Nasa's Glorious Failure

[Siggie]

Re: Nasa's Glorious Failure

Yeah, but it's just grasping at straws.

Grasping at straws?! All they've collected is consistent with the theory, but naw it's all grasping at straws.
If it's all grasping at straw there should be plausible alternative explanations for all the evidence they found that can't be ruled out.
Alright then, you explain the massive amount of iridium at K-T boundary.

[KanadaHye]

Re: Nasa's Glorious Failure

Alright then, you explain the massive amount of iridium at K-T boundary.

I already did.... volcanic eruptions.

here is some info to backup my theory... remember that the Earth's core is metallic in nature.

http://en.wikipedia.org/wiki/Piton_de_la_Fournaise
"Some of the beaches there are of a greenish colour, because of the olivine sand resulting from picrite basalt lavas. The Grand Brűlé is formed from solidified lava flows accumulated over hundreds of thousands of years; the most recent ones are often the darkest and most vegetation-free, while older ones can be covered by dense wild vegetation. Iridium is being ejected through these vents."

[Siggie]

Re: Nasa's Glorious Failure

I already did.... volcanic eruptions.

here is some info to backup my theory... remember that the Earth's core is metallic in nature.

http://en.wikipedia.org/wiki/Piton_de_la_Fournaise
"Some of the beaches there are of a greenish colour, because of the olivine sand resulting from picrite basalt lavas. The Grand Brűlé is formed from solidified lava flows accumulated over hundreds of thousands of years; the most recent ones are often the darkest and most vegetation-free, while older ones can be covered by dense wild vegetation. Iridium is being ejected through these vents."

No, not whether there's iridium on Earth... Is there iridium in the quantity observed?

[KanadaHye]

Re: Nasa's Glorious Failure

No, not whether there's iridium on Earth... Is there iridium in the quantity observed?

"Iridium is rare in the Earth's crust, but it is found at higher concentrations in some volcanic flows, suggesting that the Earth's core is richer in this element. Also, iridium is relatively common in meteorites.

The element is found in nature with platinum and other platinum group metals in alluvial deposits. Naturally occurring iridium alloys include osmiridium and iridiosmium, both of which are mixtures of iridium and osmium. Iridium is recovered commercially as a byproduct from nickel mining and processing."

http://www.newworldencyclopedia.org/entry/Iridium

"Sublimates and incrustations derived upon the cooling of volcanic gases have been collected on various sites (Piton de la Fournaise, Poas, Momotombo, Etna, Ardoukoba and Erta‐Ale). They have been analysed for Ir and other volatile elements (Se, As, Cu, Au, Ag, Pb, Tl) by means of instrumental neutron activation analysis (INAA) and proton induced X‐Ray emission (PIXE). Among the investigated volcanoes, only Piton de la Fournaise is found to release detectable amounts of iridium. Ir in Piton de la Fournaise sublimates is associated with F‐minerals. This confirms its gaseous transport as a volatile fluoride compound.

Iridium seems to be preferentialy released by hot‐spot type volcanoes, and its detection in Piton de la Fournaise sublimates provides a positive argument in favour of a volcanic hypothesis to explain the KTB events."

http://www.agu.org/pubs/crossref/198...12p01391.shtml

See... I'm not the only one that thinks like me.

[Siggie]

Re: Nasa's Glorious Failure

"Iridium is rare in the Earth's crust, but it is found at higher concentrations in some volcanic flows, suggesting that the Earth's core is richer in this element. Also, iridium is relatively common in meteorites.

The element is found in nature with platinum and other platinum group metals in alluvial deposits. Naturally occurring iridium alloys include osmiridium and iridiosmium, both of which are mixtures of iridium and osmium. Iridium is recovered commercially as a byproduct from nickel mining and processing."

http://www.newworldencyclopedia.org/entry/Iridium

"Sublimates and incrustations derived upon the cooling of volcanic gases have been collected on various sites (Piton de la Fournaise, Poas, Momotombo, Etna, Ardoukoba and Erta‐Ale). They have been analysed for Ir and other volatile elements (Se, As, Cu, Au, Ag, Pb, Tl) by means of instrumental neutron activation analysis (INAA) and proton induced X‐Ray emission (PIXE). Among the investigated volcanoes, only Piton de la Fournaise is found to release detectable amounts of iridium. Ir in Piton de la Fournaise sublimates is associated with F‐minerals. This confirms its gaseous transport as a volatile fluoride compound.

Iridium seems to be preferentialy released by hot‐spot type volcanoes, and its detection in Piton de la Fournaise sublimates provides a positive argument in favour of a volcanic hypothesis to explain the KTB events."

http://www.agu.org/pubs/crossref/198...12p01391.shtml

See... I'm not the only one that thinks like me.

http://www.psi.edu/projects/ktimpact/ktimpact.html

The evidence as a whole, for this particular event points to impact. As noted in the summary linked above, there have been other extinctions for while scientists have not attributed to impacts because the evidence isn't there.

[KanadaHye]

Re: Nasa's Glorious Failure

http://www.psi.edu/projects/ktimpact/ktimpact.html

The evidence as a whole, for this particular event points to impact. As noted in the summary linked above, there have been other extinctions for while scientists have not attributed to impacts because the evidence isn't there.

Entirely different time period... but....

Researchers debunk ancient comet-strike theory

CARBONDALE, Ill -- They say diamonds are forever. But in this case, they were never there to begin with.

A team of researchers led by a geology professor from Southern Illinois University Carbondale recently punched a hole in a well-known theory involving an ancient alleged comet or meteor strike wiping out a great deal of life on Earth and changing its climate. The “Younger-Dryas Impact Hypothesis” relied on various geological evidence, most of which other scientist have found lacking in recent years. The final bit of evidence left standing was the alleged existence of tiny “nanodiamonds” supposedly created by the intense force of the impact, which the theory holds happened about 12,900 years ago.

But the team, including SIUC geology Professor Nicholas Pinter, the primary investigator on a three-year National Science Foundation-funded study, recently released findings that directly contradict the theory. The researchers found that what supporters of the hypothesis identified as nanodiamonds aren’t actually diamonds at all, but simple carbon that is related to the very common substance graphite.

“The science is now clear that this supposed impact was a non-extent event,” said Pinter, who began working on the project in 2008 and collected samples in California and Arizona as part of it. “You can’t have an event like this that would supposedly affect all of North America and South America” and not have it leave evidence in the geologic record.

The Younger-Dryas Impact Hypothesis aimed to explain a time period following the last ice age, when ongoing warming suddenly stopped and the climate returned to a glacial period. This approximately 1,300-year period, known as Younger Dryas, saw North America experience massive extinctions, including many larger species such as mammoths, mastodons, saber-tooth tigers and others. Humans also were greatly impacted, with tools such as Clovis stone spear tips disappearing.

The hypothesis, which gained popularity a few years ago, holds that a comet or meteor impact was responsible for the climate’s abrupt turnaround and the subsequent effect on life forms. But the evidence for such an event has been under scrutiny the last few years, with much of it discredited, Pinter said. The final evidence its supporters pointed to were carbon spherules that contained nanodiamonds such as Ionsdaleite, a rarely observed hexagonal-shaped diamond formed by the impact.

Pinter’s team, which includes researchers from Washington University in St. Louis and Royal Holloway University of London, used transmission electron microscopy to examine samples from the western United States in search of the objects. Their research identified the objects as graphene and graphene/graphane oxide. They also demonstrated that previous research mislabeled those substances as hexagonal diamonds and cubic diamonds.

Pinter said with the final supporting evidence of the theory now impeached, scientists can return their attention to what really did happen during that time period, and how that resulted in so much change.

“This affected what is now Southern Illinois, too,” Pinter said. “There were mammoths and mastodons and possibly saber tooths roaming this area 15, 000 years ago. The vegetation was completely different, more a spruce-dominated land. But now we can get back to asking important questions about when and why this changed.”

The journal “Proceedings of the National Academy of Sciences” is publishing the findings under the title, “No evidence of nanodiamonds in Younger-Dryas sediments to support an impact event.”

http://news.siuc.edu/news/September1...0tjc10070.html

[Siggie]

Re: Nasa's Glorious Failure

Researchers debunk ancient comet-strike theory

Entirely different time period... but....

CARBONDALE, Ill -- They say diamonds are forever. But in this case, they were never there to begin with.

A team of researchers led by a geology professor from Southern Illinois University Carbondale recently punched a hole in a well-known theory involving an ancient alleged comet or meteor strike wiping out a great deal of life on Earth and changing its climate. The “Younger-Dryas Impact Hypothesis” relied on various geological evidence, most of which other scientist have found lacking in recent years. The final bit of evidence left standing was the alleged existence of tiny “nanodiamonds” supposedly created by the intense force of the impact, which the theory holds happened about 12,900 years ago.

But the team, including SIUC geology Professor Nicholas Pinter, the primary investigator on a three-year National Science Foundation-funded study, recently released findings that directly contradict the theory. The researchers found that what supporters of the hypothesis identified as nanodiamonds aren’t actually diamonds at all, but simple carbon that is related to the very common substance graphite.

“The science is now clear that this supposed impact was a non-extent event,” said Pinter, who began working on the project in 2008 and collected samples in California and Arizona as part of it. “You can’t have an event like this that would supposedly affect all of North America and South America” and not have it leave evidence in the geologic record.

The Younger-Dryas Impact Hypothesis aimed to explain a time period following the last ice age, when ongoing warming suddenly stopped and the climate returned to a glacial period. This approximately 1,300-year period, known as Younger Dryas, saw North America experience massive extinctions, including many larger species such as mammoths, mastodons, saber-tooth tigers and others. Humans also were greatly impacted, with tools such as Clovis stone spear tips disappearing.

The hypothesis, which gained popularity a few years ago, holds that a comet or meteor impact was responsible for the climate’s abrupt turnaround and the subsequent effect on life forms. But the evidence for such an event has been under scrutiny the last few years, with much of it discredited, Pinter said. The final evidence its supporters pointed to were carbon spherules that contained nanodiamonds such as Ionsdaleite, a rarely observed hexagonal-shaped diamond formed by the impact.

Pinter’s team, which includes researchers from Washington University in St. Louis and Royal Holloway University of London, used transmission electron microscopy to examine samples from the western United States in search of the objects. Their research identified the objects as graphene and graphene/graphane oxide. They also demonstrated that previous research mislabeled those substances as hexagonal diamonds and cubic diamonds.

Pinter said with the final supporting evidence of the theory now impeached, scientists can return their attention to what really did happen during that time period, and how that resulted in so much change.

“This affected what is now Southern Illinois, too,” Pinter said. “There were mammoths and mastodons and possibly saber tooths roaming this area 15, 000 years ago. The vegetation was completely different, more a spruce-dominated land. But now we can get back to asking important questions about when and why this changed.”

The journal “Proceedings of the National Academy of Sciences” is publishing the findings under the title, “No evidence of nanodiamonds in Younger-Dryas sediments to support an impact event.”

http://news.siuc.edu/news/September1...0tjc10070.html

This is irrelevant... It's a different event. Check the dates.

[KanadaHye]

Re: Nasa's Glorious Failure

This is irrelevant... It's a different event. Check the dates.

There are tons of scientists that don't agree with the meteor extinction theory. Ask yourself 2 questions. What is there? What is not there?

What is there? The rapidly fossilized remains of trillions of drowned animals and plants.

What is not there? Meteorites!

There are no meteorites in the lower layers of the fossil record. If the evolutionary time frame was correct, there should be millions, if not billions, of meteorites in the fossil record. Some Iridium doesn't cut it.

[Siggie]

Re: Nasa's Glorious Failure

There are tons of scientists that don't agree with the meteor extinction theory. Ask yourself 2 questions. What is there? What is not there?

What is there? The rapidly fossilized remains of trillions of drowned animals and plants.

What is not there? Meteorites!

There are no meteorites in the lower layers of the fossil record. If the evolutionary time frame was correct, there should be millions, if not billions, of meteorites in the fossil record. Some Iridium doesn't cut it.

Umm... you do realize that when they hit, the largish meteors' impacts are like a nuclear explosions in the amount of energy released right? You expect the meteorite itself to survive that? They do find debris that has different enough proportions of certain elements that don't occur in those quantities on Earth though.

There's more than some iridium. You don't look at the supporting evidence and then insist it doesn't exist.
I'm going to close my eyes and insist you don't exist. Reasonable, huh?

[HotFizzixist]

Re: Nasa's Glorious Failure

Umm... you do realize that when they hit, the largish meteors' impacts are like a nuclear explosions in the amount of energy released right? You expect the meteorite itself to survive that? They do find debris that has different enough proportions of certain elements that don't occur in those quantities on Earth though.

There's more than some iridium. You don't look at the supporting evidence and then insist it doesn't exist.
I'm going to close my eyes and insist you don't exist. Reasonable, huh?

From britannica.com article on meteorites:

When meteoroids are sufficiently large—i.e.,100 metres to several kilometres in diameter—they pass through the atmosphere without slowing down appreciably. As a result, they strike Earth’s surface at velocities of many kilometres per second. The huge amount of kinetic energy released in such a violent collision is sufficient to produce an impact crater. In many ways, impact craters resemble those produced by nuclear explosions. They are often called meteorite craters, even though almost all of the impacting meteoroids themselves are vaporized during the explosion. Arizona’s Meteor Crater, one of the best-preserved terrestrial impact craters, is about 1.2 km across and 200 metres deep. It was formed about 50,000 years ago by an iron meteoroid that is estimated to have been roughly 50–100 metres across, equivalent to a mass of about four million tons. Myriad nickel-iron fragments and sand-grain-sized nickel-iron droplets have been found in and around the crater.