Cosmic dust

Cosmic dust

. This interplanetary dust particle is probably of cometary origin. It is a mere one ten thousandth, or 0.0001, of a meter long. The particle was collected at 20 thousand meters altitude by a U-2 aircraft, and then photographed with a magnification of 16,000 using a scanning electron microscope. The embedded rod-shaped crystals were probably formed in the primeval solar nebula from which the planets formed, or perhaps in the pre-solar interstellar environment. (Courtesy of Donald E. Brownlee.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University