particle

The Northern Lights are caused by solar winds carrying charged particles interacting with the earth's magnetic field.

Rico said it’s a hot spot where the falling water forms bubbles that burst and send fine particles of pollutants into the air.

When averaged over the year, Imperial Valley and Salton Sea Basin have twice the state limit for larger particles.

“The concern was that in large concentrates the particles would be hazardous. But the cloud has since dissipated.”

Brake dust contains tiny bits of metal, black carbon and other particles that enter the air due to friction and the wearing away of braking materials.