Scientists have developed a working theory for how small clumps of dust become big balls of debris and begin to form young planets.
In protoplanetary disks, adhesion causes small particles of dust to stick together, just as it causes dust bunnies to form underneath furniture at home. Gravity causes larger objects to coalesce. But until now, scientists weren't exactly sure how small clumps of dust become large orbs of debris.
In protoplanetary disks, adhesion causes small particles of dust to stick together, just as it causes dust bunnies to form underneath furniture at home. Gravity causes larger objects to coalesce. But until now, scientists weren't exactly sure how small clumps of dust become large orbs of debris.
New research, published this week in the journal Nature Physics, suggests particles under microgravity conditions develop strong electrical changes causing them to spontaneously stick together.
Models developed by the study's authors showed even particles with like charges congregate because their charges are strong enough to polarize one another, causing the particles to rotate and join together like a magnet.
Models developed by the study's authors showed even particles with like charges congregate because their charges are strong enough to polarize one another, causing the particles to rotate and join together like a magnet.
"We may have overcome a fundamental obstacle in understanding how planets form," study co-author Troy Shinbrot, a professor of biomedical engineering in at Rutgers University-New Brunswick, said in a news release.
Researchers realized the electrical mechanisms dictating aggregate formation also show up in a chemical manufacturing setup called fluidized bed reactors, which is used to make everything from plastics to pharmaceuticals. When gas is blown through the reactors, fine particles are pushed upward. Static electricity causes them to accumulate and stick to reactor vessel walls, which can cause the manufacturing process to fail.
"Mechanisms for generating aggregates in industrial processes have also been identified and that -- we hope -- may be controlled in future work," Shinbrot said. "Both outcomes hinge on a new understanding that electrical polarization is central to aggregation."
Researchers realized the electrical mechanisms dictating aggregate formation also show up in a chemical manufacturing setup called fluidized bed reactors, which is used to make everything from plastics to pharmaceuticals. When gas is blown through the reactors, fine particles are pushed upward. Static electricity causes them to accumulate and stick to reactor vessel walls, which can cause the manufacturing process to fail.
"Mechanisms for generating aggregates in industrial processes have also been identified and that -- we hope -- may be controlled in future work," Shinbrot said. "Both outcomes hinge on a new understanding that electrical polarization is central to aggregation."
Additives that conduct electricity in a more productive way could be used to eliminate the problems caused by the use of static electricity.
In follow up studies, scientists hope to test how electrical-induced particle aggregation varies among different types of material.
In follow up studies, scientists hope to test how electrical-induced particle aggregation varies among different types of material.
