Meteorite impacts leave behind time-capsules of ecosystems

Glass beads that form inside hot meteors as they fall to Earth capture particles from the atmosphere, creating a kind of permanent record of historic climates.

Meteorite impacts can be very destructive. One that fell in Mexico around 66m years ago created a 180km crater and caused the extinction of dinosaurs while spewing debris and molten rock into the air. Now, in what is a fascinating tale of serendipity, researchers have found that these events don’t entirely destroy all traces of life at the site of impact. Molten rocks can capture and preserve organic matter as they cool down to form glass beads.

When a meteor enters Earth’s atmosphere, the air around the meteor gets very quickly compressed causing it to heat up, scorching everything in its path. Most of the time that is where the story ends, as the meteor burns up in the sky as a “shooting star”. But sometimes it is big enough to reach all the way to the surface and transfer its remaining energy to the ground.

This energy is dissipated, as mild earthquakes, sound shockwaves – but mostly as heat. The heat energy can be so great that it melts rocks on the surface and hurls them up in the atmosphere. Anything that comes in contact with this molten rock would presumably get burnt, leaving nothing but rocky material that cools down in the atmosphere, forming glass beads and tektites (gravel-sized natural glass). This is what City University of New York researcher Kieren Howard assumed, but he was able to show that his assumptions were wrong.

For his PhD, Howard was studying the glass beads and tektites found near the Darwin crater in Tasmania. The 1.2km wide crater was created by a meteorite impact about 800,000 years ago.

The natural glass formed during cooling is (as implied by the term glass) not crystalline. Instead of a regular arrangement of atoms, the atoms inside it are randomly arranged. Howard’s analysis, however, kept showing the presence of crystals. At first, he dismissed this as a problem with the machine or with his method of analysis. But when it kept showing up, as a good scientist, he thought he should ask an expert to look at his data.

“This is unusual,” says Chris Jeynes, a physicist at the University of Surrey. “If there were indeed crystals, then it was the result of uneven cooling, which can occur when something gets trapped inside these glass beads.”

Jeynes used proton-beam analysis, a method to peer inside the glass to reveal its elemental make-up. Inside he found carbon. “Howard had no idea what his samples were, and he was very surprised when I told him,” Jeynes says.

The natural glass formed should contain only silicon, titanium, oxygen and other metallic elements in trace amounts. Detection of carbon meant that there was some organic matter inside. The only hypothesis was that, somehow during the formation of these glass beads, they captured organic matter that was floating in the atmosphere. That organic matter might have already been in the air, but it might also include material thrown up by the impact.

Howard then went to another expert to break open these glass beads and reveal what the carbon-rich matter was. It turned out that it included were cellulose, lignin and other biopolymers. This meant that somehow this matter, which originated from plants, had survived the temperature of more than 500°C, which is what the molten rock would have reached before cooling into a glass bead. Usually these temperatures will break down the organic matter, but clearly it didn’t in this case.

Mark Sephton, a geochemist at Imperial College London, was surprised and pleased: “What the results show is that these glass beads can capture an aliquot of the atmosphere of the planet at impact. It is like a time capsule of that ecosystem.” These results are published in Nature Geoscience.

The implications are enormous. It shows that other meteorite impacts, like the one that wiped out the dinosaurs, could have created such time capsules too. Sephton is now working on finding glass beads from other impact sites to reveal information about Earth’s ancient atmosphere.

This method of analysis means that we could also go looking for similar beads on other planets, like Mars, where meteorite impacts are common. They could also reveal vital information about the past atmosphere of those planets. Maybe they captured organic matter – if it ever existed there.

“We would not know any of this if it wasn’t for Howard,” Jeynes says, adding that Howard’s persistence to find out what “the wrong results” led the researchers to a phenomenon that nobody knew existed.

This article was originally published at The Conversation. Read the original article.

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Meteor Crater in Arizona. (Photo: Angle Schatz/Flickr)
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"They’re turning the frogs gay": The psychology behind internet conspiracy theories

Conspiracy theories are appearing on both the political left and right. 

They’re turning the frogs gay.

If you have ever watched a video by the internet’s premier conspiracy theorist, Infowars’ Alex Jones, you will know that this is an undeniable fact. Chemicals in the water are turning the (frigging) frogs gay.

The blatant absurdity of this conspiracy theory (which scientist is perving on homosexual amphibians, anyway? Stop them) makes it one of the most widely mocked and memed of Jones’ outbursts. Yet despite the ridiculousness of the red-faced ranter, he has a large and vocal fan base that even includes the 45th president of the United States himself.

We seem to be living in an era where conspiracy theories are booming. From Hillary Clinton’s paedophile pizza parlour, to Russian hackers, Red Pillers, Obama's communist coup and Trump’s 4D Chess – the internet has been flooded with conspiracies from both the Left and Right. Dr Robert Bartholomew, a sociologist who specialises in mass delusions, believes that social media has exacerbated conspiracy culture.

“We now live in a niche world, making it easier for people to construct their own reality - a world as they want it to be, not as it is,” he says. “A person who believes that Obama wasn’t born in the US can just visit sites that reinforce his or her beliefs." Batholomew explains that because of the internet, conspiracies can be passed on “at the speed of light”, while other experts have noted that emotions can also spread online, in a process known as “emotional contagion”. 

Yet though social media helps conspiracies to spread, the psychology behind them is age-old.

“Conspiracy theories are a product of our psychology and our psychology doesn’t really change over time,” says Dr Robert Brotherton, author of Suspicious Minds: Why We Believe Conspiracy Theories. “A certain proportion of people have always been receptive to conspiracy theories.” But who are these people – and what happens to make them fervently believe in gay frogs?

Brotherton emphasises that the psychological biases at work in conspiracy theorists’ minds are biases that we all possess to some extent. The “proportionality bias” means that if something big happens, we intuitively assume that something big must have caused it. Some of us can accept when this isn’t the case – when a lone gunman, for example, is responsible for assassinating the president from a grassy knoll – but others go looking for alternative explanations.

Humans also have a propensity to seek patterns, so we bend over backwards to connect unrelated facts (side note: why do the two psychologists thus far in this piece have remarkably similar names? Is there a psychologist Illuminati?).

“Confirmation bias” also means that we accept information that confirms our beliefs and ignore that which doesn’t. Once these biases lead someone towards a conspiracy theory, they might develop a “conspiracy worldview”, whereby everything becomes suspicious. Brotherton explains, for example, that after the Watergate scandal was exposed, conspiracy theorists weren't vindicated like you would expect - but instead believed that the official narrative was a cover-up and that Nixon was set up. 

A Pizzagate post on 4Chan, outlining alleged patterns and meanings

Yet though the psychology behind conspiracies is timeless, Brotherton does note that certain factors exacerbate our willingness to believe. And this credibility is not limited to right-wing Americans.

“One of the things I think that is most revealing is how quickly conspiracy fears have shifted to the Left, especially in the States, since the election,” he says. The night before the election, videos spread on right-wing social media profiles claiming to show that electronic voting machines were rigged to vote for Clinton. When Trump won, Democrats began to believe that Russians had hacked the voting machines in favour of Trump (though claims Russia manipulated the election are rooted in fact, there is no evidence they tampered with the actual count).

 

A Pizzagate meme

Brotherton explains that cognitive dissonance is to blame.  “In an election, if you voted for the losing candidate, that makes you feel kind of bad because it’s not what you wanted, and makes you look kind of silly, like why would you vote for the loser?"

The most obvious way to reason this out is to accept the candidate wasn't so good, and agree more with the other side.

"Obviously that’s not what happens at all," says Brotherton. Instead, he argues, we tend to go in the other direction. Instead of admitting that our candidate lost because they had flaws, we theorise about hacking and rigging in order to feel as though we were right all along.

A false claim about Donald Trump's administration

Yet conspiracy theories do continue to spread among the far right as well as the left, despite their electoral gains. Dr Mike Wood, a psychology lecturer and expert in the techniques used by conspiracy theorists online, explains that those with extreme political views might still be drawn towards conspiracy theories, even when they gain some power.

This is because their extreme position means they are still unlikely to get to accomplish what they want to do. "They have to rationalise that in some way," Wood says. "Often that leads to conspiracy theories.”

A Pizzagate meme

Alienation, a lack of control, and uncertainly are all facts that lead someone towards a conspiracy worldview, explains Wood. As he puts it: “basically conspiracy theories are a way to try and make sense of the world that in that moment doesn’t particularly make sense.” According to Wood, victims of social exclusion do tend to take conspiracy theories more seriously.

“If the world seems like a very random and kind of capricious place where things don’t particularly make sense and you can’t really control what's going on, that's when conspiracy theories are at their strongest," he says. Conspiracy theories "allege that things that are happening are basically controllable". 

It is hard to say whether any of this is at work in the mind of Conspirator-in-Chief Donald Trump. The President has previously spread information from Jones’ Infowars, most notably when he claimed three million votes in the election were cast illegally. “I won the popular vote,” he tweeted alongside this alleged fact, perhaps attempting to explain away his own cognitive dissonance. Yet whether or not Trump believes the conspiracies he spreads, the psychologists I speak agree on one thing. Having such a high-profile figure spreading conspiracies means they're not going away any time soon.

Amelia Tait is a technology and digital culture writer at the New Statesman.