Definition of micrometeoroid in US English:



  • A microscopic particle in space or of extraterrestrial origin that is small enough so that if it enters the earth's atmosphere, it will not burn up but drift to the earth's surface instead.

    • ‘The moon lacks the shield provided by even a thin planetary atmosphere, such as Mars, so lunar explorers will have to withstand the relentless bombardment of harmful solar radiation and pelting rain of micrometeoroids.’
    • ‘He or she points out that the shuttle would be less exposed to micrometeoroids and orbital debris at the altitude of Hubble than at the lower altitude of the space station.’
    • ‘Other factors include charged particle radiation, neutral atomic particles, magnetic fields, micrometeoroids, and changes in gravity, not to mention environmental factors imposed by the spacecraft itself and the launch vehicle.’
    • ‘A chemical analysis of impact crater residue allowed him to distinguish between impacts due to naturally occurring micrometeoroids and those due to artificial space debris.’
    • ‘Hazardous micrometeoroids and radiation also threaten spacewalkers, and with no atmosphere and therefore no atmospheric pressure, fluids in the human body would boil.’
    • ‘If a micrometeoroid or piece of space debris penetrates the tank, the dregs can ignite, causing an explosion that shatters the rocket body and creates a cloud of debris.’