Giant Neutrino Telescope Planned for Mediterranean

An EU project will look for answers to the universe's mysteries by looking two miles underwater.

In an effort to unravel some of the universe's mysteries, the European Union has decided to fund a massive "telescope" that will sit at the bottom of the Mediterranean Sea to detect the presence of neutrinos passing through the Earth. (Because why not, right?) Construction on the $330-million project is set to begin within three years, although a scaled-down version of the Multi-Cubic Kilometre Neutrino Telescope, or KM3NeT, has already been installed off the coast of southern France. So, just what exactly is this thing, and how does it work? The whole point of the set-up will be to monitor and analyze neutrinos – sub-atomic particles released when stars go supernova, or when atoms collide – that pass through the universe. Understanding where they come from and how they work could lead to a greater understanding of the Big Bang and dark matter – the mysterious material that makes up about 80 per cent of the universe's mass, but has never been seen before.

KM3Net will be built on land, then lowered to the Mediterranean's sea floor, some two miles below the surface. The telescope will actually by a huge network of tethered, 12,000 spherical sensors floating in place throughout a cubic mile of water. Since neutrinos are so tiny, they regularly pass through matter without colliding. But seawater is dense – much denser than air – and the EU's astroparticle team thinks that seawater's physical properties will lead to more collisions with neutrinos, which produce a small flash of blue light. Those, in turn can be observed much better that far under water, where little to no light penetrates. The telescope will then determine the neutrino's path based on which direction the light flash was headed, which should help them find the source of the neutrinos. But, for cocktail party purposes, all you really need to know for now is that the EU is building a $330-million, cubic-mile, underwater telescope to figure out the universe 'n' stuff.