Illustration: This will never happen: Mars will prove its resistance to the earth's transformation.

Colonists hope to transform Mars into the earth for human beings to settle on Mars, but this may face obstacles. Scientists say that there is not enough carbon dioxide to significantly warm the earth.

Because of the role of carbon dioxide content in global warming, it is an environmental focus topic on the earth. But on Mars, global warming will make the production conditions of frozen wasteland on this red planet more livable.

Theoretically, solar mirrors or other heat sources can be used to release carbon dioxide from Martian rocks and polar regions, making its atmosphere thicker, which can keep its heat and make the planet more like the Earth.

Unfortunately, northern arizona university and Christopher Edwards, a planetary scientist in Staffordshire, Flug, said in a paper to be published in Nature-Astronomy that the answer is "No".

Once upon a time, Mars was rich in carbon dioxide-enough to warm the earth and produce oceans, rivers and temperate zones where we could feel the appropriate temperature.

Most of them have disappeared now, leaving an atmosphere with a surface pressure of only 6 mbar, or 0.6 times that of the earth's atmosphere, mainly including carbon dioxide.

According to MAVEN's measurement of the escape rate of Martian gas, it is likely that at least half a bar (500 mbar) of carbon dioxide will escape into space. "This figure may be closer to 1 bar," Jakovski said.

Many remaining carbon dioxide is frozen into ice in the polar regions of Mars, or reacts with rocks to form carbonate. But it is mostly adsorbed on the surface of the floating ice on Mars, or it may be isolated in a strange ice layer called Crarat. The frozen water will form a crystal cage to capture other gas molecules.

"What we do is simple math," Edwards said. "We calculated how much carbon dioxide escaped. Compared with the carbon dioxide that you need to transform Mars into a colony without a dome and spacesuit, this is what happened."

At best, it is. He and Jakovski found that the available carbon dioxide can only make the planet's atmosphere three times as large as it is now, and its pressure will reach about 20 millibars.

Doubling the density sounds like a lot, but 20 millibar can only increase the surface temperature by about 65,438+00 degrees Celsius-far below the temperature needed by the earth.

Having said that, there is still a lot of carbon dioxide that has not been taken into account in the study, including carbon dioxide in rocks deep underground on Mars.

How much will this exist? Jakovski said, "This is a big question. All we know is that there will be some here. It was exposed to some impact craters. But we can't quantify how many. More importantly, if buried too deep, they are actually inaccessible. "

However, supporters of globalization are not necessarily afraid. Chris McKay, an astrobiologist at the National Aeronautics and Space Administration's Ace Institute in Murphy, California, USA, said that MAVEN's results on atmospheric loss rate are actually conducive to the formation of globalization, because "almost all climate models show that there must be several bars of carbon dioxide in early Mars in history.

If so, only a small part will disappear into space, and the rest must still be somewhere.

MacKay also believes that it is only a simple guess to estimate how much may still lurk under the surface. "We don't have good data, and we need to dig deeper to get these data," he said.

Tracing back to 199 1, he added that he and his colleagues pointed out that whether Mars can be formed depends on the initial supply of key gases and how much they are lost into space. "It still is," he said.

In fact, he said, the real problem may not be greenhouse gases such as carbon dioxide, but nitrogen, which is an essential nutrient for life. "If nitrogen is not enough, all the earth will be impossible before the distant future.

Robert Sawyer, a Canadian science fiction writer, added that Mars also stores other potential greenhouse gases in liquid form, which may be largely locked in the ground. In addition, he also said that the planet can be directly heated by a large orbiting mirror, which focuses sunlight on the surface-an idea that has long been mentioned in scientific literature and science fiction.

"I have no doubt that in the next 50 years-from the first time we separated people from the lunar orbit to the present-we can have the technology to shape the terrain of Mars." He said.

Jakovski and Edwards did not object. In fact, when it comes to foreign suggestions, they even go further and think that there may be a theoretical opportunity to cover the earth's atmosphere with artificial gases, such as chlorofluorocarbon (CFS), which warms the earth more effectively than carbon dioxide. But they think that making these chemicals on the surface of Mars is beyond the coverage of the existing technology.

Jakovski said that everything we say is based on today's technical level, and you can't change the global environment. "I don't know where we will be in the next 20, 50, 100, or 200 years."

1.WJ encyclopedia

2. Astronomical terminology

3. Richard Loo Witt-Lyotireg

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