Scientists Say There’s A Geological Time Bomb Hidden Under Alaska – And It Could Be Catastrophic

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In the remote reaches of Alaska, scientists have bored a tunnel deep beneath the tundra. But their work has revealed something horrific, and now the remains of extinct animals peek out everywhere from the frozen ground. It’s a vast subterranean graveyard that has begun to thaw – triggering a time bomb that could have frightening consequences for humankind.

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Ensconced in the far northwestern corner of North America, Alaska has always been a wild and beautiful place. And even though the city of Anchorage is now home to some 300,000 people, much of the region is made up of small and scattered communities. There, it seems, life has changed little over the centuries.

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However, a worrying secret has laid buried for thousands of years in this stunning landscape of ice and snow. And now, it has the potential to wreak havoc across the Earth as we know it today. But what could this time bomb beneath the Alaskan wilderness be? Well, outside the city of Fairbanks, scientists have made some troubling revelations.

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In the 1960s researchers from the U.S. Army decided to dig a tunnel close to Fairbanks – the state’s second-largest city. And, apparently, the military’s goal was to study the natural phenomenon known as permafrost. This is a catch-all term for the type of frozen ground that stretches across some 85 percent of the entire state.

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According to scientists, permafrost impacts around 25 percent of the Northern Hemisphere. Consisting of substances such as gravel, sand and soil, such layers typically occur when the ground remains at freezing temperatures for more than a couple of years. And permafrost doesn’t just appear on land, either; it can also be found beneath the depths of our planet’s oceans.

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As you may expect, this phenomenon is more commonly found in regions where temperatures are seldom higher than 32° F, meaning there’s often permafrost in Eastern Europe, Russia, China, Greenland and Alaska. And while these frozen sections may be relatively shallow in some areas, they can also stretch for more than 3,000 feet.

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Today, scientists are aware that permafrost falls into two categories: continuous and discontinuous. With examples of that first group, one vast area – such as Siberia – is covered by a single sheet of frozen ground. Discontinuous permafrost, by contrast, is broken up into a number of different pieces. And while some of these expanses may melt seasonally, others remain present all year round.

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Over the years, both types of permafrost have contributed hugely to scientists’ understanding of our climate. Yet experts believe that these resources are dwindling. For example, National Geographic has claimed that during the course of the 20th century, the planet’s frozen layers rose in temperature by more than 40° F. And as time goes on, this situation could only grow worse.

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For those living in the Arctic, meanwhile, the permafrost poses some difficult challenges. Building structures on the frozen tundra can be tough, for example, and the heat from construction sometimes exacerbates the situation by causing the ground to thaw. But humans have adapted to these conditions over time, and now entire cities exist in some of the iciest corners of the Earth.

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When the Fairbanks tunnel was first hollowed out, moreover, the permafrost in the region had changed little in hundreds of years. Now, though, as temperatures rise around the world, the frozen ground beneath the Arctic is getting warmer. And as these areas begin to thaw, they could kick-start a catastrophic chain of events.

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In any case, the tunnel is certainly still relevant today. Currently, it forms part of the Cold Regions Research and Engineering Laboratory (CRREL), where scientists study the unique behavior of permafrost – including how it may react to climate change. And for experts such as U.S. Army Corps of Engineers geochemist Dr. Thomas Douglas, this work gives them the chance to take a fascinating peek into the past.

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You see, while some perceive the tundra as a wasteland, the permafrost is actually full of prehistoric remains that have stayed preserved in the frozen ground for thousands of years. And the evidence of this is clear in the Fairbanks tunnel. Some visitors have even reported seeing the bones and tusks of mammoths jutting out from the walls and floor there.

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The permafrost is like an entire ecosystem frozen in time – bursting with the remains of long-dead life. From extinct woolly rhinoceroses to ancient plants, practically everything that once walked or grew on this ground has been preserved in the frozen expanses beneath its surface.

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But despite the fascinating appeal of these remains, they also present a real problem. Like all other lifeforms, dead or alive, they are made from carbon – and lots of it. In 2018 Douglas told NPR, “The permafrost contains twice as much carbon as is currently in Earth’s atmosphere. That’s 1,600 billion metric tons.”

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And while this carbon is currently trapped in the permafrost, Douglas and his colleagues have begun to wonder what will happen when the Arctic’s frozen ground begins to melt. So, the team launched an experiment to find out – and the results have hinted at an alarming trend.

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During the investigation, scientists at CRREL drilled into the permafrost and removed sections of ice – each one coming in at around 5 inches long and 2.5 inches across. Then the experts took the samples to a laboratory, where they allowed them to slowly warm up. And before long, the team began to notice that something strange was happening.

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“This is material that stayed frozen for 25,000 years,” enthused Douglas. “And given the right environmental conditions, it came back [to life] again vigorously.” Amazingly, ancient bacteria had been suspended within the permafrost; as temperatures rose, though, they woke up and got to work.

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Yet this is not the first time ancient bacteria has been reanimated after a long spell in the ice. The phenomenon has also been witnessed in Russia, where according to The Daily Telegraph some 66 percent of the terrain is permafrost. And, unfortunately, the country is also experiencing some of the worst global warming around. In 2015 it was reported that temperatures in Russia are rising at a rate of more than twice that of anywhere else on the planet.

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Still, with so much permafrost to go around, residents have understandably long adapted to the icy conditions. In the city of Yakutsk, for example, buildings are traditionally constructed on stilts that bypass the constantly melting and refreezing active zone. Unfortunately, however, warming temperatures have meant that even these dwellings have become unstable.

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And in this chaotic environment, the bacterium Bacillus anthracis may be starting to raise its head once more. Typically associated with biological warfare, this substance leads to anthrax – a potentially lethal infection that once terrorized the frozen landscape of Siberia.

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According to experts, Bacillus anthracis spores form as part of a natural reaction within the soil. Then, when humans come into contact with this bacteria, they may develop nasty blisters that can lead to further complications. And while some communities have gone decades without an anthrax outbreak, melting permafrost is now releasing the infection back into the world.

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“Anthrax spores can stay alive in the permafrost for up to 2,500 years,” Yakutsk-based biologist Boris Kershengolts told The Daily Telegraph in 2019. “That’s scary, given the thawing of animal burial grounds from the 19th century. When they are taken out of the permafrost and put into our temperatures, they revive.”

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According to the British newspaper, a 2011 study has identified the parts of Siberia’s Yakutia region where anthrax outbreaks had occurred. And, alarmingly, these areas were also apparently found to be where warming was at its most extreme. In the Arctic, rising temperatures are similarly believed to be behind the first anthrax deaths there in seven decades.

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Back in Alaska, though, researchers noted that the resurrected bacteria began reacting with the dead animal and plant matter stored within the permafrost – transforming carbon into methane and carbon dioxide in the process. And as scientists know all too well, these are the very gases that are responsible for climate change.

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Up until now, Alaska has been known for absorbing more carbon dioxide from the atmosphere than it emits. But as the permafrost thaws, this process could be reversed. Indeed, in 2017 scientists in the north of the region observed the first evidence of this worrying trend.

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And if these extra carbon stores are released, it could spell disaster for the planet. At the moment, it’s thought that approximately 1,400 gigatons of the element are held in permafrost around the world. This total apparently represents around four times the level of carbon that humans have discharged into the air in the past 260 years. Even the atmosphere of our planet currently contains just half that amount.

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But ancient bacteria hasn’t been the only contributor to the release of greenhouse gases across Earth’s frozen regions. Melting permafrost can also expose underground reservoirs to the open air above, and methane can be expelled into the atmosphere through these new pathways.

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And while experts still concede that human activity is the biggest producer of greenhouse gases, melting permafrost is fast becoming a rival contender. It’s actually believed that the phenomenon has resulted in the annual release of between 1.2 and 2.2 million tons of emissions in recent years.

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For context, permafrost thaw produces as much greenhouse gas as the entire nation of Japan, according to the National Oceanic and Atmospheric Administration. And as the 21st century progresses, experts believe that the volume of carbon released in this fashion will continue to grow. Incredibly, these numbers are even expected to overtake those of the United States – at present the second-biggest carbon dioxide producer in the world.

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So, what exactly happens when large amounts of these gases find their way into the atmosphere? Well, the outlook appears grim from a climate change perspective. Essentially, substances such as carbon dioxide radiate energy downwards – thus warming the planet. And while such a process is a necessary one, its effects have been accelerating in recent years.

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If more carbon is released from melting permafrost, then, it will exacerbate a situation that is already spiraling out of control. In fact, experts believe that our planet may heat up by as much as 10° F over the next 100 years. And if this scenario comes to pass, Earth will look very different from the planet we know today.

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Just how worried do we need to be? Well, according to some scientists, the situation is a precarious one. In 2018 NASA chemist Charles Miller told NPR, “We have evidence that Alaska has changed from being a net absorber of carbon dioxide out of the atmosphere to a net exporter of the gas back to the atmosphere,” And with ancient bacteria poised to come back to life across the Northern Hemisphere, things could get even worse.

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“The analogy is that it’s a big train about to derail,” ecologist Dr. Merritt Turetsky, from the University of Guelph in Ontario, told the Toronto Star in 2011. “Once it begins, permafrost thaw occurs slowly, but you can’t stop it. [And] that lack of control makes anybody feel nervous.”

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Yet scientists are currently unsure as to how big of an impact this geological time bomb might have. For example, if there is a thaw, erosion could cause much of the resulting carbon to be washed away by the Arctic’s oceans. A warmer environment may also help new vegetation spring up across the tundra, and this flora in turn is likely to reabsorb some of the harmful gases.

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In the long run, though, there is little doubt that climate change will drastically alter the world we inhabit. And while we are yet to see just how much impact melting permafrost will have on the world as a whole, the phenomenon has already had a very noticeable effect on Earth’s frozen landscapes.

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Essentially, permafrost acts like an adhesive by sticking together the layers of rocks and minerals that make up the surface of our planet. Then, when this melts, the landscape may shift dramatically. Almost overnight, lakes can empty, rivers can change direction and shorelines can disintegrate. And in places where frozen water makes up more than three-quarters of the ground, the consequences have been extreme.

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In Alaska, for example, the melting permafrost has caused a drastic change in the local terrain. Areas that were once thick with vegetation have now flooded with meltwater, causing new lakes to form. In other locations, conversely, plants that were previously stunted are now thriving in the thawed ground.

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In the Northwest Territories of Canada, meanwhile, researchers observed a cliff that collapsed as a result of melting permafrost. And as the rocks crumbled, the specialists noted that a resulting waterfall drained a nearby lake – emptying some 800,000 gallons of water in two hours. Yes, these dramatic fluctuations can occur in a surprisingly short amount of time.

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And according to Turetsky, we should take such developments as a warning. In 2019 she told Anchorage Daily News, “It can happen super quickly, even in a matter of months. This has been a wake-up call to the climate science community. What has been happening at some of our field sites is a whole different ball game.”

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Ultimately, no one can be sure what the full effects of the thawing permafrost could be. Yet it’s this uncertainty that troubles experts such as Turetsky. And although she believes that measures must be taken to curb human-created emissions – and so hopefully stave off environmental disaster – the worry remains that it could all be too little, too late.

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And if the prospect of colossal carbon emissions isn’t scary enough, then you should be thinking about the danger that could come from the skies. You see, there’s at least one asteroid that seems to be on the way to Earth – and if it gets into our atmosphere, that could spell doom for humankind. Luckily, though, NASA has a plan to save future generations…

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Deep in outer space, a diamond-shaped asteroid is hurtling towards Earth. If the two bodies collide, the space rock – known as Bennu – is big enough to extinguish life on our planet. But the asteroid is not alone. No, a NASA probe has been chasing the massive space rock for years. And having caught up with the colossal asteroid, the craft is preparing to land on its rocky surface. It’s a high-risk maneuver that demands absolute precision, but it’s one that could help secure the safety of humankind.

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Approximately 66 million years ago, a large asteroid slammed into the Earth near Mexico’s Yucatán Peninsula. That in turn triggered a cataclysm – an extinction event that led to the loss of three-quarters of the planet’s biodiversity, including the dinosaurs. But the impact transformed the environment into one that allowed Homo sapiens to evolve and flourish. A similar asteroid collision today, however, would mean the end of human civilization as we know it.

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For decades, scientists have known that Earth faces the risk of a major asteroid collision. It’s more than a risk, in fact, as the chances of such a strike happening are 100 percent certain; it’s merely a question of when. And several Hollywood movies have, of course, already imagined the asteroid apocalypse – the 1998 box-office smash Armageddon, for instance. But while Armageddon is a light sci-fi adventure starring Bruce Willis and Ben Affleck, the threat of Bennu is real.

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So where has this potentially devastating space rock come from? Well, it’s thought that asteroids were forged in the same high energy crucible that gave birth to our solar system. These rocky bodies range in size from small pebbles to enormous hunks of stone measuring hundreds of miles across. Their creation – along with that of the Sun, planets and moons – came about approximately 4.6 billion years ago when an enormous molecular cloud containing dust and gas collapsed in on itself.

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Now, small pieces of asteroids and other space rocks sometimes fall to Earth. And although most such bodies burn up in the atmosphere as “shooting stars,” occasionally – around ten times a year – a small piece of rock makes it to the surface. Known as meteorites, these rocky fragments often leave a small impact crater. But unless you have the cosmic misfortune of being hit by one of these falling space rocks, they pose no serious threat to human life.

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An asteroid the size of Bennu is another matter, though. You see, the impact of such a large space rock would unleash kinetic energy equivalent to tens of thousands of atomic bombs. And the subsequent shockwaves would cause earthquakes and tsunamis. Meanwhile, the resulting dust cloud would probably cool the planet for hundreds of years – thereby devastating Earth’s ecology.

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There are thousands of space rocks currently traveling in close proximity to the Earth too – although “close” in this case refers to around 120 million miles out. Most such rocks are, in fact, concentrated in the area between Jupiter and Mars. But Bennu is one of 200 known asteroids with a solar orbit much like that of Earth, and one Bennu year is equivalent to 436 Earth days. What’s more, the body passes perilously close to our planet on a regular basis – once every half a dozen years.

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The asteroid is certainly of note, then, and scientists originally gave it the rather catchy name 1999 RQ36. Bennu’s new moniker, however, was conjured up in 2013 by nine-year-old Mike Puzio, who won a competition to rename the rock. And the youngster was inspired by NASA’s OSIRIS-REx probe. Indeed, Puzio thought that the craft looked like the neck and wings of the Egyptian deity Bennu – who is often represented in the form of a heron.

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At 1,650 feet wide, Bennu is a comparatively big asteroid. And the larger the asteroid, the easier it is to land a probe on it. Indeed, smaller space rocks – 650 feet across or less – tend to spin rapidly, making them unsuitable for landing on. With technological improvements, though, we may be able to explore a wider range of asteroids in the future.

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For now, though, Bennu is of particular interest to NASA, and the agency has sent OSIRIS-REx to learn more about the asteroid. An acronym for “Origins-Spectral Interpretation-Resource Identification-Security-Regolith Explorer,” OSIRIS-REx is an $800 million space probe tasked with tracking Bennu. And with the help of the craft’s sensitive detection instruments and cutting-edge robotics, NASA scientists hope to extract two ounces of sample material from the surface of the rocky body. The sample will then be brought back to Earth for further study.

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And there are good reasons why NASA wants to examine the sample on terra firma – the main advantage simply being that a far wider range of tests can be carried out back on Earth than in space. You see, while OSIRIS-REx boasts sophisticated technology, the most advanced scientific analyses require large, bulky equipment that cannot fit on a probe. But flying the sample home makes the mission riskier and more complicated, of course.

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However, even if OSIRIS-REx is successful, it won’t be the first time that a space craft has delivered an asteroid sample to Earth. Japan earned that accolade in 2010 with their Hayabusa spacecraft. And the probe’s successor, Hayabusa 2, is currently en route to the Ryugu asteroid.

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OSIRIS-REx, though, is part of NASA’s New Frontiers program – which uses smaller spacecraft to explore our local solar system. Other missions have included New Horizons and Juno, which have helped glean new information about Pluto and Jupiter. Meanwhile, the proposal for OSIRIS-REx was selected from a range of finalists in 2011.

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And having been given the green light, the mission is now well underway. The probe itself has five specific instruments for surveying and analyzing the surface of Bennu. The craft’s Visible and Infrared Spectrometer (OVIRS), for starters, will be used for detecting organic chemicals and minerals by measuring both near-infrared and visible light. You see, OVIRS identifies material properties by detecting the light frequencies absorbed by their molecular structure.

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Secondly, the probe’s Thermal Emission Spectrometer will measure the rock’s temperature. Like the OVIRS, this device will also locate concentrations of chemicals and minerals. And together, these two instruments will enable NASA scientists to map the surface of Bennu and choose the most interesting site to extract samples from.

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The third array of instruments is a high-resolution camera suite composed of three units: PolyCam, MapCam and SamCam. PolyCam will gather initial images of the asteroid as well as potential sample sites, and MapCam will then scour the rock for satellites and stitch together topographic maps. Finally, SamCam will film the extraction of the sample.

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Meanwhile, the OSIRIS-REx Laser Altimeter (OLA) will conduct a detailed scan of Bennu’s surface. And the data that the instrument collects and relays back to Earth will be used to create extremely detailed models of the asteroid in 3D. Interestingly, similar technology was recently used to reveal the location of Mayan pyramids in the jungle.

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Finally, the probe is also fitted with a Regolith X-ray Imaging Spectrometer (RExIS), which will detect the X-rays coming from the asteroid. And the results collected by this device will contribute data to a map of the rock’s elemental properties. Specifically, the information gathered by the RExIS will reveal the atomic structure of the asteroid.

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OSIRIS-REx should help experts discover new information about our solar system, then. Indeed, just as the fossil record contained within the strata of the Earth underpins our knowledge of geological time, so the asteroids in our solar system are vital to our understanding of cosmic time. And to this end, scientists hope that by studying material created at the dawn of the Sun, we will gain new insights into planetary formation.

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NASA is also interested in the theory that biological life did not begin in Earth’s primordial ocean; rather, life migrated to our planet on an asteroid. And interestingly, Bennu appears to have a particularly high level of carbon-based components. Further analyses of the space rock’s composition may yet provide new insights on the origins of life, then.

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There’s the asteroid’s monetary worth too. That’s right: the rock could be a valuable new source of resources. “The mission will develop important technologies for space exploration that will benefit anyone interested in exploring or mining asteroids,” Dante Lauretta, OSIRIS-REx’s Principal Investigator, explained in a space agency press statement in 2013.

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Whether that interested party is a private enterprise or a space agency such as NASA is hard to say, though. But given the recent growth of private investment in the space sector, it is not hard to imagine a future where asteroids are regularly mined for fuel or metallurgical resources. It may, in fact, one day be cheaper to mine asteroids in space than to mine the Earth.

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Above all, though, the data gleaned from the mission will enable scientists to better predict the trajectories of asteroids – and, presumably, influence their respective courses. But one possible application of such knowledge could be terraforming – the intentional alteration of a planetary body in an attempt to make it habitable. In 2017, for example, scientists from the Lake Matthew Team proposed a scheme called the Mars Terraformer Transfer. And believe it or not, the plan involved crashing an asteroid into the planet.

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You see, the scientists say that such a collision would cause the Martian bedrock to heat up and release its frozen groundwater. This, in turn, would create a lake lasting for millennia. And it’s theorized that the water from the new lake could then be used to supply a city-sized colony – effectively side-stepping the big technical challenges of terraforming an entire planet.

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Of course, understanding the orbit of asteroids such as Bennu is also necessary for averting collisions with Earth. In Armageddon, a plucky band of oil rig workers save the day by planting a nuclear device inside the rogue space rock and blowing it to pieces. And in the future, probes such as OSIRIS-REx may well be able to carry out such an operation but with more precision.

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OSIRIS-REx could be crucial to the future of our planet, then. And having launched in September of 2016, the probe’s first maneuver involved setting up for a gravity assist before performing a flyby of Earth. This slingshot strategy – intended to add speed for the onward voyage – saw the craft use our planet’s gravitational pull to catapult itself into space. So, just over a year after leaving, the probe caught a brief glimpse of Earth before heading onwards to Bennu.

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And it seems that the probe’s flyby of Earth went perfectly. It brought the spacecraft within 11,000 miles of Antarctica, in fact, and caused it to accelerate by an additional 8,500 miles per hour. What’s more, before departing for the distant asteroid of Bennu, OSIRIS-REx took some haunting images of the Earth and the Moon.

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Then, on December 3, 2018, OSIRIS-REx came within sight of its target. It marked the end of a 27-month chase that had taken the probe over a billion miles through space. Now, though, NASA scientists would have to perform the tricky task of putting the probe into orbit around Bennu.

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To complete the move, the expert team first had to take detailed measurements of the rock’s shape and mass. “Maneuvering around a small body that basically has no gravity is very challenging,” Heather Enos, Deputy Principal Investigator for OSIRIS-REx, explained to Space.com. “So, we do have to get a little more information to proceed every step of the way.”

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But NASA safely placed OSIRIS-REx into orbit around the asteriod on the last day of 2018. And in doing so, the space agency established a couple of records. Firstly, Bennu became the smallest space rock ever to be orbited by a spacecraft. Secondly, the probe broke the record for the nearest orbit of a body that small in space; and at one point, the craft traveled just a single mile from the asteroid’s surface.

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Locked in orbit around Bennu, then, OSIRIS-REx has since been conducting surveys of the asteroid’s surface. The probe will generally complete flybys at distance of around four miles and has been charting the asteroid’s north and south poles as well as its equator. And scientists are now analyzing the data to make future decisions about the craft.

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Of course, the biggest decision concerns where exactly to land the probe. The sample site will, in fact, only be selected after a year and a half of data gathering and analysis. Mission managers will then present two potential landing sites in July 2020, and the winning location will be selected shortly thereafter. And after this decision has been made, OSIRIS-REx will carry out its next important task.

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Yes, the probe will then move in to collect a sample. However, the landing will be extremely brief. So fleeting, in fact, that OSIRIS-REx scientists have compared it to a kiss, lasting just a couple of seconds. That short period, though, should be enough for the craft to acquire its sample; at least, that’s the idea behind its Touch-And-Go Sample Acquisition Mechanism (TAGSAM).

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Indeed, TAGSAM does the work of digging and collecting rock. Using blasts of nitrogen gas, the device fractures the surface of the asteroid to release broken rock and dust, which is then collected inside a sample chamber. And to allow for several attempts at obtaining a sample, the probe carries three gas-filled containers.

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For the mission to be a success, then, NASA must acquire a minimum of two ounces of asteroid material. However, to compensate for any measuring errors, they will attempt to gather around five ounces. And should the mission demand it, TAGSAM actually has the capacity to carry an additional 70 ounces.

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Once the sample has been collected, OSIRIS-REx will commence its long journey home. The return trip is scheduled to start in March 2021 and will take some two and a half years to complete. Then, in September 2023, the probe will dispatch its cargo of asteroid rock. And if all goes to plan, the sample should parachute to Earth and land somewhere in the deserts of Utah.

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But while Bennu is certainly capable of inflicting disaster on Earth, the asteroid is unlikely to ever actually hit our planet. In fact, according to NASA, there is a one-in-2,700 chance that the rock will hit Earth in the 22nd century’s final quarter. For that to happen, though, the asteroid’s present track would have to change during its 2,135th orbit.

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There is, however, still an important reason for NASA scientists to conduct a thorough risk assessment of the rock: the Yarkovsky effect. This theory – discovered by Polish engineer Ivan Yarkovsky – refers to the way an asteroid’s path can be altered over time by the Sun heating the rock’s surface. An unpredictable Yarkovsky effect, then, could potentially cause Bennu to be redirected towards Earth.

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But even if Bennu were to collide with Earth, a hypothetical doomsday impact is actually a matter of dispute. Yes, while British tabloid The Sun has compared a potential impact to “80,000 Hiroshima atomic bombs,” experts believe the destruction would likely be limited to a more localized area. An extinction event is, therefore, unlikely.

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Nonetheless, the possibility of an asteroid colliding with the Earth at some point in the future is almost completely certain. Whether or not humans will be around to experience it, much less have the technology to avert it, is less certain. But, in any case, there will always be a sensible, powerful and scientific argument for studying space rocks.

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