shock wave. The fusion rips through this inner area converting lower elements to higher ones because the shock wave is so powerful. Rapidly this energy is absorbed by electron shells further up, and are re-emitted as nasty, nasty high-energy x-rays and gamma rays. These will be so powerful that when they overtake the rings of expelled matter, they will super-heat them and you'll get glowing rings of gas lit by the wave of energy.
It's this massive wave of energy as the core collapses into a neutron star that *is* a supernova. What's left is an Earth sized ball of pure neutrons, spinning hundreds, perhaps thousands of times a second. From our observations of SN1987A (the supernova of 20-S Doradus) we know that the neutron star spinning madly is basically a pulsar, shedding x-rays as matter falls to its surface, pushing clouds of gas away under a stellar wind that dwarfs our Sun's paltry flow.
In fact, SN1987A is so massive that it should have collapsed to a black hole, but for the moment, it's spinning *so* rapidly that it cannot collapse all the way down, centrifical force holding it at the brink of collapse.
For now it's pushing the mass it expelled away from itself, where it will give birth to new stars and planets. Later, it will collapse into a black hole, somewhat dampening the party potential for any sentient life-forms in the area.
Life, the Universe, and Everything... in my image.
Thanks, I've been working on it. Of course, at least I put my name on my responses.
I don't feel a lot of need to be polite to ignorance, and I've often found that a good wake-up call is best delivered with a figurative slap-in-the-face.
Life, the Universe, and Everything... in my image.
Political correctness and stupidity "don't make good people" either. If you feel the need to call me out, at least do it with a real name, don't hide behind the AC tag.
Life, the Universe, and Everything... in my image.
Sorry, my own bug. The size of a neutron star is measured in tens or hundreds of miles. Not the size of the Earth. I had a white-dwarf moment there and mixed up scales.
Life, the Universe, and Everything... in my image.