According to a study published in the journal Nature Astronomy on September 14, two telescopes in Hawaii and Chile found possible signs of life in the thick clouds of Venus-the chemical characteristics of phosphine. Phosphine is a poisonous gas which is the only poisonous related to life on earth. New discoveries in the atmosphere of Venus indicate that microbes may be living in the sulfuric acid-laden clouds of this greenhouse planet.
The author of the study and some outside experts said that this is far from being the first hard evidence that life exists on other planets. In contrast, they called it “a suggestion to the possibility (the existence of life)”-although they all agree that this discovery does not satisfy the late Carl Sagan’s proposal, “special conclusions require significant evidence The strict requirements of “support”, but they cannot find a better explanation no matter in chemistry or geology.
“This is not a smoking gun or even the shooting residue on the hands of the main suspect, but there is a clear smell of gunpowder in the air (at the crime scene), which may suggest something.” One of the authors of the paper, London Empire David Clements of the Institute of Technology compares.
Astronomers plan to search for life on exoplanets in the future. One of the main methods is to look for biomarkers, that is, chemical features that can only be formed by biological processes. After meeting in a bar in Hawaii, the three astronomers decided to target the technology at the planet closest to Earth: Venus.
What they were looking for was an unknown substance: phosphine, which is composed of three hydrogen atoms and one phosphorus atom. Researchers say that there are only two ways to form phosphine on Earth. One is man-made production in industrial processes, including use as a chemical weapon in World War I. Another method arises from the functioning of animals and microorganisms that we have not yet the understood-this substance is also present in the bottom of the pond, in the guts of badgers and penguins.
Sara Siegel, a planetary scientist at the Massachusetts Institute of Technology and co-author of the study, said that the research team studied all the possibilities (of phosphine production): volcanoes, lightning strikes, meteorites falling into the atmosphere, and finally they Exclude one by one. They found that no activity on Venus could produce enough phosphine to explain the amount they detected.
“Therefore, we are left with only two weak possibilities. One is some unknown chemical reactions, and some chemical reactions we don’t know. The second, a more interesting possibility is that there may be some kind of life in the atmosphere of Venus. Form, produced the phosphine we detected.” Siegel added.
According to this study, phosphine may come from a certain microorganism, and most likely a single-celled organism. However, the surface temperature of Venus is about 800 degrees (425 degrees Celsius), which means that there is no water in any form on the surface. In order to explain how life survives on this uninhabitable planet, Siegel, Clements and his colleagues put forward a possible idea.
The research team believes that all life activities may occur 30 miles (50 kilometers) above the ground in a thick carbon dioxide cloud. The temperature there is about room temperature or slightly higher, and the atmospheric pressure is the same as the earth. These microorganisms may live in sulfuric acid droplets in the clouds. When the sulfuric acid droplets fall during Venus acid rain, these microorganisms may be dehydrated and then absorbed into another droplet in the clouds and resurrected.
Now, NASA has been studying two possible Venus missions, but has not yet made a final decision. One of the missions is called “Da Vinci+” and will enter the atmosphere of Venus as early as 2026.
Tianwen-1 completed the fourth midway correction of its orbit and returned the first image of Mars
At 20 o’clock on February 5, 2021, the engine of the first Mars exploration mission Tianwen-1 probe was ignited, and the fourth midway correction of the ground fire transfer section was successfully completed to ensure that Mars capture was carried out as planned.
Up to now, Tianwen-1 has been in orbit for about 197 days, about 184 million kilometers away from Earth, about 1.1 million kilometers away from Mars, and a flight mileage of about 465 million kilometers. The probe systems are in good condition.
Prior to this, Tianwen-1 acquired the first Martian image at a distance of about 2.2 million kilometers from Mars.
The hotel industry in Greece is experiencing a cold winter, and the total hotel business last year fell 78% year-on-year
Affected by the new crown pneumonia epidemic, the Greek hotel industry suffered heavy losses. The reporter recently visited several hotels randomly on the streets of Athens, most of which were closed. Some hotels that are still reluctantly operating are sluggish.
According to a recent report issued by the Greek Tourism Forecast and Research Institute, the total business volume of hotels in Greece in 2020 will be 1.831 billion euros, which is a 78% drop compared with 8.357 billion euros in 2019. Of the 3,965 hotels operating throughout the year, only 59% (2328) chose to reopen after Greece’s first total blockade in 2020, and 63% of the reopened hotels were forced to reopen before the end of 2020. As of the end of 2020, only 863 hotels in Greece remain in operation throughout the year, accounting for 22% of the total.
Although the Greek government has introduced financial incentives and subsidies to support the hotel industry, Alexandros Vasilikos, chairman of the Hellenic Hotel Association, pointed out that the Greek hotel industry will face many uncertainties and risks in 2021. He emphasized that continuing to strengthen liquidity is what the hotel industry urgently needs to do at present. This is not only related to the interests of the industry itself and employees, but also related to the interests of the Greek national economy and related supporting industries.
The potential mass range of dark matter is narrowed, helping to focus the search area
According to a report by the physicist organization network on the 27th, British scientists used the fact that gravity acts on dark matter to fundamentally calculate the mass range of dark matter for the first time. This range is much narrower than previously thought. The latest research has narrowed the range of potential masses of dark matter particles and also limited the search range for future dark matter “catchers”. It will also help scientists discover potential new forces in the future.
Dark matter does not emit light, emit electromagnetic waves, does not participate in electromagnetic interactions, and cannot be directly “seen” with any optical or electromagnetic wave observation equipment. Scientists have confirmed its existence through the effect of dark matter on galaxies. The result of the cosmic microwave background radiation observation experiment gives the proportion of dark matter in the total amount of cosmic matter. In the universe, ordinary matter accounts for only 4.9%, dark matter accounts for 26.8%, and dark energy accounts for 68.3%. Dark energy and dark matter are also considered to be two dark clouds in the physics sky at the beginning of the 21st century.
In the latest study, the research team led by Professor Xavier Kalmot of the School of Mathematics and Physical Sciences at the University of Sussex assumed that gravity is the only force acting on dark matter, and calculated that the mass of dark matter particles is between Between 10-3eV (electron volt) and 107eV, it is much narrower than the theoretically expected 10-24eV to 1028eV.
“This is the first time anyone has used quantum gravity to calculate the mass range of dark matter,” Carmott said. This study shows that unless there is a hitherto unknown force affecting it, dark matter cannot be like some theories. It is said to be “ultralight” or “overweight”.
The researchers believe that this research will benefit physicists in two ways: one is to focus on the search area of dark matter; the other is to help reveal whether there are mysterious unknown forces in the universe-if the mass of dark matter is found to exceed in the future The range predicted by the Sussex team indicates that dark matter is affected by other forces in addition to gravity.