"...For 19 days, ATIC circled the South Pole, studying cosmic rays coming from space. Then, nearly a year later, the ATIC team made a stunning announcement: they found that more high-energy electrons had left their mark on the experiment than expected. That might not sound like much, but the result is remarkable because it might be a telltale sign of dark matter, the invisible stuff thought to make up about 85 per cent of matter in the universe.

And it's not the only one. Just months before, an Italian-led collaboration reported that their satellite-based experiment, called PAMELA, had seen a similar excess of electrons, along with an excess of positrons. Add to this earlier results from gamma-ray satellites and experiments searching for dark matter here on Earth, and suddenly we have an abundance of new clues about dark matter. "It is a very exciting time to be doing dark-matter physics," says Dan Hooper, a physicist at the Fermi National Laboratory in Batavia, Illinois.

The bonanza of evidence suggests that dark matter might be far more complicated than we had ever imagined. For starters, the theoretician's favourite dark-matter candidate is falling out of favour, with the latest experiments making the case for new, exotic varieties of dark matter. If they are right, we could be living next to a "hidden sector", an unseen aspect of the cosmos that exists all around us and includes a new force of nature.

The bonanza of evidence suggests that dark matter might be more complicated than we ever imagined

Such hidden worlds might sound strange, but they emerge naturally from complex theories such as string theory, which attempts to mesh together the very small and the very large. Hidden worlds may, literally, be all around us. They could, in theory, be populated by a rich menagerie of particles and have their own forces. Yet we would be unaware of their existence because the particles interact extremely weakly with the familiar matter of our universe. Of late, physicists have been taking seriously the idea that particles from such hidden sectors could be dark matter.

We know precious little about dark matter, but we do know that its gravity is what keeps galaxies and clusters of galaxies from flying apart, despite the staggering speeds of the individual stars and galaxies within them. We also know that it must be made of particles that are massive and interact only very weakly with their surroundings. Anything that matches this description is known as a weakly interacting massive particle...." (New Scientist)

When I was in junior high the WIMPS were easy to find. They were the last ones out to recess and the first ones back in their seats...