Every time it rains.
Micro meteroites are inside most rain drops.
Approximately 5000 meteroids burn up in our atmosphere every day, high up in the air. 90 to 95% of them burn up completely. Some of them fall to the ground.
The ones that burn up don’t disappear. They become extraterrestrial dust. Eventually rain drops form around them and they fall from the sky.
Anywere from 3 to 500 metric tons of extraterrestrial matter falls to the earth every day. Earth is getting heavier.