Chen Wen-ping explains that at present it is not possible to observe these small bodies directly. But when one of them happens to pass between a distant star and the earth, it will briefly "occult" (hide) the star by blocking its light.
陳文屏解釋，研究人員雖無法直接偵測這些小星體，但當它們恰巧遮掩到來自遙遠星星發出的光線，便可藉此估計出彗星數量。