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.”
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.
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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Scientists Say There’s A Geological Time Bomb Hidden Under Alaska |
“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.
Yet this is not the first time ancient bacteria have been reanimated
after a long spell on 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 warmings 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.
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.
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.
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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Scientists Say There’s A Geological Time Bomb Hidden Under Alaska |
“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.”
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.
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.
Unexplained Phenomena Keep Suggesting the Universe Isn’t What We Thought
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.
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.
But ancient bacteria haven’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.
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.
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.
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.
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.
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.
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.”
We just found a source for one of the most mysterious phenomena in astronomy
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.
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.
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.
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.
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.
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.”
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.
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 the plan to save future generations…
Deep in outer space, a diamond-shaped asteroid is hurtling toward
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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Scientists Say There’s A Geological Time Bomb Hidden Under Alaska |
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.
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.
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.
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.
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.
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.
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.
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.
For now, though, Bennu is particularly interesting 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.
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.
However, even if OSIRIS-REx is successful, it won’t be the first time
that a spacecraft has delivered an asteroid sample to Earth. Japan earned that
accolade in 2010 with its Hayabusa spacecraft. And the probe’s successor,
Hayabusa 2, is currently en route to the Ryugu asteroid.
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.
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.
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.
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.
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.
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.
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.
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 into the origins of life, then.
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.
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.
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.
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.
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 saves 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.
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.
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.
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.
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.”
But NASA safely placed OSIRIS-REx into orbit around the asteroid 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.
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 a 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.
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.
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 few 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).
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.
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
demands it, TAGSAM actually has the capacity to carry an additional 70 ounces.
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.
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.
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 toward Earth.
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.
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.
Hmmm. "while some of these expenses may melt seasonally" I think they meant "expanses" not "expenses" .
ReplyDeleteThis article reminds of the scene in Jurassic Park where Laura Dern has her arms deep in triceratops dung. It’s a massive pile of crap.
ReplyDelete"And if these extra carbon stores are released, it could spell disaster for the planet. "
ReplyDeleteThe Planet will be just fine. Humans on the other hand had better learn to adapt.
Earth as been much colder and also much warmer in it's history with both conditions happening in complete disregard whether humans or any other life for that matter survived.
A human centric view will only blind us to what will need to be done or what might be able to be done.
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