Interplanetary Dust Particles

Space is not empty. Certainly the smallest “bodies” in the solar system, interplanetary dust particles, or IDPs, are microscopic. This one (above left) is about a tenth the width of a human hair, and is composed of glass, carbon, and a conglomeration of silicate mineral grains (akin to beach sand). IDPs are bits of material from the early days of our solar system. They can be captured then later ejected by a passing comet. This IDP was collected by an aircraft flying high in Earth’s atmosphere. In 2004, NASA’s STARDUST mission passed through the tail of comet Wild 2, collecting cometary particles and returning them to Earth for study. Primitive material like this offers scientists a glimpse into the conditions of the early solar system.