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NASA scientists continue to detect signs of life on Mars - the Red Planet. Will Mars become a 'second home' for humans in the future?
A mysterious crater on the side of an ancient volcano on Mars has recently been revealed beneath the surface of the Red Planet. The crater, just a few metres wide, was first photographed by NASAâs Mars Reconnaissance Orbiter, which was about 256 kilometres above the Martian surface at the time. It is one of several ridges seen on the flanks of a trio of large volcanoes in the Tharsis region of Mars. This particular crater was found on a lava flow above the extinct volcano Arsia Mons and appears to be a vertical shaft.
The mysterious lake on Mars was first discovered in 2021. NASA's InSight landed on Mars in November 2018 to observe the planet's interior, mapping soil layers and fault lines. On December 24, 2021, the lander made a major discovery when it picked up seismic waves from a large meteorite impact. The orbital images made the discovery even more remarkable because they revealed a huge new crater. "This is the largest crater we've ever seen," Ingrid Daubar, a planetary scientist at Brown University, said in a press release on October 27. "We think that craters of this size form on Mars every few decades. So it was really exciting to be able to witnes.s it, and fortunately it happened while InSight was recording seismic data."
In September, scientists on the InSight mission announced the discovery of four asteroid impacts, each creating a new crater, in 2020 and early 2021. But all were small impacts, none of which produced earthquakes larger than magnitude 2. The InSight team didnât expect to see signals from a larger impact, so the December 24 data from the InSight station came as a big surprise. The observations revealed a magnitude 4 impact that created a crater more than 430 feet (130 meters) wide.
While the InSight team was investigating the source of the impact, the Mars Reconnaissance Orbiter (MRO) also detected a large, fresh impact crater, said Liliya Posiolova, MRO mission science operations lead in California. Posiolova and her colleagues first saw the new crater in data collected by the MROâs Context camera.
According to Daubar, the crater is 150 meters wide, equivalent to two city blocks and 10 times the size of a typical crater on Mars. Based on the size of the crater, scientists estimate that the micrometeorite that hit the Red Planet was about 5 to 12 meters wide. The meteorite penetrated deep enough into the Martian surface to eject pebble-sized chunks of rock and water ice. Because the impact likely destroyed the meteorite completely, scientists believe the ice came from beneath the planet's surface. The crater created by the meteorite is located about 3,500 kilometers from InSight.
Scientists described the findings in two papers published on Aug. 27 in the journal Science. They may be the last published findings from InSight before the mission ends. The lander has very little remaining power due to dust accumulating on its solar panels. The stationâs seismometer currently observes only eight hours out of four Martian days. The InSight team expects the mission to end in the next few months.
Scientists have also discovered an ocean on Mars. Geophysicists have discovered a giant ocean hidden beneath the surface of Mars, and they think it could harbor life. The massive underground lake, discovered using seismic data collected by NASAâs InSight lander, contains enough liquid to cover the entire planet with a mile of water. However, it is too deep to be reached by any known means.
Trapped in a layer of fractured rock 11.5 to 20 kilometers below the Martian crust, reaching the water would require a drilling operation that is currently impossible on Earth. âWater is essential for life as we know it. I donât see why underground reservoirs wouldnât be habitable. Thatâs certainly true on Earthâdeep mines harbor life, the ocean floor harbors life,â said co-author Michael Manga, a professor of earth and planetary sciences at UC Berkeley. âWe havenât found evidence of life on Mars yet, but at least weâve identified a place that could, in principle, sustain life,â Manga added.
River channels, deltas and dried lake beds crisscross the surface of Mars, providing scientists with clear evidence that water once existed in abundance on the barren planet. However, about 3.5 billion years ago, a sudden change in Marsâ climate stripped the water from its surface. The cause of the rapid drying is still unclear, although scientists have hypothesized that it may have been caused by a sudden loss of the planetâs magnetic field, an asteroid impact or ancient microbial life disrupting the planet due to climate change. Coming up with a proper explanation and figuring out where the water went has become a crucial question.
By feeding this data into a mathematical model similar to those used to find underground water aquifers and oil deposits on Earth, scientists mapped the interior of Mars to figure out the thickness of the crust, the depth of the core, the composition of the core, and even a bit about the temperature inside the mantle, Manga said. Further investigation of the crust revealed that it most likely contains a fragment of broken-up igneous rock that contained enough liquid water to fill the Martian oceans, a sign that the water did not escape into space billions of years ago, but instead dripped down into the planet's crust.
While reaching the secret ocean is currently beyond human engineering capabilities (the deepest hole ever dug on Earth, the Kola Superdeep Borehole, only dug 7.6 miles into our planetâs surface), itâs not the only place scientists are looking for life on Mars. NASA originally planned a sample-return mission to launch around 2026, but that date has been pushed back to 2040 due to budget concerns. The agency is now soliciting proposals from private companies to speed up the mission.
Rộ tin nhân loại sắp bị diệt vong? 7 kịch bản tận thế khiến bạn mất ngủ! Khang Trần14:45:30 22/12/2024Nỗi sợ hãi về ngày tận thế luôn ám ảnh nhân loại. Từ tiên tri cổ xưa đến khoa học hiện đại, điều gì sẽ kết thúc thế giới? Thiên thạch, người ngoài hành tinh, hay chính con người? Khám phá những giả thuyết rùng rợn nhất về hồi kết của Trái Đất.
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