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.

The Conversation

Meteor Crater in Arizona. (Photo: Angle Schatz/Flickr)
Azeem Ward
Show Hide image

Living the Meme: What happened to Azeem Ward and his flute?

In the first of a new series investigating what happens to people after they become memes, we speak to Azeem Ward, whose flute recital went viral in 2015.

The Sixties had Woodstock. The Nineties had Lollapalooza. The Tens – and, if we’re being honest, just a single year of them – had Azeem's Senior Flute Recital.

If you were inactive on the internet between 12 and 16 May 2015, you’ll be forgiven for not knowing who Azeem Ward is. After setting up a Facebook page for his end of year flute performance, the University of California student was inundated with over 100,000 RSVPs from the United Kindom, along with multiple requests to fly to England and play (for no apparent reason) Darude’s “Sandstorm” in Nando’s. After international news coverage, Ward – as all memes inevitably do – appeared on Jimmy Kimmel Live! to discuss his newfound fame. On 16 May, he had to turn hordes of people away from the 500 seat recital hall, and over 55,000 individuals tuned into a livestream of the event. Then, Ward disappeared. Not from social media, and not from the world, but from the internet’s collective consciousness.

Search interest in "Azeem Ward" over time

“I’d say no,” answers Ward, when I ask him whether, one and a half years later, he still receives any special attention or has any fan interactions. “I’m just regular Azeem now, and I’m okay with that. Regular me is a more focussed person that is not reacting to things that are happening around me.”

Ward is Skyping me from his home in Iowa, where he is getting his master’s degree in flute performance. He spends his time composing flute beatbox songs, learning how to produce music, and teaching a class on flute fundamentals at the university. “A lot of [the students] here in Iowa know what happened but they don’t go like: ‘Oh my God! It’s Azeem!’. It’s just like, ‘Hey, what’s up man? I saw that one thing about you on Jimmy Kimmel’.”  

The original Facebook event page

Ward regained his anonymity when he moved to Iowa, as many of his fellow undergraduate students in California recognised him because he was on the local news. “But the whole viral thing was a UK thing,” he explains, “It wasn’t really around the whole US.”

An Azeem meme

Four months after his famed flute recital, Ward did come to the UK and toured the country to perform as part of various university freshers’ weeks. “That was a crazy time,” he says, “I was over there for five weeks and played 22 shows in 12 different cities, all the way from London to Scotland.” His concerts were popular, though most people came to take a selfie or ask about how the recital happened, and only a few wanted to talk to him about music. Still, Ward profited from the events. “We did make some pretty good money," he says, admitting he earnt around $5,000. 

Despite clearly enjoying this time, Ward seems unfazed that his viral fame is now over. His only regrets, he says, are that he didn’t make any connections in the music business while in the UK, and that he didn’t have any social media accounts set up before he went viral, so there was nowhere for people to go to listen to his music. “When you go viral people hold onto that rather than taking you seriously as a musician,” he says. “Sometimes it annoyed me but sometimes I realised that I wouldn’t be there in the first place if it wasn’t for going viral.”

Azeem now, photo courtesy of Azeem Ward

So what advice would Ward give to the next person who finds themselves, unwittingly, the object of the internet’s affection?

“I'd say don't lose sight of what you've already been doing in your life, like keep your focus. I'd say that sometimes in your head you're like ‘Oh man, I have to do this now’, but you've just got to stay focussed on your goals. When you have your own path and you go viral you have a lot of people asking you to do all these different things. It was pretty intense – I’m not used to having a lot of people look at me and my actions, so I was pretty anxious at first. In the end I realised that I came to do what I came to do, and I had to go do it.”

Although Ward doesn’t miss being internet-famous, it is clear that going viral had an impact on him. He recalls the peak of the madness with telling clarity, sharing specific details such as "256 people” clicked attending in "four hours", and “then 512”, before 12,000 people RSVP’d overnight. Mostly, however, he seems very grounded, though he acknowledges it was “out of control” and “really crazy”.

Perhaps Ward feels this way because he received little in the way of negativity or hate. He fondly discusses memes that were created and art that was drawn about him, and the support of his family and friends. “Even though there were a lot of silly things going on, I managed to make it positive for the school,” he says. “I had no haters. Everyone was like ‘Damn, Azeem. Good job, man’.”

One day, Ward hopes to come back to London, although he is wary of returning. Not because of his viral fame, nor the number of selfies he might have to take with Nando's customers, but because of Brexit. Our conversation, like all post-June conversations, turns swiftly to the topic, and Ward asks me about the economy. “I was thinking about trying to do a doctorate over in London, but if things aren't going to be so good in a few years...” 

Ward admits he wouldn’t be bothered if he never went viral again. “When I think of something going viral, I think it has a point in time where there’s so much interest and then it goes away. I’d like to produce material and the attention to keep going up.” So do you want to be famous, I ask? “Do I really want to be famous?” he ponders. “Being famous is okay, I guess. But I want to be is respected and appreciated.”

To listen to Azeem’s music visit or Like his Facebook page.

To suggest an interviewee for Living the Meme, reach out to Amelia on Twitter.

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