Antarctica Articles 1998 - 1999

Scientists hunt key to alien life 4 kilometres beneath Antarctic

Ottawa Citizen Online - July 9, 1999

Two groups of scientists whose worksites are located as far apart as Antarctica and Jupiter's moon Europa are developing a joint research project to examine a huge freshwater lake beneath Antarctica's ice sheet. They hope to find early life forms in both places.

The Antarctic lake -- the largest known in the frozen continent -- is almost as large as Lake Ontario, and twice as deep. Sandwiched between the continent's bedrock and the overlying ice sheet, it lies partly beneath Vostok Station, established by the Soviet Union in 1957. The desolate station was known as the coldest outpost of the Cold War.

A strange reflection in a single seismic record through the ice sheet in 1964 was first interpreted by scientists as a reflection from loose deposits under the ice. During the 1970s, radio-echo soundings showed the area to be large and flat, and the soundings were correctly interpreted as a sub-glacial lake. By 1994, the presence of a lake had been confirmed beyond reasonable doubt.

When scientists at NASA's Jet Propulsion Laboratory heard about the lake, they became intrigued because the surface of Europa is believed to be ice -- beneath which there could be water.

The notion that liquid water might be trapped below the ice of one of the moons of Jupiter was the basis for Arthur C. Clarke's 1984 science-fiction novel 2010: Odyssey Two.

NASA proposed using Lake Vostok as an experimental test site. But at this point, biologists intervened because they feared drilling through the four-kilometre ice layer would lead to contamination of the ancient waters beneath. The ice has sealed the water off from the outer world for at least one million years.

Peter Clarkson, executive secretary of the Scientific Committee on Antarctic Research at the Scott Polar Research Institute in Cambridge, England, which is coordinating the venture, says Lake Vostok "represents one of the most exciting multidisciplinary research opportunities in Antarctica today. ... The potential gains for both Antarctic and planetary science, by successfully sampling the lake and the sediment using contamination-free methods, are enormous."

Sampling the water could reveal micro-organisms in lake sediments, since Lake Vostok is presumed to have been biologically active before glaciation occurred millions of years ago. Elsewhere on ocean floors, previously unknown life forms have been found around volcanic vents. Similar conditions might be present both in Lake Vostok and on Europa.

Scientists seek to answer a question that has critical implications for the existence of life elsewhere in the universe: can life actually originate under these conditions?

Both the planetary and Antarctic projects require similar technical developments: an ice-probing vehicle, or Cryobot, miniature instruments for measuring chemical concentrations, and an oceanic robotic submersible, or Hydrobot, and its communication system.

The Cryobot is likely to be a version of the Philberth probe used in terrestrial ice since the 1960s. Heated by hot water, the probe melts through the ice, while its path is sealed behind it as new ice forms. (On Europa, the probe would be heated by radioisotope thermal generators, rather than hot water.) Once the Cryobot got through the ice into the water below, it would release the Hydrobot, which could take continuous measurements, possibly for years.

Despite difficulties, if funding can be obtained from NSF and NASA, along with what Dr. Ellis-Evans has obtained from the European Science Foundation for the next workshop, he says "we'd stand a chance of getting into the lake within the next five years.

"It's going to be a major undertaking. When you're working at minus-30 and minus-40-degree air temperatures, it's quite an exercise."

Canada has no direct involvement in the project, but Canadian scientists are doing Antarctic research, including Ottawa's Olav Loken, who is Canada's delegate to the Scientific Committee on Antarctic Research. It's even possible the Canadian Arctic might serve as a test site, according to Dr. Carsey: "One place we're thinking of is the Ward-Hunt ice shelf. It sits on fresh water which has very salty water underneath. We need places to try things out, and it's pricey to go to Antarctica."


Antarctica Gives Clues To 'Lost' Supernova

September 16, 1999 - Reuters - London

Evidence of a ``lost'' supernova that exploded some 700 years ago has turned up in the snows of Antarctica, New Scientist magazine said Wednesday.

X-rays from the German-US orbiting Rosat satellite have shown a glowing supernova remnant just 640 light years away, suggesting the star's explosion lit up our skies at the beginning of the fourteenth century, making it by far the closest supernova in our past.

But unlike other supernovas which astronomers recorded, scientists found no historical reference to this event.

Then 20 years ago, analysis of an ice core in the South Pole showed four concentrations of nitrates in the snow. Dating revealed that three of them coincided with bright supernova explosions in 1181, 1572 and 1604, which were all recorded.

Now scientists say the fourth ``spike'' or concentration is the sign of the explosion pinpointed by Rosat.

Its depth in the ice core corresponds to a date of around 1320, very close to the date roughly estimated from Rosat observations using theories of how supernova remnants evolve.

"This fourth spike corresponds precisely with the time when light...from the recently discovered supernova would have been arriving at the Earth,'' said Kai Zuber of Dortmund University, who, along with Clifford Burgess of Montreal's McGill University, has reached the new conclusions from the evidence.

The evidence from the ice core points to what astronomers call a type II supernova -- the obliteration of a colossal star 15 times as heavy as the sun.


Fossils Show Dinosaurs Roamed A Warmer Antarctica

July 13, 1999 - Reuters - Wellington

Geologists have discovered the fossilized remains of massive dinosaurs in Antarctica, signs that many prehistoric "eating machines" were spread over a much broader territory than previously believed.

An expedition to the remote Antarctica Peninsula and nearby islands has unearthed large deposits of dinosaur fossils, including remains of two types of large marine reptile -- mosasaurs and plesiosaurus.

The leader of the expedition which unearthed them in January, Dr Jim Martin from the Museum of Geology in South Dakota, presented the group's findings at a symposium on Antarctica Earth Sciences in Wellington this week.

Martin said the big surprises had been the concentration of remains found as well as evidence of great diversity of species and a much warmer climate in the polar region.

The number of mosasaurs was especially striking. "Mosasaurs were just fantastic animals, some of them were up to 10 meters long, maybe more, they were armed with teeth that were three or four inches long. The skulls would easily be a meter long. "They were eating machines, that were designed to eat anything and they did."

To have revealed remains of at least four different species among the complete vertebrae, partial skeletons, whole jaws and teeth in the find was unexpected in such a remote locality.

"To find a whole bunch of them like this is really surprising. We were expecting to find maybe one little bone fragment, but here were at least four different kinds of mosasaurs," he said.

One type, Plioplatecarpus, is believed to have been adapted to relatively shallow water and its discovery in Antarctica suggests the continental masses were once much closer, with connecting marine corridors.

"We also found a duck-billed dinosaur known as a hadrosaur on Vega Island. This was even more of a surprise.

"We had always thought of them as a North American dinosaur. This suggests that North America, South America and Antarctica were connected at the end of the Age of Dinosaurs."

Martin said the creatures probably came to Antarctica in the late Cretaceous period, some 75 to 80 million years ago.

He said his colleagues on the expedition, Judd Case and Mike Woodburne, had hypothesized that marsupials now found in Australia actually got there from North America by travelling the length of South America, across Antarctica, and into Australia before the continents split up.


Antarctica - Awesome Iceberg Impacts

BBC Online - April 16, 1999

Icebergs crashing against the sea floor could be the most devastating natural disaster that any living community on Earth experiences.

Scientists from the British Antarctic Survey have discovered that over 99.5% of all visible sea-bed dwellers are massacred when the bergs collide with the ocean bottom.

Floods, earthquakes and even meteorite impacts cannot claim such total destruction. The project leader, Professor Lloyd Peck, told BBC News Online: "In biological terms it is outrageous - it's almost a sterile environment."

Up to 20% of the world's oceans are prone to catastrophic ice berg impacts. Even ocean floor as deep as 500m is at risk.

The bergs float in and gouge and trample the communities as they rock back and forth in the tide. It is their immense weight that causes the damage.

"The biggest icebergs are the size of Oxfordshire and weigh two billion tonnes. The impact force is greater than that of cruise missiles - it's immense," says Professor Peck.

His team, including colleagues from Gent University, Belgium, set up three underwater test sites near Signy Island, Antarctica. All were destroyed within 18 months.

They dived beneath the sea and used vacuum pumps to suck up the animals living on the sea bed both before and immediately after the berg impact.

They were shocked by the totality of the death toll. In some cases, literally everything had been ground to a fine powder.

"For animals bigger than one millimetre, there were eight really common groups and six disappeared completely," explained Professor Peck. "The removal of the other two species was over 99.5%.

"Animals smaller than one millimetre, like nematodes, went down from two million per square metre to a few hundred."

Rising from the ashes

For the first time, the scientists also tracked the recovery of the obliterated sites. It had been thought this would take years.

But the first arrivals re-colonised within a few days, simply by walking back in. The smaller creatures needed the assistance of a major storm to be swept back in. This occurred within four months, with a 150 km/h gale.

And this revealed a surprise - the berg impacts actually revitalise the sea floor communities in the same way that forest fires clear "dead wood" and allow new trees to flourish.

"The icebergs actually help to maintain the population with a larger number of young animals because it's clearing areas for settlement," says Professor Peck. "So the ice bergs do have positive effects as well."


What Antarctica is Like

Reuters--February 1999

Antarctica is the coldest and perhaps loneliest place on Earth, whose residents inhabit a surreal setting.

From October to March the sun never sets on the frozen Antarctic wastes, while in winter it never rises.

During the daylit summer months, the continent -- the size of the United States and Mexico combined -- boasts a population of just 4,000 to 5,000 people.

In the dark winter, temperatures plunge and the icy landmass is home to just a few hundred isolated hardy souls.

Most of the residents of Scott Base and the nearby U.S. facility of McMurdo Station are men but there are increasing numbers of women.

Mactown, as McMurdo is known, is a sprawling mass of ugly brownish blocks, supply dumps and pipelines. More than 1,000 people live here. There are three bars and one chapel.

It is less than an hour's walk from the smaller Scott Base over a steep hill or, weather permitting, across sea ice in McMurdo Sound. Drink prices in Mactown's bars are higher but Scott's people make regular pilgrimages nonetheless.

In the winter there are no supply drops or flights, though telephones and e-mail provide links to the outside world. But this is a curse for some.

"That distant voice down the line can actually make things worse, Sometimes I wish there was no way of finding out bad news from home," said one veteran of seven Antarctic winters.

Antarctica has no government and no capital. Some 43 nations are signatories to the 1959 Antarctic Treaty, which pledges peaceful, non-commercial use of the frigid landmass.

With no indigenous population, the only people are at around 40 scientific research bases maintained by treaty countries, where stringent environmental protection protocols are observed.

All trash is separated -- plastics, paper and other goods for recycling; items that can be safely incinerated; toxic chemicals and waste to be shipped off for disposal in other countries.

If a scientist or polar explorer finds nature calling, jumping behind a boulder or ice mound for relief is not an option.

Eric Philips, who accompanied Everest conqueror Edmund Hillary's son Peter and one other man on a recent 84-day trek to the South Pole, said they left nothing behind as they slogged through the unending icy wilderness. "In the morning we'd get up out of our sleeping bags, tear open our breakfast rations and then use the bags for morning relief," he said.

The three men carried all their feces on the 846-mile trip. "Nothing is put into the environment here," said Dr. Roberta Marinelli, at a remote site called Lake Hoare where the United States is conducting long-term ecological research. "If you need to go to the bathroom, please do not go behind a rock as the nitrogen shock to the environment could be the worst for thousands of years."

The bone-dry Antarctic air also causes problems. Bare metal poles are positioned throughout the base and computer workstations have metal strips along desk edges. The reason? Static electricity.

Everyone becomes a highly charged ball of static. Loud cracks can be heard as people discharge themselves on metal as they walk around the base or before touching any electrical equipment. "You must discharge yourself. Computers and other gear are likely to be badly zapped if you don't," said Mike Mahon, a base scientific technician.

People wake in the morning with blinding headaches and dry mouths due to dehydration after moisture has been sucked from their bodies by the desert-like air as they sleep.



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