The cosmos is much closer to us than it seems.The air on our planet is literally saturated with cosmic dust, which is formed during the destruction of comets, asteroids and other similar objects. And from time to time we breathe in tiny particles that were far away in space some time ago. Finding out exactly how much cosmic dust is on Earth is very difficult. The fact is that it is mixed with earthly dust particles, which are microscopic particles of everything that surrounds us. But recently, scientists have found a way to find out how many particles of cosmic dust fall on our planet. To do this, they had to go to distant Antarctica, collect materials and do some calculations. It turned out that about 5,200 tons of cosmic dust fall to Earth annually, which is a lot. Let's see why exactly the researchers had to fly to the icy continent and how did they come to the above conclusion?
How much space dust is on Earth?
The study and its results weretold in the scientific journal ScienceAlert. The atmosphere of our planet is saturated with dust of all kinds. According to the results of scientific work, at any given time, 17 million tons of coarse dust soars in the air. These are microscopic particles of our skin, rocks and all objects around us. It is impossible to separate dust of terrestrial origin from cosmic dust, and that is why scientists for a long time could not figure out exactly how much cosmic dust falls on our planet. But recently they found a trick that helped answer that question.
To "weigh" the amount of cosmic dust notConsidering the particles of terrestrial origin, the scientists went to the Antarctic Concordia station. It is located on the territory of the so-called "dome C", where there is practically no earth dust. By melting clean snow, scientists have been collecting clean cosmic dust for two years. In the investigated area, the authors of the scientific work managed to find particles with a diameter of 30 to 350 micrometers. Having determined their mass and recalculating the resulting figure, taking into account the entire surface of the Earth, scientists have come to the conclusion that about 5,200 tons of cosmic dust falls on our planet every year.
This is a huge number.According to the researchers, more cosmic dust particles fall into our atmosphere than meteorites. For comparison, the total mass of meteorites entering our atmosphere annually is less than 10 tons per year. This is no match for the 5,200 tons of cosmic dust. However, some sources say that up to 40,000 tons of dust particles enter the atmosphere every year, but I could not find a reliable source. So the results of this study are the most credible.
At the second stage of scientific work, scientists took updetermination of the origin of dust particles. To do this, they studied their density. If it is small and there are pores in the dust particles, then they are of cometary origin. And if the dust grains are dense and with little porosity, then they are of meteoric origin. In the course of studying the structure of particles, scientists have come to the conclusion that 80% of dust particles that fall on Earth are ejected by comets. This is the name of the small celestial bodies that move around the Sun and sometimes have a tail of gas and dust.
See also: Moon dust can be dangerous to humans
The emergence of life on Earth
According to researchers, the discovery madecan help in elucidating the causes of life on Earth. It is believed that water on our planet appeared after the fall of asteroids and other space objects. As part of scientific work, scientists have found that most of all cometary particles with a large number of pores get into our atmosphere. It can be assumed that it was thanks to cosmic dust that life arose on Earth. Or these tiny particles just contributed a little to it. For now, this is just a guess, so we need to wait for the results of the next studies.
If you are interested in science and technology news, subscribe to our channel in Yandex.Zen. There you will find articles that have not been published on the site!
There is a myth that dust is microscopicparticles of dead human skin. In fact, everything is not so simple and you can call anything dust. According to the International Organization for Standardization (ISO), dust is defined as particles with a diameter of less than 75 micrometers. If you want to know even more interesting facts about dust, read this article.