Does 'dark matter' matter?

Does 'dark matter' matter?

A rusty container, marked 'dark matter'

So far, the search for 'dark matter' has been unsuccessful

Researchers down a Yorkshire mine on their way to look for "dark matter"

But intrepid scientists continue to look in unusual places

You may have heard of the CERN experiment in Switzerland, which among other things, is trying to investigate "dark matter".

It cost around $7bn to set up, received an enormous amount of publicity, and has since broken down.

Well, there are other scientists around the world who are also trying to discover "dark matter" in different ways.

The BBC's "dark matter" reporter, David Whitty, has travelled a working potash mine in North Yorkshire, England, to visit one of the more unusual research experiments.

Listen Listen to his report (4 mins 54 secs)

First broadcast 7 January 2009

For more pictures of David Whitty's search for dark matter, click here.

For more from BBC World Service news programmes, click here.