An icy mystery deep in Arctic Canada
Known as the "Crystal Eye" to the Inuit, Pingualuit Crater was once the destination for diamond-seeking prospectors. But the real treasure is the stories its deep waters can tell.
The plane banked to the right, hard. As we took a first sweep at the runway – or, rather, the short stretch of bumpy land in the Arctic tundra that would serve as one – an alarm sounded, the lights above the emergency exits flashhed red and the sound of the aircraft's engines roaring back into action filled the main cabin. My stomach lurched.
It was an exhilarating introduction to the far north of Quebec, in a region known as Nunavik. Comprising the top third of Canadian province (larger than the US state of California and twice the size of Great Britain) fringed by frayed edges of a peninsula known as Ungava, most people don't even know it exists. But that wasn't always the case.
Back in 1950, this area was splashed across newspapers globally and pegged as the eighth wonder of the world. Not because of the wilderness, and not due to any manmade structure, but because of the distinct land feature I was now flying over enroute to take another shot at the runway: Pingualuit Crater.
"The name is Inuktitut for the skin blemishes or pimples caused by the very cold weather," explained Isabelle Dubois, project coordinator for Nunavik Tourism, who had previously only visited the crater in winter when the landscape was covered with snow.
I looked out of the window to distract myself from our second landing attempt and thought how apt a moniker it was. The tundra here is pockmarked by clefts, fissures and depressions filled with tiny pockets of water. Yet amid the myriad indentations, the eponymous crater stood out significantly
With a diameter of nearly 3.5km and a circumference well over 10km, it wasn't only its size that distinguished it, but also its symmetry. Almost perfectly circular and filled with water, the crater seemed as though a giant had discarded a compact mirror on the ground, which our tiny Twin Otter aircraft was now reflected in, appearing as no more than a tiny speck of dust.
With a few bumps, more warning alarms and a sudden and dramatic halt, we landed, just a couple of kilometres from the edge of this curio. We would stay at Manarsulik camp, a cluster of five solar-powered cabins and the official base camp of anyone venturing into Pingualuit National Park, one of the remotest national parks in the country.
As we unpacked the plane (there are no porters or staff here) and set ourselves up inside the warm cabins, I chatted with Pierre Philie, a French cultural geographer with a strong interest in anthropology and resident of Kangiqsujuaq (Nunavik's most northern settlement and gateway to this geographical wonder). He was sent begrudgingly on assignment to this part of Quebec 40 years ago, fell in love with it and a local woman, and never left.
Philie showed me a copy of a black and white aerial photograph of Pingualuit. It was taken on 20 June 1943 by one of the US Army Air Force officers who spotted it. As I wondered what the officer must have made of it back then, Philie began to explain a little more about the crater.
"It was first known to anyone from the Western world that year, during World War Two, when fighter pilots spotted it and used it as a navigational aid. But they didn't share it with the rest of the world until the war was over," he said.
When they did, in 1950, one of the first people to be mesmerised by it was a prospector from Ontario called Fred W Chubb. He was convinced the landmark was caused by a volcano, which would likely mean diamonds lay within it. He asked the advice of the then-director of the Ontario Museum, Dr Meen, who, equally captivated, journeyed there with him to investigate (it's the reason that for a short time Pingualuit was known as Chubb Crater) – but the volcano theory was eventually dismissed.
"Now we know beyond doubt that it is a meteor crater," said Philie, as the sun began to set over Manarsulik Lake, located about 2.5km from Pingualuit, leaving the edge of the crater as faint as a watermark on the dazzling pink horizon. "Tomorrow we shall see it."
The next day began at sunrise with a stroll among great shards of rocky clitter. Some, Philie explained, were large chunks of granite and broken bedrock (relics from glaciation during the last Ice Age); others were examples of impactite, formed as a result of melting during impact. The latter were ink black and covered with tiny holes, evidence from when the minerals within liquified and bubbled during the heat and pressure of the collision.
Its impact is estimated to have been 8,500 times stronger than the A-bomb dropped on Hiroshima
"The impact happened 1.4 million years ago," confirmed Philie, as we ascended the lip of the rim. "Looking at the crater's width and depth [around 400m], its impact is estimated to have been 8,500 times stronger than the A-bomb dropped on Hiroshima."
That fact was remarkable. But finally reaching the edge and gazing down on the gaping hole of Pingualuit, where the lake inside sparkled with ice that encrusted two thirds of it – despite it being July – was even more astounding.
"Of course, the Inuit knew about it before the Westerners came to look for diamonds," said Markusie Qisiiq, Pingualuit Park director and guide. "They called it the Crystal Eye of Nunavik."
From where I stood, under an impossibly blue sky dotted with as many clouds as the tundra was with "blemishes", that name seemed to fit best of all.
As we made our way over the rough ground, circling the lake, Philie became increasingly animated. He spoke about the clarity of the water inside – which is fed only by rain and thought to be the second purest water in the world (only more transparent is Lake Mashu in Japan); about the mystery of the Arctic char that live within it – which scientists still can't agree on how they got there as there's no streams running in or out, and who have turned to cannibalism to ensure their own survival; and about evidence that shows that as well as the Inuit, another people roamed here too at least 1,000 years before them.
"The landscape is a living book," he concluded. "There is so much we can learn if we take the time to read it."
In recent years people have been coming to do just that.
In 2007, a team of researchers from Laval University in Quebec, led by Professor Reinhard Pienitz, visited in winter to take samples from beneath the water. Pienitz described it then as a "scientific time capsule" and one that, even as they continue to learn more about it, can reveal clues about past episodes of climate change and how ecosystems adapted under pressure.
I walked to the water's edge, where Philie picked up a rock and tossed it onto the frozen surface. The otherwise silent air was immediately filled with a melodious chime as splinters of ice ricocheted against each other and drifted off into the water.
After filling our bottles to taste this pure H2O, we made our way back to camp. We only stopped once, forced to by the passing of an almighty caribou herd in numbers too large to count. As I watched this migrating wildlife spectacle alongside a crater as large as one found on the Moon, my stomach lurched once more.
But this time it wasn't caused by a bumpy landing. Instead, it was the realisation that while there may be no diamonds here, there is a wealth of stories and scientific revelations just waiting to be discovered, mere metres beneath the surface.
Maskelyne thus elected to personally oversee the work that would eventually give Schiehallion something akin to celebrity status in the hiking world, as evidenced by the 20,000 hikers who visit each year. They each pass a commemorative cairn, celebrating the work of Maskelyne and his team, in the Braes of Foss carpark at the start of the hike.
Not long into my own ascent of Schiehallion, I saw my first fellow hiker trudging down a well-trodden path, looking somewhat dishevelled. Early autumn had rebranded the bracken-laced slopes in a burnt sienna, while above me there was only cloud and, presumably, the rest of the mountain. Already though, with no large mountains nearby, the view from the lower slopes exposed vast tracts of central Scotland.
As the hiker neared me, I recognised an eager exhaustion in him. "I did it," he said. "My first Munro," referencing the 282 mountains across Scotland whose peaks lie above 3,000ft. With the carpark in sight, he was eager to get off the mountain. "I'm glad it's over," he said. His shellshocked-looking springer spaniel followed after him, barely stopping to sniff my boot.
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Gravity never seems quite as strong as when you're hiking uphill. In only a few minutes, I felt that sweet pull of the mountain drawing me in. Before long, the ground in front of me was all I saw; a morass of stone and hardy grasses, leading me on until we fell together like weary heavyweight boxers whenever I stopped for a water break.
Sir Isaac Newton was the first to determine that everything has its own gravitational force. He also believed that gravity was too weak to measure at anything lower than a planetary level. But without having a measurement of Earth's gravity, it would be impossible to calculate its weight, because gravity is variable. For example, if I stood on a bathroom scale on Earth, I'd weigh more than on the same set of scales on Mercury, a smaller planet than Earth with a lower gravitational force, even though my mass would remain the same.
What Maskelyne and other scientists of his time had realised was that if you could get close enough to its centre of mass, a mountain's gravity might be actually strong enough to measure. That meant finding a mountain with steep slopes. But if one mountain has a gravitational pull, so do all the others, potentially distorting the measurements. For this reason, Schiehallion, which was located far from other similarly sized mountains, was the perfect fit.
A commemorative cairn at the start of the hike celebrates the work of Maskelyne and his team (Credit: Stan Pritchard/Alamy)
Maskelyne requested that observation stations be built on Schiehallion's steep north and south slopes, at points closest to the mountain's centre of mass. From here, a pendulum was hung, pulled towards the centre of the Earth by our planet's own, superior gravitational force. Crucially, Maskelyne needed to prove that Schiehallion's gravity was drawing the bob of the pendulum away from its vertical position.
Maskelyne did this by tracking the transit of 43 different stars from each observation station to triangulate what is known as "true vertical", ie, the angle of the pendulum, had it been suspended on a flat plain, affected only by the Earth's gravitational pull and nothing else. He discovered that from each observation station on either side of the mountain, there was a clear deviation of the pendulum away from true vertical, towards the mountain.
Schiehallion's gravitational pull was thus proven, but the work was just getting started. Next, the whole mountain was to be surveyed in order to calculate its volume, a task that fell to the team of mathematician Charles Hutton.
Inclement weather is certainly no stranger to Schiehallion; it took Hutton's team almost two years to fully map the mountain because of it. As I reached the ridgetop, the clouds descended further, blotting everything out. Soon, the well-marked path disappeared into a challenging boulder field. Only the odd mist-obscured cairn indicated the way.
A spectral couple appeared through the gloom and told me that the peak was not too far off. Ten minutes later, the route I was on seemed to be heading downhill. But worse, the cairns had disappeared and the path was angling round towards the sheer north face. I found it difficult to tell whether the boulder I stood on was overhanging the abyss or just more stone, so I stopped to pull out my map and compass.
When Hutton finished surveying the mountain, he had a map covered in thousands of precise longitudinal and elevation readings. In school we learn to compute a cube's volume by multiplying its length, width and height. But real life doesn't give us straight lines; it gives us curves, aberrations, knolls and fissures. These were exactly what Hutton's measurements showed.
They were proving a little tricker to compute, and calculating the volume of the whole mountain seemed virtually impossible. Then Hutton had the ingenious idea of dividing the mountain up by bunching values at similar altitudes together. Taking a pencil, he connected those altitude points together, forming a series of imperfect rings. Inadvertently, he had just invented contour lines, which, to this day, remain one of the most valuable pieces of information on a map.
As I suspected, I was lost. After the correct path descended slightly from one of Schiehallion's many false peaks, I'd taken a wrong turn. My map showed densely packed contour lines right about where I judged myself to be standing, which meant it was about to get very steep, very soon. I abruptly retraced my steps, thanking Hutton and his contour lines for quite possibly saving me from falling over a cliff edge.
In 1775, Maskelyne presented the final results to the Royal Society. We now know that the estimations of Maskelyne and his team were within 20% of what the Earth is now thought to have a mass of (5.97 x 10^24kg, in case you were wondering), a significant improvement on previous estimates at the time. Maskelyne and Hutton's measurements were used as recently as 2007 to obtain a closer estimate of the Earth's mass.
Scientific discovery is not unlike hiking up a cold, damp, cloudy mountainside. But this 18th-Century feat cleared a great deal of mist for future astronomers and physicists, not to mention the many hikers who attempt to reach the peak of Schiehallion every day in homage to this geological marvel's contribution to our understanding of the cosmos. And thanks to those experiments, those ingenious contour lines will always give us a sense of a mountain's shape, even when our eyes cannot.