Astronomers in Antarctica are kicking off a new way of studying the cosmos. Rather than studying light, researchers now plan to study neutrinos from outside of our solar system. These hard-to-detect particles can carry new information on distant galaxies. Unlike light, neutrinos can pass through most all matter in their path, allowing researchers to see exactly where they came from and to learn more about black holes, supernovas, and other cosmic occurrences.
"The era of neutrino astronomy has begun."
Though neutrinos have been known about for some time, and were detected in one isolated experiment in 1987, researchers have since only able to detect ones from within our own solar system. In an article published today in Science, researchers from the IceCube Neutrino Observatory in the South Pole detail the detection of 28 of them, which they say must have originated farther out in the cosmos.
"We see neutrinos every six minutes, but they are of [little] interest … to us," says Francis Halzen, principal investigator at the observatory that detected the particles. "What we want to see are a handful of events sent to us by the [distant] universe. We have finally discovered those."
Because neutrinos pass through most matter, detecting them is a tricky task. To do so, researchers at IceCube burrowed through a mile of ice to place their detectors deep underground where neutrinos would be forced to interact with a large amount of matter in front of them. Though the detectors don’t spot the neutrino itself, they do see a very small amount of light that’s let off when one interacts with the ice. From there, the researchers determined how energetic each neutrino is — these 28 included some of the most energetic neutrinos ever seen, more energetic than what’s expected from inside our solar system.
Now that scientists have detected the neutrinos, the next step is to study where they came from. "The era of neutrino astronomy has begun," Gregory Sullivan, a University of Maryland researcher who contributes to IceCube, says in a statement. "The sources of neutrinos, and the question of what could accelerate these particles, has been a mystery for more than 100 years. Now we have an instrument that can detect astrophysical neutrinos. It's working beautifully, and we expect it to run for another 20 years."