"micrometeoroid." YourDictionary, n.d. Web. 09 November 2018. <https://www.yourdictionary.com/micrometeoroid>.
micrometeoroid. (n.d.). Retrieved November 09th, 2018, from https://www.yourdictionary.com/micrometeoroid
An extremely small meteoroid, typically the size of a grain of dust. Particles measuring less than 0.05 mm (0.002 inch) in diameter are classed as micrometeoroids. Despite their small size, their high velocities mean that micrometeoroids pose a significant threat to spacecraft and artificial satellites.