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)
Curtis Holland
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Living the Meme: What happened to the "Bacon is good for me" boy?

Eight years after becoming a meme, the boy dubbed "King Curtis" explains what life is like now.

It is hard to pinpoint the one quote that made Curtis Holland a viral sensation. When he appeared on Wife Swap eight years ago, Holland – aka King Curtis – battled ferociously with his replacement mum Joy, who wanted to rid his home of unhealthy snacks. “Chicken nuggets is like my family,” he said at one point; “I don’t wanna be skinny! I wanna be fat and happy,” he said at another; during one particularly memorable scene he wrote “I am not lisning to your rules” on a Post-It note.

“Bacon is good for me!” perhaps comes out top. The quote – like all the others – has become an internet meme, featured in screenshots and gifs, but has additionally been remixed into a song. The original clip has over ten million views on YouTube. Now aged 15, Holland is speaking to me from his home in Vanceboro, North Carolina. “Oh yes!” he says when I ask if he still likes bacon. “Every morning my mum gets up and we all cook bacon together.”

 

Before speaking to Holland, I had eaten (ten) chicken nuggets for my tea, but when I tell him this I'm not sure he believes me. “I know some people say this just to say it,” he says, before admitting he himself had eaten some that day. “This morning that's exactly what I had.”

Holland speaks in a straightforward matter-of-fact tone that is just as endearing now as it was when he was seven. He is incredibly respectful – calling me “ma’am” at least three times – and is patient when I struggle to decipher his thick Southern accent (“pennies” for example, becomes “pinnies”, “cars” is “curs”).

“We live in a small community, and a lot of people say that I'm the movie star,” says Holland, when I ask him to explain how life has changed since appearing on TV. When I ask about life after becoming a meme, Holland is less sure. “I mean I don't have a Twitter but a lot of people say that I'm up there just about every week,” he says (in reality, the clip of his appearance alone – never mind gifs, quotes or screenshots – is tweeted multiple times a day).

There is one meme moment, however, that Holland definitely didn’t miss. In 2015, Pretty Little Liars actress Lucy Hale posted a photo to Instagram asking for an update on his life. In response, Holland created a YouTube video asking for money to rebuild cars and confidently saying “Someday I’ll get my own bacon brand.” The video got over 400,000 views.

“I went viral for I think three or four days and I was on the most views on YouTube,” explains Holland. “That was pretty cool for me, to see when I look on YouTube there my face is.” How did it make him feel, I ask? “It makes you feel good inside. One day I come home from school and I was mad, and I can tell you it just made me feel really good inside to see that [the video] was pretty much one of the top in basically the world.”

Despite enjoying the attention, Holland has no aspirations to be a TV or internet star again. He is part of an organisation called the Future Farmers of America (FFA), and plans to go to his local community college before becoming a welder. “There’s a few know-it-alls in the community,” he says, “They just say it’s crazy how you went and did all that and now you’re not going on in the movie field. That’s not something I’m really interested in.”

Yet although Holland says it’s “time to move on a little bit”, he also admits he would be open to any offers. “A lot of people say well why don’t you just get up with a bacon company and do commercials or something… I mean I wouldn’t mind doing that if they came and asked me.” After Wife Swap, a company did come and film a pilot for Holland’s own show, but it never amounted to anything. “I mean you'd be lucky to get on TV once in your whole life and I feel like I really enjoyed it when I was up there,” he says when I ask if this was disappointing.

All of this means that Holland hasn’t made much money from his viral fame. Unlike other memes I’ve spoken to, he hasn’t earned hundreds of thousands of dollars. “I believe I got 150 bucks,” he says of his “Update” YouTube video, “All the other stuff like the ‘Bacon is good for me’ songs, they’ve [the creators] made $75,000 and that’s a lot of money putting away."

“I mean it don’t annoy me because it ain’t my fault; it’s nobody’s fault in the situation. They found a way around the system,” he says when I ask if he’s annoyed at others’ making money at his expense.

Nowadays, Holland is still recognised when he is out and about, and says he has signed over one thousand autographs in his life (once he was wary of a neighbourhood policeman who was asking him to sign a parking ticket, before he realised he simply wanted an autograph). “I don’t get sick of it, but of course you’ve got a few people that want to be rude about what you’re doing.

“I really don’t care, I’m a really upbeat kind of person. If there's somebody in a computer screen telling me something that means nothing, you know?”

For Holland, then, the good outweighs the bad. Apart from being asked after by Lucy Hale, his favourite thing about going viral is that he gets to make people laugh. “If I can go up to somebody and make their day and make them smile, I feel like I’ve done a great thing,” he says.

I end the interview with Holland like I end all of my interviews with memes: by asking him if there’s anything he would like to say – a message he’d like to get out there, or a misconception he’d like to clear up – now that he has the chance.

“Oh nothing I've got to say,” he begins, “except bacon is still good for me.”

 “Living the Meme” is a series of articles exploring what happens to people after they go viral. Check out the previous articles here.

To suggest an interviewee for Living the Meme, contact Amelia on Twitter.

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