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Lake Ellsworth Project Returns To Life After New Component Delivered

December 22, 2012
Image Caption: Lake Ellsworth, Antarctica ice drilling site. Credit: British Antarctic Survey

[Watch Video: Tractor Train From Union Glacier To Lake Ellsworth]

Lawrence LeBlond for redOrbit.com – Your Universe Online

Update (Dec. 22, 2012)

A long-awaited project to drill through Antarctica´s ice sheet to a deep subglacial lake to look for life has been on hold for the past week due to a malfunction in the drill´s boiler system. The team heading the $12 million operation could only sit patiently in the subzero temperatures of the southern continent as they waited for a new part to arrive.

The part, a tiny electronic component no bigger than a microchip, arrived Friday after a 9,000-mile journey from Chile. With the new part now in their grasp, the British Antarctic Survey (BAS) team members will try to restore order to the drilling machine and return to the hunt for life and the mysteries of the deep. The team hopes to restart drilling next week.

The drill must be powered by hot water to be able to cut through the thick southern ice sheet, but had to be shut down when the variable resistor on the boiler´s circuit burned out. The team replaced the component with a stand-in, but that part also failed.

Tension has been mounting for the BAS team due to uncertainty about whether the boiler will not only fire up but also whether it will be able to keep the machine running for at least a week. Another concern for the crew is the amount of fuel being used to run the back-up boiler which is crucial for maintaining the drill system from freezing in the blistering cold clime.

The researchers said as long as the back-up boiler is being run to keep the system warm, precious fuel is being used up, making a successful drilling process less likely every day. The main boiler is needed to power the drill, and without fuel, the project is a dead stick. And the team is not sure how much longer the weather will cooperate. Earlier forecasts called for a week of low winds and partial cloud cover. But with temperatures hovering in the -20s, any wind chills further complicates matters.

The BAS said if this replacement fails, another replacement is already en route from Britain but is likely to take several days to reach the site. As winter nears on the southern continent, the window for opportunity is shrinking fast for this year´s drill efforts. If the weather becomes an issue, the team said they will most likely winterize the equipment and return next year for another attempt.

But sources at the BAS told the BBC “fingers are crossed” that this new component will not fail. If the drilling does restart next week and goes off without a hitch, the first samples could surface within a week.

Update 1 (Dec. 17, 2012)

A British expedition to search for life under the Antarctic ice sheet has hit a snag.

The British Antarctic Survey reported a “serious problem” with the main boiler used to heat the water to power the drill. Work was stopped on Saturday as the team struggled to determine what went wrong with the machine, many worrying the 16-year planned mission to drill to Lake Ellsworth below the ice sheet could abruptly come to an end.

The team´s goal is to use 194 degree F water to blast a hole through nearly two miles of ice to the lake below to search for signs of life and study the history of the continent´s subglacial past and aquatic history.

“The technical difficulties are something that are not unfamiliar in Antarctica – it’s a hostile environment and very difficult to do things smoothly,” said Professor Martin Siegert, chief scientist on the project. “The good news is that we found the fault relatively early on in our deployment system and so we have quite a lot of fuel that is left remaining. If we didn’t have that of course we wouldn’t be able to continue any further.”

The project relies on the successful operation of the hot water drill, which in turn relies on the boiler. Without that, the project is a dead stick. The team initially reported Thursday a key circuit on the boiler failed to start. A back-up burner was fitted and ran successfully until Saturday.

The team said a replacement component has been ordered and is expected to arrive in a few days´ time.

For the time being, “the engineering team is in contact with the manufacturers of the units who are helping them to determine the cause of the malfunction,” according to a statement from the drilling team. “Both units demonstrated the same problem. When the replacement circuit arrives the engineers will work with the manufacturer to go through the set up procedure. The team is hopeful that this will solve the problem.”

If the replacement part does not fix the problem, the team may bypass the circuit altogether and “manually drive the burner.” Before the team decides on this measure, they want to explore all possible options with the manufacturer first, according to the statement.

Project Manager Chris Hill told BBC News by email the boiler was running on a back-up electric element which is not powerful enough to heat the water to the temperatures needed to drill through the ice.

“We are also vulnerable if this element fails, we will have to fully drain down the system“¦and start over from scratch – this would be a big deal,” he said.

There were also concerns the pipes would freeze, potentially ending all chances to resume drilling, but sources at the BAS said there was no issue with water freezing in the pipes. They said the system is still “ticking over” with warm water.

“We’re working very hard to make sure things are right here. It’s not the end of the field season by any means and with our suppliers in the UK and the expertise we have on site we’re hopeful to restart drilling in a few days’ time,” Siegert said.

The team knew there would be high risks with this project, and were as best prepared as could be. But it is unlikely the team will resume drilling before December 21, according to sources.

Main Story (Dec. 12, 2012)

A British team of researchers is about to drill for life in Antarctica. It is a project that has been in the making for more than 15 years and is now becoming a reality for 12 scientists and engineers who want to explore an ancient lake deep below the Antarctic ice sheet. But getting there requires drilling through 2 miles of ice.

The site, Lake Ellsworth, was discovered in 1996 by British scientist Martin Siegert, who is part of the current mission. The lake is one of 387 known subglacial bodies of water in Antarctica and experts believe it is the best candidate for the search for microbial life. Finding life in these dark, nutrient-poor, atmosphere-deprived waters would be significant, as scientists have speculated any life that has evolved here would have been isolated for the last half-million years.

The drilling, which starts today, is a delicate process. The $12-million operation utilizes nearly 100 tons of equipment, including a high-pressure hose with sterilized water near boiling point to blast through more than two miles of ice. Initial drilling will be done in short bursts as they test out the equipment.

Chris Hill, program manager at the British Antarctic Survey for the project said the team hopes to reach the lake by Sunday.

“Since that boiler fired up, the mood´s been pretty good,” Hill said in a satellite phone interview with Bloomberg. “We have to wait on this like expectant fathers.”

Siegert explained the initial process will be to open a bore-hole, which will take about five days. Following that process, the crew plans to start a rapid sampling operation before the ice refreezes. He told the BBC´s David Shukman that “everything has to be done in ultra clean conditions.”

“We don’t want to contaminate this pristine environment – and unless we keep the experiment very clean, we’re likely just to measure the things that we bring down us with, which would be pointless,” he added.

The goal of the mission is to recover water and sediment samples from the lake to determine if life exists there and also to offer clues on the continent´s climate history in ancient times.

“The most likely organisms to be found will be bacterial – - they´re everywhere,” David Pearce, a microbiologist at the program said in an October interview, shortly before heading to the southern continent to begin preparations. “If there´s nothing there, that will tell us the limits for the existence of life on Earth.”

Andy Tait, the engineer in charge of the drilling process, also described the operation as “delicate.” He explained while the technology of hot-water drilling “has been used extensively by scientists in the past, this is the first time we’ve ever attempted to go through [2 miles] of solid ice – this will be the deepest borehole ever made this way.”

Tait said the boilers are fired up to around 194 degrees F and water pressure comes out of the hose at around 2,000 PSI–or about 15 to 20 times more powerful than the pressure found in car wash hoses.

After initial drill tests, the team will bore down about 1,000 feet and create a water-filled cavity to help balance the water pressure between the lake and the hole. Then, they will start a new hole from the top and bore down to the cavity and then on down to the lake.

Once the holes are drilled, the process gets tricky. Hill said researchers have a relatively short window of 24 to 30 hours to recover samples before the hole freezes and becomes too narrow to safely lower and then remove instruments.

After drilling, the first instrument to be lowered into the hole will be a sterile ultraviolet lamp to irradiate any life around the edges of the hole, said Hill during the October mission briefing. The second instrument to be lowered will be a probe with canisters that will collect water samples from different depths. Finally, a sediment corer will be lowered down to recover sediment from the lake bed. Scientists hope by getting sediments from the lake bed, they will be able to tell whether the ice sheet has retreated in the past, which could be indicative if they find any fossilized organisms deeper in the silt.

Siegert said exploring for life in such an extreme environment–in pitch-black conditions under high pressure beneath the ice sheet–could open up possibilities for life in other extreme environments, such as Jupiter´s moon Europa.

“The experiment we’re doing is very similar to an experiment one might do to see whether there is life on Europa,” explained Siegert in the BBC interview. “We know Europa has an icy crust and an ocean beneath it. If there’s life on Europa it’ll be living in a very similar way to life in Lake Ellsworth with total darkness, lots of pressure and using chemical processes rather than sunlight to power biological processes.”

Hill said researchers will be able to study the samples nearly as soon as they are returned from the deep. Other samples will be shipped back to mainland UK, where they will be further scrutinized by laboratories around the country. He said the first scientific papers on their findings could be published by late 2013 or early 2014.

If everything goes smoothly and the conditions are manageable, Hill told Bloomberg the team will re-drill and lower a second set of instruments down for more samples. Hill said the five-day forecast predicts low winds and some cloud cover. The Antarctic summer usually sees temperatures hovering around 0 degrees F during the day, with night-time temps dipping to -35 degrees with a wind chill.

The project, 16 years in the making, would likely not have surfaced if it weren´t for radio echo-sounding data compiled by Siegert in the 1990s. Siegert, a glaciologist at the University of Edinburgh, was the first to uncover Antarctic´s lakes through his research. Lake Ellsworth, which Siegert discovered in 1996, was first identified as a potential target for exploration around 2004.

The multi-million-dollar project is being funded by a consortium of UK universities.

A Russian team became the first to drill the ice sheet for life back in February. They drilled through more than 2 miles of ice to reach the water of Lake Vostok. That group collected samples of “fresh frozen” water, according to the country´s Arctic and Antarctic Research Institute. No findings have been published on that project as of yet.


Source: Lawrence LeBlond for redOrbit.com - Your Universe Online



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