‘How cosmic dust aggregates to form planets decoded’

NEW YORK :

RESEARCHERS have found how cosmic dust particles stick together and aggregate, leading to the formation of planets, an advance that may also improve dust handling in industrial processes. The researchers, including those from Rutgers University in the US, found that particles under microgravity -- similar to the conditions seen in interplanetary space -- develop strong electrical charges spontaneously, and stick together to form large aggregates.

Although like-charges repel, aggregates from similarly charged dust particles form since they are strong enough to polarise each other, making them behave like tiny magnets, the study, published in the journal Nature Physics, noted. “Once those aggregates have diameters exceeding a few centimetres, they become subject to concentration mechanisms such as the streaming instability, permitting the formation of self-gravitating clusters, which might eventually collapse into kilometre-sized planetesimals,” the researchers wrote in the study.

According to the researchers, similar dust aggregation processes exist on the Earth in chemical reactors used to produce everything from plastics to pharmaceutical drugs. In these manufacturing units -- called fluidised bed reactors -- they said, blowing gas pushes fine particles upwards, and when they aggregate due to static electricity, these particles stick to reactor vessel walls, leading to shutdowns and poor product quality.