An astronomical survey searching for small, icy bodies circling in the far reaches of the solar system has come up empty-handed.

After a two year serach, the Taiwanese-American Occultation Survey (TAOS), has concluded that there are no miniature sized plutoids - between three and 27 kilometres in diameter - in the Kuiper Belt objects.

TAOS has been watching for tiny flickers of light as small KBOs eclipsed background stars, a technique scientists thought would reveal objects too tiny to be spotted directly.

The survey accumulated more than 200 hours of data studying light from between 200 and 2000 stars simultaneously, but failed to detect any flickers.

Scientists suspect the dearth of small objects may be because bodies of that size have already clumped together to form larger bodies, or because frequent collisions have broken down the objects into even smaller bodies that fall below the survey's detection level.