The talented and extremely friendly Dr. Mike DuVernois took to his blog in order to answer some questions for a class of seventh graders. They asked some great questions about neutrinos, life at the Pole, and how you go about creating a giant neutrino detector under the ice.
Do you think we could capture neutrinos and use them for a purpose (like for an energy source?)
We certainly don’t know how to do anything like that at the moment. But it’s an interesting possibility, and many great advances in science and technology were hard to predict ahead of time. Lasers went from being lab curiosities to present in every CD, DVD, blu-ray, and cat toy within thirty years. Nuclear power went from an abstract theory to a commercial source of electrical power in about twenty five years. So in our lifetimes, it’s not impossible that we’d have neutrino energy or neutrino communications.
What type of information are you looking for from your data?
We’re looking to detect these very high energy neutrinos. Lower energy ones from the Sun and from showers/cascades of particles in the atmosphere have been well-measured, but no one has observed neutrinos from astronomical sources. We believe that they must be there, and, in fact, not being able to see them would probably be more revolutionary than seeing them. Our data, in detail, is the time profile (think of a graph of signal intensity versus time) of a very fast pulse in radio waves at a wide range of frequencies. The times of interest are measured in billionths of a second (nanoseconds (cool bit of information, light travels about one foot in one nanosecond)), and the signals are a few times louder (voltage or power) than the random fluctuations that are always present. We’d want to see the signal in a number of different antennas to tell direction and energy of the neutrino that made the pulse.
How do you stay warm? (what do you wear?)
We’re issued some pretty good parkas and cold weather gear. There are some pictures at duvernois.blogspot.com under Extreme Cold Weather (ECW, which is what the gear is called) equipment. Basically you need thermal underwear tops and bottoms, polypro sock liners plus wool socks, insulated pants and a fleece jacket, a balaclava and a hat over that, two layers of gloves, and then ski pants or ski overalls, heavy cold weather boots and a parka. Because it can be so bright, you also need ski goggles. When it gets below about -50F or so, folks working outside typically use chemical heat packs in their boots and gloves. Frost nip and frostbite are occupational hazards here. During the winter season, emergency work is sometimes done outside down below -100F but one can’t be out there for too long.
Do you have running water to shower?
I’m living in the new elevated South Pole Station which is heated and does have running (hot and cold) water. All of the water though has to be melted from snow which takes a lot of energy, so there are strict water conservation rules. You’re limited to two two-minute showers per week and one load of (cold wash) laundry per week. Out at the small camps and bases in Antarctica using snow for daily cleaning is normal, and the only hot water is from a small pot on a stove. Folks are relative grimy here overall.
Has anyone ever been injured while working on project icecube?
There have never been any serious injuries on IceCube, though there have been a few close calls. Those have mostly been with the heavy equipment and cranes operating overhead. IceCube has a fairly extensive (many hundreds of pages) safety manual and most of the work done here is, more or less, in accord with US style safety regulations. Minor injuries are relatively common, it is both extremely cold and dry which means that it’s very easy to have bleeding cuts and scrapes that are typical with any mechanical work. Additionally there are the cases of frost nip, especially at the beginning of the summer season when it’s still warming up. There are many tales, some of them even true, around the Antarctic program of terrible accidents at various times and places. There are wrecked aircraft on the ends of several of the runways down here.
How did they drill the holes?
What do you do if your equipment breaks down?Both the IceCube and ARA holes are drilled with hot water. Essentially there is a big tub of hot water, and a long pair of hose (one inlet and one outlet) and the necessary pumps and heaters. Hot water is pumped through the hose into the snow, and water is pumped back to be reheated. The hose is let out slowly and it sinks down into the ice. It takes about two days (working 24 hour per day) to drill down 1 1/2 miles in the ice. The resulting hole is about 14-18″ in diameter (with this drill setup, you could make it wider by slowing down the advance of the hose or increasing the flow of water), filled with water, and 12″ diameter modules are lowered into the hole. The warm water in that hole takes up to a week to refreeze solid at which point the electronics are there to stay.
The folks who built the drill are here at Pole operating it, so they can work on any problems with it. In general, there is a lot of ability floating around here, any bulldozer, snowmobile, washing machine, radio transmitter, or aircraft here in the field has to be able to be repaired in the field. Some problems might require parts to be shipped in or the use of spares rather than repairs.
How is the equipment powered?
The station heat and electricity comes from diesel. The vehicles on the ground here are powered with either diesel or gasoline. Electricity is generated where required with small electrical generators which are also either gas or diesel. McMurdo used to have a nuclear reactor, and they have some new wind turbines. At the South Pole there is huge interest, both environment (we burn a lot of fuel in the middle of a pretty pristine place) and logistics (all of that fuel is flown down to the Pole on airplanes with the exception of a small amount which arrives on a land traverse, picture a convoy of big tracked dozers pulling sleds with fuel bladders on them), in making more green power. The problems though are difficult (otherwise it would already have been done!), sunlight only 1/2 of the year plus clearing the snow off of the solar panels, it’s windy in the summer, but often windless in the winter…
Do you need a certain certification to be part of project icecube?
How were you chosen to be part of the research project?The IceCube folks are basically of three backgrounds: science, these are almost all Ph.D. physicists (as experimentalists we work on the instruments as well as the science, so picture a lab of electronics and sensors rather than formulas on a blackboard); technical, we have a couple of project management folks and engineers, typically they have spent much or all of their careers working closely with scientists; and drillers, these are folks hired in to work on the drilling, they have a WIDE variety of backgrounds and when they aren’t drilling for IceCube they might be on the north slope in Alaska, or on a rig in the north sea, or putting in deep wells in Saudi Arabia. There are always exceptions, especially in the whole Antarctic end of things. The gal who runs the communications facility at the South Pole Station was our camp manager many years ago in McMurdo on a balloon campaign. Folks with the US Antarctic Program jobs tend to keep showing up around the continent that they love
IceCube blog
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