Scientists have found out how meteorites from Mars reach the Earth
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Of the thousands of meteorites on Earth, at least 188 are of Marisan origin. For example, the Northwest Africa (NWA) 7034 meteorite, nicknamed “Black Beauty”, hit our planet from an impact crater in the Terra Cimmeria – Sirenum region. Scientists have discovered that less pressure is needed for meteorites to break off and fall to Earth than previously thought. The corresponding study was published in the journal Science Advances, reports Science Alert. Read also: Why Venus and Mars are still unsuitable for human life. Where on Earth do meteorites from Mars come from? Meteorite Northwest Africa (NWA) 7034, nicknamed “Black Beauty”. Photo: NASA In the history of our solar system, there have been cases when asteroids hit Mars with such force that the debris flew into space. Then they drifted, entered the Earth’s atmosphere and landed. “Astronomers once thought that this was a complex process, and that only the most powerful collisions could hurl rocks from Mars into space. But new research shows that this requires much less pressure than previously thought, meaning that there could be more debris in space Mars, which float in the air and fly to Earth,” say scientists. A team of planetary scientists from the California Institute of Technology used a powerful new explosive cannon to simulate a collision with Mars. To avoid damaging the limited, precious supply of Martian meteorites, they used rocks from Earth containing plagioclase, which is a major component of Martian rocks. Under high pressure, such as when an asteroid collides, plagioclase transforms into a glassy material known as maskellinite. According to the researchers, the discovery of maskellinite in the rock indicates the type of pressure the sample was subjected to. “We’re not on Mars, so we can’t see a meteorite fall with our own eyes. But we can reproduce a similar impact in the laboratory. We found that a Martian meteorite launch requires much less pressure than we thought,” says Yang Liu, a planetary scientist. from JPL and co-author of the study. Experiments have shown that plagioclase transforms into maskellinite under a shock pressure of 30 gigapascals (GPa), which is 300,000 times the atmospheric pressure at sea level, or 1,000 times the pressure experienced by a submarine when submerged to a depth of 3 kilometers. Thanks to a new and improved blast gun, the study showed that the transition actually occurs at a pressure of about 20 GPa, which is different from previous experiments. Scientists recall: it was difficult to simulate an impact that could launch intact rocks from Mars. Elephant Moraine 79001 meteorite found in Antarctica. Photo: NASA “The more precisely we can characterize the impact pressure that the meteorite experienced, the more likely we will be able to identify the impact crater on Mars from which it was formed,” the article says. Last year, scientists were able to pinpoint that the Black Beauty Martian meteorite came from an impact crater in the Terra Cimmeria – Sirenum region of the Red Planet. “How do we know these meteorites are from Mars? Martian meteorites can be traced to the Red Planet because they contain clusters of trapped gas consistent with data from missions to Mars. Specifically, an experiment conducted by two NASA Viking spacecraft that landed on Mars in 1976, made it possible to measure the amount of various gases in the rarefied Martian atmosphere,” the scientists say. These same gases were found in 1983 in a meteorite called Elephant Moraine 79001 found in Antarctica. It will be recalled that NASA’s Curiosity Rover, while exploring the Gale Crater, found precious stones that could become a source of water on Mars. The scientists also said that there was probably no oxygen in the atmosphere of Mars at one time, but there could still be life forms on the planet. Read also: What would modern dinosaurs be like if they did not die out?
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