Scientists at Lund University in Sweden tracked meteorite impacts on earth that happened over the past 500 million years. To scientists' surprise, the influx of meteorites - space rocks - has been surprisingly stable despite major collisions happening in the asteroid belt of our solar system.
The asteroid belt is the area in our solar system covered by the orbits of millions of asteroids - frozen space rocks left over after the formation of planets. When a really small asteroid comes too close to earth so that it falls on earth crossing the planet’s atmosphere, it is called a meteorite These meteorites keep coming to the earth. However, back in the asteroid belt, when millions of rocks are circling around the sun together, collisions are inevitable. Scientists believed previously that these collisions might increase the influx of meteorites coming to earth.
“The new study, however, shows that the flux has instead been very stable", said Birger Schmitz, one of the astronomers who conducted the study, in a news release by Lund University.
Astronomers collected tonnes of sedimentary rocks from ancient seabeds. Scientists then dissolved the rocks into strong acids to sift out Chromium Oxide. The Chromium Oxide grains, which are very resistant to deterioration, work as a time capsule revealing information about the history of the rocks. Using the information from chromium oxide that came from almost 10,000 meteorites, the astronomers reconstructed 500 million years of past impacts.
Scientists were surprised by the result that “only one of the 70 largest asteroid collisions that took place over the past 500 million years resulted in an increased flux of meteorites to Earth," says Schmitz.
According to the scientists, for some unknown reason, the asteroids choose to remain in the asteroid belt rather than falling on the earth. The study was published in the June issue of Proceedings of the National Academy of Sciences journal.
The findings ease-out scientists from the long-coming worries of asteroids colliding with the earth. One such collision that happened 66 million years ago, wiped three-fourths of the plant and animal life on the planet.