Underground Antarctic ‘telescope’ to trace cosmic rays

LONDON - A “telescope” buried deep under Antarctic ice has detected the first signals that scientists hope will allow them to identify the source of mysterious particles that bombard Earth from outer space.

For the past 10 years, scientists have been planning and building an ambitious experiment to explain the mystery of what produces the cosmic rays and elusive particles known as neutrinos, which constantly pepper our planet.

They have buried thousands of sensors more than a mile below the surface of Antarctica’s ice cap to record fleeting flashes of blue light that are given off when these high energy particles and rays collide with atoms in the ice.

By recording the pattern of light from the collisions, the sensors can plot the trajectory of the particles and rays, allowing scientists to pinpoint where in the galaxy they came from, reports the Telegraph.

Analysis has already begun of the results from the $271 million IceCube Neutrino Observatory - described by scientists as a “telescope” - although the last of its sensors is not due to be installed until December.

It has revealed a hot spot of galactic cosmic rays coming from an area close to the constellation of Vela, which appears in the shape of a ship’s sail in the skies of the southern hemisphere.

Recent research suggests that galactic cosmic rays may change the Earth’s climate, affecting weather and cloud cover.

Subir Sarkar, particle astrophysicist at Oxford University, Britain, who leads the British involvement in the IceCube experiment, said: “Cosmic rays were discovered 100 years ago, but we still have no idea where they come from.”

“At first glance, IceCube seems like a crazy experiment. How can you study the sky when you bury your detectors a mile beneath the ice? But it gives us a new way of tracing their paths back to their source,” said Sarkar.

When high energy particles in the cosmic rays smash into other matter, radiation and neutrinos are created.

After light, neutrinos are the most abundant particles in the universe. But it is extremely difficult for scientists to detect them because they have no charge and almost no mass, meaning they can pass through rock, metal and even human bodies without effect.

Very rarely a neutrino will strike an atom, producing another particle called a muon and a shock wave, which results in a burst of blue light - which the sensors will record.