There are 5200 tons of micrometeorites every year-Interplanetary dust from comets and asteroids Produce a meteor-reach the earth’s ground.
The calculation comes from an international project undertaken by scientists from CNRS (French Public Research Agency) and the University of Saclay in Paris for nearly 20 years, which has been published in the journal Earth and Planetary Science Letters.
Micrometeorites have been falling on our planet.These interplanetary dust particles from comets or asteroids Are a few tenths to one hundredth of a millimeter Through the atmosphere to reach the surface of the earth.
To collect and analyze these miniature meteorites, six expeditions led by CNRS researcher Jean Duprat Occurred near the Franco-Italian station in Concordia for the past two decades (Dome C), located 1,100 kilometers off the coast of Adelie Land in the center of Antarctica. Due to the low snow accumulation rate of the dome and almost no ground dust, the C-shaped dome is an ideal collection location.
These expeditions Collected enough extraterrestrial particles (Ranging from 30 to 200 microns in size) to measure their annual flow, which is equivalent to the mass accumulated on the earth per square meter per year.
If these results are applied to the entire planet, the total annual flux of micrometeorites Represents 5,200 tons per year. This is the main source of extraterrestrial material on Earth, far exceeding large objects such as meteorites, with a flux of less than ten tons per year.
Comparing the micrometeorite flux with the theoretically predicted value, it can be confirmed that most micrometeorites May come from a comet (80%) and the rest of the asteroids.
The study authors say this is valuable information that helps to better understand the role these interplanetary dust particles play in providing water and carbon molecules to the young Earth.