No small matter

DOES our universe have antimatter (theoppositely charged counterpart of ordinary matter) in substantial quantities?Do we have whole galaxies made up ofantimatter, much like our own galaxywhich is made up of matter? These aresome of the brainteasers which could becloser to a solution if MassachusettsInstitute of Technology physicistSamuel C Ting's efforts to finance anddevelop the Alpha Magnetic Spectro-Meter (AMS) bear fruit (Science, Vol 269,August 18,1995).

Antimatter is routinely createdand studied in the laboratory, but ithas rarely been observed in nature,Cosmic sources of antimatter are hardto detect because optical telescopescannot distinguish them from ordinarymatter sources.

However, scientists have demined that there are no antinusources within 30 million light yewour solar system. Nevertheless, aantiprotons have been observed iniloon experiments which have recolcosmic rays at heights of 40 km.reason for the paucity of data ismagnetic field of the earth which mit harder to spot these charged particles.

Now Ting plans to conduct anexperiment on a space shuttle. Orbitingat 300 km, it will be beyond the earth'smagnetic field and hence eminentlysuited for observing these particles. If the shuttle experiment is successhd.AMS will be put on a space station b)year 2001.

The strategy to observe these particles simple: using a huge I meterve mmpet@ the charges of antiparticles passing through the core of thepo am be measured. The hitch isdw rn-gnet will be made of rareh aL@ents which are available inmL 1U makes the project some-whati sommin. The political implicationsPefthe Chinese connection make ith* that the project will be fundedsoon, given the current state of relationsbetween the China and the us.

But Ting's tenacity is legendary. ANobel laureate in 1976 for his discoveryof the Jlpsi particle, Chinese-born Tingis reported to be already talking to theRussians and considering placing the 6-tonne AMS on Mir, the Russian spacestation. If the project succeeds, it winopen up a completely new window ontothe cosmos.