Skip to comments.Supernova debris found on Earth
Posted on 11/24/2004 1:22:08 PM PST by Phsstpok
Published online: 02 November 2004; | doi:10.1038/news041101-5
Supernova debris found on Earth
Ancient explosion may have affected climate and, possibly, human evolution.
Cosmic fallout from an exploding star dusted the Earth about 2.8 million years ago, and may have triggered a change in climate that affected the course of human evolution. The evidence comes from an unusual form of iron that was blasted through space by a supernova before eventually settling into the rocky crust beneath the Pacific Ocean.
Gunther Korschinek, a physicist from the Technical University of Munich in Germany, leads a team who in 1999 found the first deposits of supernova matter on Earth1. But it was impossible to date the supernova accurately from those samples, because the material was distributed through several different layers of rock.
The team has now analysed a different piece of ocean crust, where the supernova detritus is concentrated into a clear band of rock that can be accurately dated. The researchers found small but significant amounts of an isotope called iron-60 in the rock, which could only have come from a supernova.
"We've looked at all the possibilities and we can't find anything else that could produce such quantities," Korschinek says. The researchers report their results in the latest issue of Physical Review Letters2.
"It represents an experimental triumph and a milestone in this field," says Brian Fields, an astrophysicist from University of Illinois at Urbana-Champaign. He argues that the result marks the birth of a completely new area of research, which he calls "supernova archaeology"3.
Comets and meteorites also deliver matter to Earth, but they always come from within our Solar System. Supernovae are the only known source of interstellar debris. "The very fact that a supernova can dump material on the Earth is, to my mind, rather spectacular. It demonstrates that the Earth is not independent of its cosmic environment," says Fields.
When the iron-60 arrived from space, it was evenly distributed all over the Earth. But the signatures are only detectable in crust that has lain undisturbed for millions of years, such as certain parts of the Pacific Ocean floor. This particular crust was taken from an area a few hundred kilometres southeast of the Hawaiian Islands in 1980. It was collected by oceanographers who were investigating the rocks as a potential source of rare mineral ores.
Korschinek estimates that the supernova was between about 100 and 200 light years away and happened 2.8 million years ago, give or take 300,000 years. The explosion can't have been too close to Earth, or it would have delivered enough radiation to cause mass extinctions. Conversely, if the supernova was any further away, more of the iron-60 would have been filtered out by the thin wisps of matter drifting between the stars.
This means the supernova would have been at the right distance to spray out a stream of cosmic rays that could have increased the cloud cover on Earth. Korschinek calculates that there may have been 15% more cosmic rays arriving on Earth than normal for at least 100,000 years. This is not enough to actually kill anything, but was perhaps sufficient to change the Earth's climate.
The increase in cloudiness would have cooled the surface, tying up water as ice at the poles and leading to a dryer climate in Africa. Climate records in rock cores match the dates of the supernova event.
"Some people believe this climate change in Africa was a driving force in our own evolution," adds Korschinek. The argument is that a drier climate in the continent would have forced humans to adapt4, and to spread out to other, wetter areas.
The team is now looking for other unusual isotopes in the crust sample, which may reveal more about the type of star that caused the supernova. But there are probably 10,000 times fewer of these atoms than of the iron-60, says Korschinek, so they will be extremely difficult to measure. "We're sweating, and I don't know if we will succeed," he says.
"It demonstrates that the Earth is not independent of its cosmic environment"
This article caught my attention because of the title. I've always been under the impression that all of the complex atoms that are the basic building blocks for, well, just about everything, including us, was formed in stellar explosions, either novas or super novas. In that case the title is pretty dumb as everything we've ever encountered is basically supernova debris.
On reading the article I thought a bit more about things like global warming. How many billion other variables haven't these clowns taken into account?
Then I was reminded of this thread:
After a Trio of Explosions Scientists say Supernova is Imminent
I think the moral of these articles is duck and cover!
BS is my first reply. Someone is looking for a grant.
"Ancient explosion may have affected climate..."
No way! Only humans (especially SUV owners") can affect the earths climate.
I'm too ignorant for this thread. But I did read that what we call "Cosmic Rays" are in fact "heavy iron nuclei" iron isotopes stripped of their electron shells, I gather. Traveling at near light-speed, these are by far the most damaging, penetrative form of deep-space radiation and the biggest complication of interplanetary human travel.
I didn't know Michael Moore was that old!........
Undoubtedly more stuff the klintons stole when they left the Whitehouse.
2.5 million years is an eyeblink in cosmic terms.
An "At least one luddite has found this thread so far" ping.
Catastrophism for atheists ping.
"Supernova debris found on Earth"
Could someone let me know when it gets to eBay?
Actually, predicting the past is no trick.
Accurately interpreting it, however, is another matter.
always my first assumption about "science" in the news. However, just because a scientist is pimping for federal money, it doesn't mean they are 100% off the mark. Merely suspect and worthy of close scrutiny.
Check the data! Always check the data!
Well, since I reference the fact that basically everything (except Hydrogen and Helium) is only possible as the result of a nova or supernova.... it's already on e-bay.
In fact, everything on e-bay is a supernova remnant, if you think about it in the right way....
Yes, right here and all over the Web, too:
Actually, many elements are formed in stars long before they go nova or supernova. Once hydrogen fuel is depleted, stars start fusing helium into carbon and oxygen, then those elements are subsequently fused into even heavier elements such as nitrogen and silicon, finally culminating in iron. All elements heavier than iron are formed in supernova explosions. The fact that Earth is rich in those heavy elements is proof that the primordial dust cloud of our solar system was enriched by supernova explosions, which also probably started the initial gravitational collapse of the dust cloud.
Yeah, These are the same guys that interpret the constitution to BAN GOD from the public discourse!
I have always been under impression that EARTH itself was Supernova Debris.
You know, creationists have been claiming the death of evolution for more than a century now. I guess y'all assume you might be right one day.
Tens of thousands of biologists are not holding their breaths, however.
"Impossible! The earth is only 3,000 years old.< /creationism >"
Creationism is a much wider field and encompasses far more views and theories than that. Earth being changed to become more receptive to human life as a result of super nova matter distribution could fall into both progressive and theistic views of Creationism.
The Imminent Demise of Evolution. (The endless crisis.)
It wasn't really a Supernova it was 69' Nova SS with a 454. At 5500 rpm a rod went through the side of the block, allowing some pieces of cast iron, Valvoline 20-50w and Prestone Anti-freeze to be expelled into the atmospere and along the side of the road. Also causing a noticable decrease in forward velocity. But no scientific facts of change in human evolution, except maybe on not using old connecting rods in a high h.p. engine.
..predicting the past is no trick.
Just need to know the bias of who's doing the 'predicting' of what has already happened.
The curve of binding energy. :-)
Sorry if I misrepresented the creationist viewpoint.
I was trying to be funny. (Dang, failed again!)
Anyway, I believe the Bible. God did it!
Supergiant stars have short life in cosmic terms, like 100 million years. Smaller the star, the longer itn will live because it is burning less fuel. It is likely that billions of years ago, there were supernovas not too far from our Solar System. When supergian stars exploded, they produce heavy elements like iron to uranium. When stars have iron appearing, it is sign it will start to die and go supernova. If a supernova happened near us, we would be bombarded with deadly gamma and cosmic rays. It would kill almost all life on this planet.
Not exactly true, (other than the man-made elements) there are fusions that create elements
just above iron, but obviously a pittance compared to iron.
I agree. It is impossible to date anything with any type of isotope unless you have something that you can prove was made at the date you are looking at. A million years, a billion years or 50 years... it does not make any difference unless you already have a sample that was also made at that time. This is all intellectual BS.
I think ancient SUV debris was also found in the rock layers.
The fusion of iron consumes more energy than it releases, so it doesn't occur except in the case of supernova explosions, with their enormous neutron flux bombarding iron atoms to form heavier elements.
I've heard that heavier elements can form in the accretion disks of black holes, but that's the exception that proves the rule.
What where you referring to?
Beef eating SUV owners.
It is Bush's fault!
There was a rock...the monkey got cold...and it evolved because it needed to build a fire. Well Halleluiah! They proved the theory. No more debate necessary.
Not true. Looking at the daughter product ratios gives the initial date and isotope composition.
This may be a really stupid question, but why are various elements contained in deposits and veins? I don't see any reason why iron, uranium, gold and other mineral atoms would gravitate toward each other. I would think that elements would be fairly evenly mixed.
For sure, God did it. Those of us who study physics, chemistry, etc., are simply teasing out the rules of the mechanism He set up to do so.
I'm not a geologist, but I think heavy metals tend to gravitate towards each other in the semi-liquid mantle of the planet because they have similar densities, and so tend to move around in the slow convection currents of the mantle in similar ways.
In short, what you see now reflects not the primordial dust cloud that the Earth formed from, but an Earth molded by billions of years of geological activity.
Not without a confrimation ...such as a hammer with an inscription that tells us that this hammer was made in Nashville, Tennessee by the Thor Iron Works on 2 August 1914 AND you've got the ironworker that made that particular hammer testifying on oath that he indeed made that particular hammer on that date.
If a rock is a billion years old... you've got to have another sample of rock that you can prove to be a billion years old. Otherwise... there is not a word of truth in it.
You make a good point. Catastrophism on the moon, on Mars, on Jupiter and now a supernova. But catastrophism on earth? Can't be, because it would disturb uniformitarian sleep.
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