What is a micrometeorite?

A micrometeorite refers to extremely small particles, typically on the order of a few micrometers in size, that are composed of cosmic material. These tiny fragments originate from various sources in space, such as comets, asteroids, and even the solar wind. Due to their small size, micrometeorites can travel through the Earth's atmosphere and reach the surface, where they are often collected for scientific study. Understanding micrometeorites is crucial for studying the composition of celestial bodies and the processes that occur in our solar system. The other options fail to capture the essence of what a micrometeorite truly is, as they either refer to larger celestial objects or misinterpret the scale and impact of these tiny particles.