After nearly six months of mission, the Perseverance Mars rover finally held a groundbreaking ceremony. Early this morning, NASA’s newest Mars messenger drilled into a rock, and then extracted, sealed and stored a little finger-sized sample, and stored it in a tube in the protective compartment of his abdomen.
This seemingly minor geological theft marks the beginning of the return of Mars samples, a multi-agency, multi-mission effort aimed at bringing the tube-and more-back to Earth to provide scientists with They are the first original specimens from our neighboring world.For the entire Perseverance team and most planetary scientists, the significance of this sampling work Can not be exaggerated. Perseverance’s initial sought-after operation was the beginning of a more ambitious exploration that could completely change our view of Mars and life itself. Thanks to the sweat, blood and tears of generations of scientists and engineers, all this has been possible.
“There are hundreds of people, maybe even thousands of people who have contributed to the mission at one stage or another,” he said Sun Wei, The co-leader of the Perseverance Science Movement at NASA’s Jet Propulsion Laboratory. “You are standing on the shoulders of the task and the team in front of you.”
This sample is the first of as many as 43 samples that will return to Earth sometime in the 2030s. In a specially designed receiving laboratory, scientists will conduct forensic examinations of these precious materials in order to unlock the geological history of Jezero Crater, a basin interspersed with layered pie-like sediments and once home to short-lived lakes and river deltas ——And, maybe, Martian microbes. The first clear evidence of life beyond Earth may not come from anomalous flying objects, mysterious radio transmissions or space telescope snapshots of exoplanets, but from microfossils found in the humble rocks of the world next door.
This is how sampling happens—and what happens next.
So far, Perseverance, or “Percy” has been busy “settling” on Mars.When its robotic partner Ingenuity helicopter successfully flew around Jezero, Percy kept driving-sometimes Autonomously—Places to Visit, Shoot the stone with a laser, Capture More than 100,000 photos, Make a map Its surroundings and Modified oxygen From the atmosphere rich in carbon dioxide.
All of this is just the prelude to its main mission: to study rocks in search of ancient life. In theory, an epoch-making discovery may come from the on-board imager and chemical sensor of the rover, but before some of these rocks are brought back to Earth, any dunk discovery is unlikely to happen.of 43 samples Perseverance has the ability to collect, and its first came from an ancient geological unit called The pitted ground is broken and rough.
This is the rock type Perseverance that landed in February. It is worth noting that although Percy has been roaming on this rock since then, scientists still know very little about it. For example, they can’t say with certainty that it originated from volcanoes—and therefore may be one of the oldest rocks that the rover will encounter—or sediments, formed by covering older material with flowing water or wind. Solving this basic puzzle will help researchers accurately determine how and when Jezero modern geology was formed. “Whatever it is, it has incredible significance for the geological history of the entire basin,” said Justin Simon, NASA Johnson Space Center returned to the sample scientist with perseverance.
Earlier this summer, the Perseverance team selected a nearby dusty rock from the device that was ready to be drilled and used it for the long-awaited groundbreaking. After Percy wiped off the dust on a small surface, the rover brought two gadgets-X-ray Rock Chemical Planetary Instrument (PIXL) and Scanning Habitable Environment (SHERLOC) using Raman and organic matter and chemiluminescence The instrument—focus on the rock—learn more about its geochemical composition.
But only now has the “main incident” happened, explaining that Rick Welch, Perseverance project system engineer at NASA Jet Propulsion Laboratory. Thursday night, The ground controller sent a command to Perseverance to use its 2-meter-long robotic arm to approach and drill into the rock, and extract a cylindrical core sample similar in size to black chalk. The second, stronger robotic arm passes between the multiple chambers on the rover’s abdomen. The sample is magnified and photographed, and then finally sealed and buffered.
From the core to the cache, the entire process was completed in less than 8 hours-this is an impressive engineering feat. Scientists who are far-sighted have not forgotten this, especially those who are eager to see whether these priceless rocks are A scientist who contains evidence of life. “They are digging into the surface of Mars, for God’s sake,” said Jonathan Eisen, An evolutionary biologist at the University of California, Davis. “I mean, this is great!”
Looking for life
Current plans call for some samples of the rover to be left somewhere in Jezero, while others will be kept on Perseverance. Around 2028, the European Space Agency’s autonomous sample extraction rover should collect most or all of it and transport it to nearby NASA-sent Mars ascending vehicles, after which they will be launched into orbit. There, a European spacecraft will track and collect sample containers like a baseball glove catching a ball, and then return to Earth. These samples should land in the deserts of the western United States as early as 2031—most likely in Utah.
Sun said that this first sample from Cratered Floor Fractured Rough is unlikely to contain evidence of life, especially if the rock originated from a volcano—such as a lava flow. The most promising goal in astrobiology is the future of Perseverance: the part of the former lake bed where sediments once accumulated and the ancient river delta that transported this material from the surrounding area. However, due to the aridity, coldness, and irradiated surface conditions of Mars, these are also considered to provide slim opportunities for any living creatures.Any living microorganisms may be lurking in deep places that the earth cannot approach warm And possibly a more humid interior.That’s why, if there is life Yes Eisen and others say that what was found in Percy’s rock samples is almost certainly a biological contamination from the earth.
Of course, the chance of finding signs of ancient life is unknown. But Mars once had a planetary magnetic field that deflected radiation and more surface water. Whether life is transmitted to young Mars through meteorites from young Earth, or appears independently on this red planet, many experts suspect that it is likely to flourish in the early days of the world. “I don’t think we are actually likely to find evidence of the existence of a previous life,” Eisen said.
Simon said that searching for ancient creatures on Mars may actually be easier than searching for primitive life on land. The earth’s moving tectonic plates have destroyed most of the original crust, effectively erasing the existence of the earliest geological age of our planet. Mars never seemed to have plate tectonics, so ancient landscapes that may be home to life still exist today—assuming they were not covered by lava or destroyed by impacts.
Whether remotely on Mars or directly back to Earth, what exactly will astrophysical biologists look for when they study Perseverance’s rock transport?The mineral-rich structure produced by microorganisms is an obvious target, saying Maria-Pas Zorzano, A researcher at the Spanish Center for Astrobiology and a European return sample consultant for the Perseverance Team.
Optimistically, these structures will be similar to the earth’s stromatolites, layered microbiota. Although rare today, they are abundant fossils in some 3.5 billion-year-old rocks.But no one is betting on such a decisive discovery: most other Allegedly example The mineral structure created by very ancient creatures is theme of intense debateOn our own planet, structures believed to be the origin of organisms are often later proved to have non-biological origins.Extend this inference beyond the earth-as it is now infamous Putative microfossils in Martian meteorites——It is indeed an unstable prospect.
This is why any suspicious structure may need to be confirmed with biomarkers (molecules that somehow indicate the existence of life). Familiar biochemical pillars, such as DNA, RNA, and proteins, are not suitable for this type of search and are susceptible to degradation by radiation and geological activities. Zorzano said that lipids — fats used in cell membranes — can be stored for longer periods of time, so they can be used as markers of ancient life. The collection of other chemical substances related to life, including phosphorus, sulfur and various nitrogen-based compounds, may also last for several years. The same longevity can be applied to the changes in the elements that life likes as we know it-Lighter carbon, E.g.Chlorophyll and other biological pigments known to absorb specific wavelengths of light Keep some whole Spanning the geological age.
Zorzano said that if life on Mars is similar to life on Earth, such detective work would be easier. But the design of Martian microbes may be very different from that of terrestrial microbes, and more “unknowable” life recognition experiments are needed. These experiments are based on still vague assumptions, if any, physical rules apply to everything in the entire universe. Biological examples.
Even setting aside the ten-year timetable for sending samples back to Earth, the investigation of ancient life on them will be a long and long process: month by month, year after year, one by one, each of which may have to be eliminated. A non-biological explanation for any seemingly suspicious rock plaques. At the same time, any hypothetical biomarkers must still fit the broader context of the planet: if the “conclusive evidence” features of ancient biology only appear in rocks and record conditions that are known to be harmful to life, then researchers will only Can successfully find a deeper mystery. And learn for future generations.
Scientists may not be able to find signs of life on Mars. But, perhaps, they may succeed in doing this. If such a discovery proves to share a common evolutionary pedigree with life on Earth, it will be one thing: at least, we will know that we are not alone in the universe. But if we discover independent life on Mars, “from a scientific and philosophical point of view, its value will exceed the chart,” Eisen said. Such a discovery would strongly show that life can appear almost anywhere, just as flowers always seem to sprout from a long-forgotten brick wall. Life may be the rule of the entire universe, not the exception.
The return journey of the Mars sample has just begun. The end of this road is far beyond the horizon, and those who follow it cannot guarantee to reach the paradise of any celestial creatures. But dreaming that one day might find alien life hidden in Martian rocks is an undeniably fascinating idea. “Statistically speaking, there must be life in the universe. It is so big; it must be there,” Eisen said. “But until you actually find the evidence, it doesn’t mean much.”