By Tom Still
John Wiley, the former UW-Madison chancellor, is a physicist by training, and accustomed to his profession’s penchant to undersell its accomplishments to any audience – except other physicists.
So when Dr. Michael DuVernois described the IceCube Neutrino Observatory in low-key, even humble, terms to a recent Madison meeting of the Wisconsin Innovation Network, Wiley jolted the crowd with a description that left no doubt about how he felt about the project.
Wiley called the decade-long effort to build a giant sub-ice telescope in the Antarctic “heroic,” given the unrelentingly harsh conditions at the bottom of the world, and compared IceCube to engineering feats as renowned as the Pyramids of Giza and the Panama Canal.
Perhaps there’s a bit of hyperbole in Wiley’s remarks, given his long association with the UW-Madison and his pride in a project that exemplifies the university’s expertise in exploratory science. But when people turn a billion tons of pristine ice into a telescope searching for one of the most elusive particles in the universe, a certain amount of bragging is OK.
Completed about two months ago after 10 years of research, planning and construction, IceCube is the world’s largest neutrino observatory. It was built at a cost of $271 million, mostly from the National Science Foundation, to find extremely high-energy neutrinos – tiny subatomic particles –originating from supernova explosions, gamma ray bursts and black holes. Scientists believe it will dramatically expand knowledge of astrophysics and “dark matter,” which makes up much of the universe.
Unlike other large-scale science projects, IceCube began collecting data while construction was underway and has been recording particle events since early 2005. Each year, as the detector grew, more and higher-quality data made its way from the South Pole to UW-Madison and around the world. IceCube is now recording about 100 neutrino passages daily, a startling number given scientists once believed they would never actually “see” a neutrino.
Neutrinos are excellent cosmic messengers. With no electrical charge and almost no mass, they pass unscathed through most matter, moving through the universe in a direct path from their cosmic origins. IceCube can detect neutrinos and other subatomic particles thanks to 86 optical sensor strings sunk deep in the South Pole ice. How deep? About two kilometers, which means the 5,160 individual sensors on those strings are using 10,000-year-old ice as a three-dimensional telescope to see what otherwise cannot be seen.
The process of drilling into the ice below the NSF’s Amundsen-Scott South Pole station was an engineering marvel, made only more difficult by perpetually frigid temperatures (the record high is 7 degrees and the winter average approaches -100 degrees). Much of the work was coordinated through the UW-Madison, one of about three-dozen partners from nearly a dozen nations.
If IceCube sounds like a giant science project to keep a bunch of astrophysicists happily occupied in a search for the unknown, that’s true. That’s how a lot of science works. In fact, most practical applications of science over time were the coincidental or even accidental results of research done for the sake of discovery.
“In the end,” Wiley said, “our goal is to provide insights into the nature of neutrinos and the universe that might someday be used to make the science fiction of today the reality of tomorrow.”
DuVernois said some reality may be emerging. Commercial opportunities surrounding IceCube already includes innovation in drilling technologies, electronics, software and field techniques. The future may also yield breakthroughs in radio detection, phototube replacement, scintillation crystals, forecasting disruptive solar storms and more. On the pure exploratory side, early mapping of particle paths shows “currently unexplained patterns” about cosmic ray arrival directions.
Exploratory science doesn’t always pay off in a commercial sense right away. In fact, it rarely does. The IceCube Neutrino Observatory is nonetheless an example of how “Big Science” can benefit everyone – and how researchers in Wisconsin have played a crucial role.
Still is president of the Wisconsin Technology Council. He is the former associate editor of the Wisconsin State Journal.
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