Find the 'oldest' space dust on earth

Japanese geological experts said they found pieces of meteorite, or dust, falling to Earth 240 million years ago.

Space dust found in Japan - Photo : Wired.

According to Physorg , the research team led by Dr. Tetsuji Onoue ( Kagoshima University ) is studying a form of microcrystalline quartz at Ajiro Island.

Each year there are about 30,000 tons of space dust, mostly from comets and small planets, falling to the earth. However, it is difficult to find because they are microscopic and due to the way they spread after falling to the earth. In order to survive intact for 240 million years, Mr. Onoue's prototype must first 'survive' after being burned in the atmosphere (90% of the dust of the earth falls to earth).

After that, they will fall into some kind of sediment, covered and kept safe for thousands of centuries. At an estimated age of 240 million years, extremely small iron-rich globules of 'old' Onoue are about 50 million years older than any space dust found previously on earth.

In the report published in the journal Geology published earlier this month, Onoue described how to search for meteorites hidden in horn stone. First they have to crush the stone, then use a sieve to sift the ice powder. Next, the ready-to-clean powder is washed and filtered again with a magnet. Later, the experts examined the results with an electron microscope and found globular masses that were only about 10 microns in diameter (1 micron = 1 millionth of a meter).