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Antarctica melting: Journey to the 'doomsday' glacier – BBC News

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The images are murky at first.

Sediment sweeps past the camera as Icefin, a bright yellow remotely operated robot submarine, moves tentatively forward under the ice.

Then the waters begin to clear.

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Icefin is under almost half a mile (600m) of ice, at the front of one the fastest-changing large glaciers in the world.

Suddenly a shadow looms above, an overhanging cliff of dirt-encrusted ice.

It doesn’t look like much, but this is a unique image – the first ever pictures from a frontier that is changing our world.

Icefin has reached the point at which the warm ocean water meets the wall of ice at the front of the mighty Thwaites glacier – the point where this vast body of ice begins to melt.

The ‘Doomsday’ glacier

Glaciologists have described Thwaites as the “most important” glacier in the world, the “riskiest” glacier, even the “doomsday” glacier.

It is massive – roughly the size of Britain.

It already accounts for 4% of world sea level rise – a huge figure for a single glacier – and satellite data show that it is melting increasingly rapidly.

There is enough water locked up in it to raise world sea level by more than half a metre.

And Thwaites sits like a keystone right in the centre of the West Antarctic Ice Sheet – a vast basin of ice that contains more than 3m of additional potential sea level rise.

Yet, until this year, no-one has attempted a large-scale scientific survey on the glacier.

The Icefin team, along with 40 or so other scientists, are part of the International Thwaites Glacier Collaboration, a five-year, $50m (£38m) joint UK-US effort to understand why it is changing so rapidly.

The project represents the biggest and most complex scientific field programme in Antarctic history.

You may be surprised that so little is known about such an important glacier – I certainly was when I was invited to cover the work of the team.

I quickly discover why as I try to get there myself.

Snow on the ice runway delays my flight from New Zealand to McMurdo, the main US research station in Antarctica.

This is the first of a whole catalogue of delays and disruptions.

It takes the science teams weeks just to get to their field camps.

At one stage, the entire season’s research is on the point of being cancelled because storms stop all flights to West Antarctica from McMurdo for 17 consecutive days.

Why is Thwaites important?

West Antarctica is the stormiest part of the world’s stormiest continent.

And Thwaites is remote even by Antarctic standards, more than 1,000 miles (1,600km) from the nearest research station.

Only four people have ever been on the front of the glacier before and they were the advance party for this year’s work.

But understanding what is happening here is essential for scientists to be able to predict future sea level rise accurately.

The ice in Antarctica holds 90% of the world’s fresh water, and 80% of that ice is in the eastern part of the continent.

The ice in East Antarctica is thick – more than a mile thick on average – but it rests on high ground and only creeps sluggishly to the sea.

Some of it has been around for millions of years.

Western Antarctica, however, is very different. It is smaller but still huge, and is much more vulnerable to change.

Unlike the east it doesn’t rest on high ground. In fact, virtually the whole bed is way below sea level. If it weren’t for the ice, it would be deep ocean with a few islands.

I’ve been in Antarctica five weeks before I finally board the red British Antarctic Survey Twin Otter that takes me to the front of the glacier.

I will be camping with the team at what is known as the grounding zone.

They are camped on the ice above the point where the glacier meets the ocean water, and have the most ambitious task of all.

They want to drill down through almost half a mile of ice right at the point where the glacier goes afloat.

No-one has ever done that on a glacier this big and dynamic.

They will use the hole to get access to the sea water that is melting the glacier to find out where it is from and why it is attacking the glacier so vigorously.

They do not have long.

All the delays mean there are just a few weeks of the Antarctic summer left before the weather starts to get really bad.

As the members of the drilling team set up their equipment, I help out with a seismic survey of the bed beneath the glacier.

Dr Kiya Riverman, a glaciologist at the University of Oregon, drills down with an ice auger – a large spiral stainless-steel drill bit – and sets small explosive charges.

The rest of us dig holes in the ice for the “georods” and “geophones” – the electronic ears that listen to the echo of the blast that bounces back from the bedrock through the layers of water and ice.

Thwaites is sitting on the seabed

The reason the scientists are so worried about Thwaites is because of that downward sloping submarine bed.

It means the glacier gets thicker and thicker as you go inland.

At its deepest point, the base of the glacier is more than a mile below sea level and there is another mile of ice on top of that.

What appears to be happening is that deep warm ocean water is flowing to the coast and down to the ice front, melting the glacier.

As the glacier retreats back, yet more ice is exposed.

It is a bit like cutting slices from the sharp end of a wedge of cheese.

The surface area of each one gets bigger and bigger – providing ever more ice for the water to melt.

And that is not the only effect.

Gravity means ice wants to be flat. As the front of the glacier melts, the weight of the vast reservoir of ice behind it pushes forward.

It wants to “smoosh out,” explains Dr Riverman. The higher the ice cliff, she says, the more “smooshing” the glacier wants to do.

So, the more the glacier melts, the more quickly the ice in it is likely to flow.

“The fear is these processes will just accelerate,” she says. “It is a feedback loop, a vicious cycle.”

Doing science of this scale in such an extreme environment is not just about flying a few scientists to a remote location.

They need tonnes of specialist equipment and tens of thousands of litres of fuel, as well as tents and other camping supplies and food.

I camped on the ice for a month, some of the scientists will be out there for far longer, two months or more.

It took more than a dozen flights by the US Antarctic programme’s fleet of huge ski-equipped Hercules cargo planes just to get the scientists and some of their cargo to the project’s main staging post in the middle of the West Antarctic Ice Sheet.

Then smaller planes – an elderly Dakota and a couple of Twin Otters – ferried the people and supplies on to the field camps, hundreds of miles down the glacier towards the sea.

The distances are so great they needed to set up another camp halfway down the glacier so the planes could refuel.

The British Antarctic Survey’s contribution was an epic overland journey that brought in hundreds of tonnes of fuel and cargo.

Two ice-hardened ships docked alongside an ice cliff at the foot of the Antarctic Peninsula during the last Antarctic summer.

A team of drivers in specialist snow vehicles then dragged it more than a thousand miles across the ice sheet through some of the most inhospitable terrain and weather on earth.

It was tough going, the top speed was just 10mph.

Drilling through the ice

The scientists at the grounding zone camp plan to use hot water to drill their hole through the ice.

They need 10,000 litres of water, which means melting 10 tonnes of snow.

Everyone sets to work with spades, hefting snow into the “flubber” – a rubber container the size of a small swimming pool.

“It’ll be the most southerly jacuzzi in the world,” jokes Paul Anker, a British Antarctic Survey drilling engineer.

The principle is simple – you heat the water with a bank of boilers to just below boiling point and then spray it onto the ice, melting your way down.

But drilling a 30cm hole through almost half a mile of ice at the front of the most remote glacier in the world is not easy.

The ice is about -25C (-13F) so the hole is liable to freeze over and the whole process is dependent on the vagaries of the weather.

By early January, the flubber is full and all the equipment is ready but then we get a warning that yet another storm is on its way.

Antarctic storms can be very intense. It is not unusual to have hurricane force winds as well as very low temperatures.

This one is relatively mild for Antarctica but still involves three days of wind gusting up to 50mph. It blows huge drifts of snow into the camp, swamping the equipment, and all the work stops.

We sit in the mess tent playing cards and drinking tea and the scientists discuss why the glacier is retreating so rapidly.

They say what is happening here is down to the complex interplay of climate, weather and ocean currents.

The key is the warm seawater, which originates on the other side of the world.

As the Gulf Stream cools between Greenland and Iceland, the water sinks.

This water is salty, which makes it relatively heavy, but is still a degree or two above freezing.

This heavy salty water is carried by a deep ocean current called the Atlantic conveyor all the way down to the south Atlantic.

Shifting winds

Here it becomes part of the Antarctic Circumpolar Current, flowing deep – a third of a mile (530m) – below a layer of much colder water.

The surface water in Antarctica is very cold, just above -2C degrees, the freezing point of salt water.

The deep warm circumpolar water travels all the way around the continent but has been increasingly encroaching on the icy edge of West Antarctica.

This is where our changing climate comes in.

The scientists say the Pacific Ocean is warming up and that is shifting wind patterns off the coast of West Antarctica, allowing the warm deep water to well up over the continental shelf.

“The deep Antarctic circumpolar water is only a handful of degrees warmer than the water above it – a degree or two above 0C – but that’s warm enough to light this glacier up,” says David Holland, an oceanographer with New York University and one of the lead scientists at the grounding zone camp.

I was supposed to leave Antarctica at the end of December but all the delays mean the drilling only begins on 7 January.

That is when the satellite phone call comes from the United States Antarctic Program HQ in McMurdo.

We are told we cannot delay our flights off the continent any longer and must leave on the supply plane that is due to arrive at the camp in an hour or so.

It is very frustrating to be forced to leave before the hole is finished and the instruments have been deployed, especially given how long it took to get here.

We say our goodbyes and board the plane.

I look back and see the wheel at the top of the drill turning, the black hose spooling out steadily.

They are almost half way down through the ice.

The plane flies up over the camp and directly north, out towards the ocean.

The scientists had told me that we had been camped on what is basically a small bay of ice protected by a horseshoe of raised ground.

As we fly out over the front of the glacier, I realise with a shock just how fragile a fingerhold it is.

There is no mistaking the epic forces at work here, slowly tearing, ripping and shattering the ice.

In some places the great sheet of ice has broken up completely, collapsing into a jumble of massive icebergs which float in drunken chaos.

Elsewhere, there are cliffs of ice, some of which rise up almost a mile from the sea bed.

The front of the glacier is almost 100 miles wide (160km) and is collapsing into the sea at up to two miles (3km) a year.

The scale is staggering and explains why Thwaites is already such an important component of world sea level rise, but I am shocked to discover there is another process that could accelerate its retreat even more.

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Melt rates are increasing

Most glaciers that flow into the sea have what is known as an “ice pump”.

Sea water is salty and dense which makes it heavy. Melt water is fresh and therefore relatively light.

As the glacier melts, the fresh water therefore tends to flow upwards, drawing up the heavier warmer sea water behind it.

When the sea water is cold, this process is very slow, the ice pump usually just melts a few dozen centimetres a year – easily balanced by the new ice created by falling snow.

But warm water transforms the process, according to the scientists.

Evidence from other glaciers shows that if you increase the amount of warm water that is reaching the glacier the ice pump works much faster.

“It can set glaciers on fire,” says Prof Holland, “increasing melt rates by as much as a hundred-fold.”

The small plane takes us to the camp in the middle of the West Antarctic Ice Sheet but more bad weather means more delays and it is nine days before a Hercules comes to take us back to McMurdo.

By then we have been joined by some of the scientists.

It has been a very successful season.

They have confirmed that the deep circumpolar warm water is getting under the glacier and have collected huge amounts of data.

Icefin, the robot submarine, has managed to make five missions, taking a host of measurements in the water beneath the glacier and recording some extraordinary images.

It will take years to process all the information the team has gathered and incorporate the findings into the models that are used to project future sea level rise.

Rising sea levels

Thwaites is not going to vanish overnight – the scientists say it will take decades, possibly more than a century.

But that should not make us complacent.

A metre of sea level rise may not sound much, particularly when you consider that in some places the tide can rise and fall by three or four metres every day.

But sea level has a huge effect on the severity of storm surges, says Prof David Vaughan, the director of science at the British Antarctic Survey.

Take London.

An increase in sea level of 50cm would mean the storm that used to come every thousand years will now come every 100 years.

If you increase that to a metre then that millennial storm is likely to come once a decade.

“When you think about it, we shouldn’t be surprised by any of this,” says Prof Vaughan as we are preparing to board the plane that will take us back to New Zealand and then home.

Ever-increasing carbon dioxide levels are putting a lot more heat into the atmosphere and the oceans.

Heat is energy, and energy drives the weather and ocean currents.

Increase the amount of energy in the system, he says, and inevitably big global processes are going to change.

“They already have in the Arctic,” says Prof Vaughan with a sigh. “What we are seeing here in the Antarctic is just another huge system responding in its own way.”

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By Looking Back Through Hubble Data, Astronomers Have Identified six Massive Stars Before They Exploded as Core-Collapse Supernovae – Universe Today

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The venerable Hubble Space Telescope has given us so much during the history of its service (32 years, 7 months, 6 days, and counting!) Even after all these years, the versatile and sophisticated observatory is still pulling its weight alongside more recent addition, like the James Webb Space Telescope (JWST) and other members of NASA’s Great Observatories family. In addition to how it is still conducting observation campaigns, astronomers and astrophysicists are combing through the volumes of data Hubble accumulated over the years to find even more hidden gems.

A team led by Caltech’s recently made some very interesting finds in the Hubble archives, where they observed the sites of six supernovae to learn more about their progenitor stars. Their observations were part of the Hubble Space Telescope Snapshot program, where astronomers use HST images to chart the life cycle and evolution of stars, galaxies, and other celestial objects. From this, they were able to place constraints on the size, mass, and other key characteristics of the progenitor stars and what they experienced before experiencing core collapse.

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The team was led by Dr. Schuyler D. Van Dyk, a senior research scientist with Caltech’s Infrared Processing and Analysis Center (IPAC). His teammates included researchers from the University of California, Berkeley, the Space Telescope Science Institute, the University of Arizona’s Steward Observatory, the University of Hawai’i’s Institute for Astronomy, and the School of Physics and Astronomy at the University of Minnesota. Their findings were published in a paper titled “The disappearance of six supernova progenitors” that will appear in the Monthly Notices of the Royal Astronomical Society.

The Hubble Ultra Deep Field seen in ultraviolet, visible, and infrared light. Image Credit: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)

As they indicate in their paper, the targets of their study were all nearby core-collapse supernovae (SNe) that Hubble imaged at high spatial resolutions. The images were part of the Hubble Snapshot program, created by the Space Telescope Science Institute (STScI) to provide a large sample of images for various targets. Every target is observed in a single orbit of Hubble around the Earth between other observation programs, allowing a degree of flexibility that is not possible with other observatories.

For their study, Van Dyk and his colleagues examined images of six extragalactic supernovae before and after they exploded – designated SN 2012A, SN 2013ej, SN 2016gkg, SN 2017eaw, SN 2018zd, and SN 2018aoq. With extragalactic targets, astronomers have difficulty knowing if the stars they identified were progenitors to the supernova, given the distance involved. As Van Dyk to Universe Today via email, the only way to be sure is to wait for the supernova to dim, then confirm that the progenitor star has disappeared:

“Since the supernova explosion is so luminous, we have to wait a number of years until it has faded enough that it is less luminous than was the progenitor. In a few of the cases we show in our paper, there is little question that the star that was there pre-explosion is now gone. In the other cases, we’re reasonably sure, but the supernova is still detectable and is just faint enough for us to infer that the progenitor has vanished. “

In a previous study, Van Dyk and several colleagues who were co-authors of this study investigated another supernova (iPTF13bvn) whose progenitor star disappeared. In this case, the research team relied on data obtained by Hubble of the SN site – as part of the Ultraviolet Ultra Deep Field (UVUDF) campaign – roughly 740 days after the star exploded. In 2013, Van Dyk led a study that used images from an earlier Snapshot program to confirm that the progenitor of SN 2011dh in the Whirlpool Galaxy (Messier 51) had disappeared.

The Whirlpool Galaxy (Spiral Galaxy M51, NGC 5194), a classic spiral galaxy located in the Canes Venatici constellation, and its companion NGC 5195. Credit: NASA/ESA

These and other papers over the years have shown that progenitor candidates can be directly identified from pre-explosion images. In this most recent study, Van Dyk and his colleagues observed supernovae in the later stages of their evolution to learn what mechanisms are powering them. In many cases, the mechanism is the decay of radioactive nuclei (in particular, radioactive nickel, cobalt, and iron) that were synthesized by the enormous energy of the explosion. But as he explained, they suspected that other mechanisms might be involved:

“However, we have indications that some supernovae inevitably have additional power sources — one possibility is that the light of the supernova has been scattered by interstellar dust immediate to the explosion, in the form of a ‘light echo’; another more likely possibility is that the shockwave associated with the explosion is interacting with gas that was deposited around the progenitor star by the star itself during the course of the star’s life, in the form of wind or outburst, that is, circumstellar matter. The ejecta from the explosion moving through and interacting with this circumstellar matter can result in luminous energy that can persist for years, even for decades.”

In short, the team was trying to estimate how many of the supernovae they observed evolved through radioactive decay versus more exotic powering mechanisms. Their results showed that SN 2012A, SN 2018zd, and SN 2018aoq had faded to the point where they were no longer detectable in the Hubble Snapshot images, whereas SN 2013ej, SN 2016gkg, and SN 2017eaw had faded just enough. Therefore, they could infer in all six cases that the progenitors had disappeared. However, not all were the result of a single massive star undergoing core collapse.

In the case of SN 2016gkg, the images acquired by Hubble’s Wide Field Camera 3 (WFC3) were of much higher spatial resolution and sensitivity than the images of the host galaxy, previously taken by the now-retired WFC2. This allowed them to theorize that SN 2016gkg was not the result of a single core-collapse supernova but a progenitor star interacting with a neighboring star. Said Van Dyk:

“So, in the old image, the progenitor looked like one “star,” whereas in the new images, we could see that the progenitor had to have been spatially distinct from the neighboring star. Therefore, we were able to obtain a better estimate of the progenitor’s luminosity and color, now uncontaminated by the neighbor, and from that, we were able to make some new inferences about the overall properties of the progenitor, or, in this case, progenitor system, since we characterized the new results using existing models of binary star systems.”

Artist’s impression of a supernova remnant. Credit: ESA/Hubble

Specifically, they determined that the progenitor belonged to the class of “stripped-envelope” supernovae (SESNe), in which the outer hydrogen H-rich envelope of the progenitor star has been significantly or entirely removed. They further estimated that the progenitor was the primary and its companion was likely a main sequence star. They even placed constraints on their respective masses before the explosion (4.6 and 17–20.5 solar masses, respectively).

After consulting images taken around the same time by another Snapshot program, they also noticed something interesting about SN 2017eaw. These images indicated that this supernova was especially luminous in the UV band (an “ultraviolet excess”). By combining these images with their data, Va Dyk and his team speculated that SN 2017eaw had an excess of light in the UV at the time it was observed, which was likely caused by interaction between the supernova shock and the circumstellar medium around that progenitor.

The team also noted that the dust created by a supernova explosion is a complicating factor due to how it cools as it expands outward. This dust, said Van Dyk, can obscure light from distant sources and lead to complications with the observations:

“The caveat here, then, is that the star that we saw pre-explosion might not be the progenitor at all, for instance and — again, because of the distances to the host galaxies — that star is within fractions of a pixel of the actual progenitor (physically, in the immediate neighborhood of the progenitor), such that, if the supernova has made dust, that dust is effectively blanketing both the supernova and that neighboring star. This is possible, but not inordinately likely. And it becomes a harder argument to make in those few cases where nothing is seen at the supernova position years later — as we point out in the paper, that would require enormous amounts of dust, which is likely physically not possible.”

Tracing the origins of supernovae is one of the many ways astronomers can learn more about the life cycle of stars. With improved instruments, data collection, and flexibility, they are able to reveal more about how our Universe evolved and will continue to change over time.

Further Reading: arXiv

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Clamshells Face the Acid Test

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It’s low tide in Bodega Bay, north of San Francisco, California, and Hannah Hensel is squishing through thick mud, on the hunt for clams. The hinged mollusks are everywhere, burrowed into the sediment, filtering seawater to feed on plankton. But Hensel isn’t looking for living bivalves—she’s searching the mudflat for the shells of dead clams.

“I did lose a boot or two,” she recalls. “You can get sunk into it pretty deep.”

Hensel, a doctoral candidate at the University of California, Davis, is studying shells, which are composed of acid-buffering calcium carbonate, as a tool that could one day help shelled species survive in the world’s rapidly acidifying oceans.

The inspiration for Hensel’s research comes from Indigenous sea gardening practices. On beaches from Alaska to Washington State, First Nations and tribal communities built rock-walled terraces in the intertidal zone to bolster populations of shellfish and other invertebrates. Although these sea gardens have not been documented farther south, clams were also vital sustenance in central California. Coast Miwok and Southern Pomo people harvested clams for food and shaped shells into bead money, says Tsim Schneider, an archaeologist at the University of California, Santa Cruz, and a member of the Federated Indians of Graton Rancheria. “So taking care of your clam beds was actually kind of protecting your vault, your bank,” says Schneider.

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In the sea gardens of the Pacific Northwest, caretakers crushed the shells of harvested clams and mixed the fragments back into the beach. Recent research has shown multiple positive effects of this broken shell “hash,” from opening spaces in the sediment so young clams can more easily burrow and grow, to releasing chemical cues that encourage larval clams to settle nearby.

This millennia-old practice may hold the key to addressing a new crisis. As humans burn fossil fuels, oceans are absorbing carbon dioxide from the atmosphere, making seawater more acidic. At lower pH levels, clams and other shellfish struggle to build shells. As their protective structures weaken and dissolve, the animals become vulnerable to damage and predation. But studies suggest that adding shell fragments to clam beds could release carbonate into the water, potentially neutralizing acidity caused by the greenhouse gas.

To find out whether shell hash could help California’s clams survive increasingly acidic conditions, Hensel brought shells from the tidal flat back to the lab, where she crushed them with a mortar and pestle and mixed the fragments into four plastic buckets of sand. Hensel filled these buckets, and four others containing sand alone, with local seawater and added the pinky nail–sized progeny of Pacific littleneck clams collected from Bodega Bay. She bubbled carbon dioxide through the seawater in half of the buckets to increase acidity. With their delicate shells, young clams are thought to be especially vulnerable to acidification.

In the lab, Hannah Hensel bubbles carbon dioxide through the seawater in experimental clam beds to test whether mixing crushed shells into the sediment can protect young Pacific littleneck clams from acidic conditions. Photos courtesy of Hannah Hensel

After 90 days, Hensel dug up all the clams. Comparing the buckets containing more acidic seawater, she observed that the bivalves burrowed in shell hash had grown bigger than the clams in sand alone. Strangely, though, the larger clams were not heavier, and Hensel plans to cross-section the shells to assess whether the new growth was thinner or less dense.

The results inform researchers that shell hash does have a buffering effect under certain conditions, says Leah Bendell, a marine ecologist at Simon Fraser University in British Columbia, who was not involved in the study. “It was a well-done lab experiment.”

Bendell also studies the buffering power of shell hash. Working with the Tsleil-Waututh Nation, Bendell and graduate student Bridget Doyle added shell fragments to clam beds in Burrard Inlet, near Vancouver, British Columbia. In that study, hash reduced pH fluctuations in seawater seeping through the sediment, which can vary markedly with rising and falling tides. Although the reduction was limited to areas with coarse sediments, and the hash did not reduce the overall pH, Bendell sees the results as a hint of something promising. Given a longer period of time, shell hash could have a greater effect on pH in certain clam beds, she says.

Shell hash may not be a panacea for ocean acidification everywhere, but Bendell and Hensel are slowly piecing together how carbonate might help individual beaches weather caustic conditions. Next summer, when Hensel begins adding shell hash to Bodega Bay’s clam beds, she will incorporate another element of traditional sea gardening. Indigenous caretakers regularly tilled clam beds, loosening the sediment and mixing in shell fragments. This repeated digging could bring oxygen to burrowed clams, open more space in the sediments, and alter seawater chemistry, Hensel says, and she plans to measure how the physical process affects both seawater chemistry and clam growth.

Schneider is hopeful that Hensel’s work will improve the health of his community’s clam beds, and the two researchers are discussing ways to involve the Indigenous communities around Bodega Bay. “I think it would just be really rewarding to see community members from my tribe having opportunities to be back out on the landscape to interact with traditional resources in the ways that our ancestors did,” Schneider says.

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Australia begins construction of its section of giant radio telescope

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Construction has got underway in Australia and South Africa of a network of antennas which, when complete, together will form the world’s largest radio telescope, the Square Kilometre Array (SKA).

The giant cross-continental telescope is expected to produce scientific results that will change our understanding of the universe.

Both South Africa and Australia have huge expanses of land in remote areas with little radio disturbance which is ideal for this kind of installation.

The idea for the telescope was first conceived in the early 1990s, but the project was plagued by delays, funding issues, and diplomatic jockeying.

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The SKA is headquartered in the United Kingdom and has 14 members: Britain, Australia, South Africa, Canada, China, France, Germany, India, Italy, New Zealand, Spain, Sweden, Switzerland, and The Netherlands.

The director general of the Square Kilometre Array Organisation, Philip Diamond, has described the beginning of its construction as ‘momentous’ saying it will be ‘one of humanity’s biggest-ever scientific endeavours’.

More than 130,000 Christmas tree-shaped antennas are planned in Western Australia, to be built on the traditional lands of the Wajarri Aboriginal people. In South Africa, the site will feature nearly 200 dishes in the remote Karoo region.

The large distances between the antennas, and their sheer number, mean that the telescope will pick up radio signals with unprecedented sensitivity as the SKA probes targets in the sky.

‘The two complementary telescopes will be the ears on either side of the planet, allowing us to listen to those murmurings from the deep universe which are driving such excitement in both science and deepen our understanding of the universe in which we live and the origins of life,’ says George Freeman, Britain’s Minister of State for Science, Research and Innovation.

Construction of the SKA is due to be completed in 2028.

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