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)
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It’s 2016, so why do printers still suck?

Hewlett Packard recently prevented third-party cartridges from working in their printers, but this is just the latest chapter of home printing's dark and twisted history. 

In order to initiate their children into adulthood, the Sateré-Mawé tribe in the Brazilian Amazon weave stinging ants into gloves and ask teenage boys to wear them for a full ten minutes. The British have a similar rite of passage, though men, women, and children alike partake. At one point in their short, brutal little lives, every citizen must weep at the foot of a printer at 2am, alternatively stroking and swearing at it, before falling into a heap and repeating “But there is no paper jam” 21 times.

There are none alive that have escaped this fate, such is the unending crapness of the modern home printer. And against all odds, today printers have hit the news for becoming even worse, as a Hewlett Packard update means their machines now reject non-branded, third-party ink cartridges. Their printers now only work with the company’s own, more expensive ink.

Although it’s surprising that printers have become worse, we’re already very used to them not getting any better. The first personal printers were unleashed in 1981 and they seemingly received the same treatment as the humble umbrella: people looked at them and said, “What? No, this? No way this can be improved.”

It’s not true, of course, that printing technology has stagnated over the last 35 years. But in a world where we can 3D print clitorises, why can’t we reliably get our tax returns, Year 9 History projects, and insurance contracts from our screens onto an A4 piece of paper in less than two hours?

It’s more to do with business than it is technology. Inkjet printers are often sold at a loss, as many companies decide instead to make their money by selling ink cartridges (hence HP’s latest update). This is known as a “razor and blades” business model, whereby the initial item is sold at a low price in order to increase sales of a complementary good. It explains why your ink is so expensive, why it runs out so quickly, and the most common complaint of all: why your cyan cartridge has to be full in order to print in black and white.

But technology is complicit in the crime. HP’s new update utilises the chips on ink cartridges to tell whether a refill is one of their own, and have also previously been used to region-block cartridges so they can’t be sold on in other countries. Those little chips are also the thing that tells the printer when your ink is empty. Very good. Fine. Except in 2008, PC World found that some printers will claim the cartridges are empty when they are actually nearly half-full.

Back to business. Because this profit models means companies sell printers for so little, quality inevitably suffers. If they’re not selling them for much, companies will naturally try to keep the costs of making their printers down, and this is the reason for your “Load paper in tray two”s, your “Paper jam”s and your “Would you like to cancel this print job? Nope, sorry, too late, here are 100 copies.”

So why are printers bad at networking? This isn’t a set up to a lame joke (unless the joke is, of course, your life as you try to get your wireless printer and your PC to connect). There doesn’t seem to be a definitive answer to this, other than the fact that Bluetooth is still fairly patchy anyway. Some errors, just as you suspected, happen for no bloody damn good bloody reason at all.

On a bigger scale, the printers in your office are difficult because they work harder than you ever have. It’s a stressful job, for sure, and this naturally comes with errors and jams. The reason they are so hard to fix after the inevitable, however, again comes back to capitalism. Because printers don’t have a universal design, most companies will protect theirs, meaning you can’t know the specifics in order to fix a device yourself. This way, they also make money by sending out their own personal technicians.

Thankfully, although every personal printer you’ve ever bought seems to be on collaborative quest to drive you to madness, there is an easy fix. Buy a laser printer instead. Though the device and the replacement toner cartridges are more expensive, in the long-run you’ll most likely save money. In the meantime, there's only one solution: PC load letter. 

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