The hidden giants
http://news.independent.co.uk/world/science_technology/story.jsp?story=564268

Under land and sea, in vast subterranean laboratories, scientists are
working to uncover the secrets of the universe, from 'dark matter' to
global warming

By Steve Connor
22 September 2004


The Kamioka Underground Observatory in Japan

A paradox in science is that the smallest and most ubiquitous things
imaginable can often only be detected by some of the biggest and most
expensive scientific instruments ever built. And most of them are so
sensitive they need to be shielded in deep subterranean caverns. The
Kamioka Underground Observatory in Japan is housed in an old mine
located 1,000 metres below ground. At its core is a giant tank of
ultra-pure water weighing some 3,000 tons and surrounded by 1,000
highly sensitive light detectors.

The water tank is 16m high and 15.6m in diameter. The 1,000
photomultiplier tubes fitted around the inside of the tank are there
to detect the tiny flashes of pale blue light that may be emitted as a
certain subatomic particle travelling at the speed of light collides
with the nucleus of a water molecule. This particle - called a
neutrino - has achieved almost mythical status in physics.

Sci/Technology
http://news.independent.co.uk/world/science_technology/