Since the 1950s and the beginning of the “space race” scientists have wanted to practice astronomy and particle physics using high-energy neutrinos. So what’s stopping them? The challenge of building the kilometer-sized observatory they predict is needed to do the science. Enter IceCube, a revolutionary new design in neutrino detecting telescopes. Deep in the frozen wastelands at the South Pole, the world’s most extreme telescope will search for neutrinos from our Universe’s most violent astrophysical sources.
Those impossibly tiny particles known as neutrinos are produced by the decay of radioactive elements and elementary particles such as pions. Unlike photons or charged particles, neutrinos originate from deep within exploding stars, gamma ray bursts, and cataclysmic phenomena involving black holes and neutron stars and make their way throughout our Universe, eluding capture and study. Nothing stops a neutrino… Unless it crashes into an atom in ice.
When the rare neutrino collides with an atom in the ultra-transparent ice, it produces a muon that in turn radiates blue light. By observing this fluorescence, scientist can then detect the path of the muon and in turn the path of the neutrino. But, this kind of work really requires seeing in the dark – total dark. By using the Earth as a type of telescope optical tube assembly, neutrinos can enter into the North Pole just as photons enter into a primary objective lens. When they interact with the pure, uncontaminated ice at Earth’s South Pole it’s a whole lot like reaching a telescope’s secondary optic. The Earth itself, like an optical tube, keeps stray photons aways and the fluorescence produced with the muon can then be collected and studied.
So what’s all the fuss about neutrinos? Say Project IceCube: “The basic motivation is to understand our Universe, specifically what powers the most energetic engines in the cosmos and fuels the bombardment of cosmic rays to the Earth. We also want to understand the nature of Dark Matter. At the end, the stuff from which we are made is only 4% of the Universe’s inventory, whereas Dark Matter is 23%. These are motivations dominantly driven by curiosity, by the dream of mankind to understand our origins, our place in the cosmos, and a far future much beyond our human horizons.”
In short, IceCube is one cool telescope!
This material is based upon work supported by the National Science Foundation under Grant Nos. OPP-9980474 (AMANDA) and OPP-0236449 (IceCube), University of Wisconsin-Madison. Photo by Daan Hubert/NSF