This planet has clouds but no rain, and humans are bent on exploring it, only to have 9 probes taken out

Last summer, China, Israel, and the United States all launched Mars probes, the first time in human history that three countries launched Mars probes in the same year, which set off a worldwide discussion about the exploration of Mars. When people are talking about the possibility of future human migration to Mars, how can we not think that another planet that has been more concerned than Mars a few decades ago, is Venus?

In the 1950s, Soviet scientists began to study Venus and came to the preliminary conclusion that Venus is the "sister planet" of Earth. This conclusion excited scientists from other countries, and if Venus was really like Earth, humans could migrate to Venus in the future. However, in the 1960s, the Soviet Union started to launch probes to explore Venus and made several attempts to land the probes on Venus, but it turned out that the real environment of Venus was more than expected, which gradually made scientists give up their illusions about it.

So what is the real environment of Venus that scientists are discouraged from exploring it?

What kind of attempts did the Soviet Union make in the early exploration of Venus?

According to historical records, the Soviet Union started to launch Venus probes in 1961, and the first one was Venus 1, which was the first probe to Venus in human history. Before the launch, the Soviets had many hopes for Venus 1, but in the end, Venus 1 failed the Soviets, it lost contact with Earth at a distance of about 96,000 kilometers from Venus, and Soviet scientists tried but could not contact Venus 1, the first Soviet exploration of Venus was declared a failure.

Six years later, the Soviet Union launched Venus 4. After several tests, the Soviet Union had accumulated some experience, so this time Venus 4 successfully entered the orbit of Venus and sent back data to Earth for the first time. It is understood that Venus 4 entered the atmosphere of Venus with significant resistance and its speed dropped to 300 meters per second. It traversed the atmosphere for roughly 1.5 hours before preparing for a hard landing. Just as Venus 4 was preparing to land, the accident happened again, and it lost communication with the ground.

Later, after analysis by Soviet experts, the antenna of Venus 4's landing module might have malfunctioned, causing the loss of communication, with the result that its landing could not be controlled by the ground crew and had a high probability of crashing on the surface of Venus. After several strikes, the Soviet Union still did not give up the exploration of Venus, some experts believe that this may be the result of the U.S.-Soviet space race at the time, the United States has achieved unsurpassed success on the moon landing, the Soviet Union can only achieve the same success on Venus, to match the United States.

So in 1970, the Soviet Union's Venus 7 was launched and made the first successful soft landing on the surface of Venus. Venus 7 also sent back to the ground the first data on the pressure and temperature of Venus, which showed that the atmospheric pressure on the surface of Venus is 90 times stronger than the atmospheric pressure of the Earth, and the temperature is more than 450 degrees Celsius. In such an environment, Venus 7 did not last long before breaking communication with the ground.

What did the first probe to land on Venus find?

The first successful soft landing on the surface of Venus gave the Soviet Union increased confidence, so the Soviet Union went on to develop Venus 9 and Venus 10, which were launched on June 8 and 14, 1975, and entered Venus orbit on October 22 and 25, becoming a pair of probes that simultaneously explored Venus Venus. The pair of man-made probes took a full range of pictures of the surface of Venus, but the pictures taken showed that there were thick clouds in the atmosphere of Venus, and the surface of Venus could not be seen at all.

To further explore the surface of Venus, Soviet scientists directed Venus 9 to implement a soft landing, and finally, Venus 9 successfully placed a 4.3-ton lander on the surface of Venus. According to the Soviet scientists, the lander had already started its exploration work during the landing process, and as a result, it detected that the thickness of Venus' clouds was more than 30 kilometers, a thickness that is equivalent to spreading to the suborbital region when placed on the Earth's atmosphere.

In addition, the specialized instruments carried by the lander detected that the main components of the clouds of Venus are greenhouse gases and various acidic gases, such as hydrochloric acid, hydrofluoric acid, sulfur dioxide, and so on. When the lander was about to touch the ground of Venus, its pressure detector showed a significant deflection, and the index showed that the atmospheric pressure of Venus is 92 times that of the Earth, which is equivalent to 76 times the pressure of the pressure cooker commonly used at home and 92 times the standard atmospheric pressure of the Earth.

Soviet scientists had already obtained these data from Venus 7, so they knew that if the Venus 9 lander was to be able to stay on the surface of Venus for a longer time, they would have to use special materials to build its shell. So the developers referred to the armor design of the Soviet Type 82 heavy cruiser at the time to create a shell for the lander that was also resistant to high pressure and impact. Some experts at the time believed that the Venus 9 lander used the world's most pressure-resistant technology, but it ultimately lasted only 53 minutes on Venus.

After the detection of Venus 9 lander, 96% of the composition of Venus' dense atmosphere is carbon dioxide, and 3.5% is nitrogen, the rest of the gases are some unfavorable gases for biological survival, such as sulfur dioxide, hydrofluoric acid, ammonia, etc. Because the clouds of Venus are very thick, so many scientists believe that there should be frequent rainfall on Venus, however, the lander found in less than an hour of exploration, that the surface of Venus is very dry, and the air humidity is also very low.

This means that Venus is a planet where it rarely rains, which is somewhat counterintuitive for a planet full of clouds, what is the reason behind this? Scientists later discovered the main reason when studying the temperature of Venus, it turns out that the temperature of the surface of Venus up to more than 460 degrees Celsius caused the rainfall to evaporate in the process of falling. This happens because, on the one hand, the clouds of Venus are very high and the rainfall has a rather long buffering process.

On the other hand, the greenhouse effect of Venus is very severe, causing the entire planet to be enveloped in a hot environment. So the question arises, how is the greenhouse effect of Venus formed?

How is the severe greenhouse effect of Venus formed?

For this question, there are different arguments in the scientific community. Some scientists believe that it is caused by the escape of the early Venusian atmosphere, ancient Venus may be the same as the Earth there is liquid water, oxygen, and other suitable environmental conditions, but later the Venusian atmosphere under the influence of solar activity escaped, resulting in a large number of atmospheric oxygen and water vapor escaped, most of the remaining gas is carbon dioxide.

Another important cause of the greenhouse effect on Venus is the presence of many active volcanoes on its surface. According to the Venus 9 orbiter data, the number of large volcanoes on the surface of Venus reached 167, their diameter is generally more than 100 km, the largest volcano in the solar system "Artemis" is located on Venus, according to its diameter of 2400 km, which is equivalent to the size of Australia.

In the 1990s, NASA's Magellan probe found thousands of volcanoes on the surface of Venus, as well as several erupting volcanoes. Volcanic eruptions further contribute to the greenhouse effect on Venus, as the ash that pours into the atmosphere further enhances the insulation of the surface, and the molten lava that gushes out from the volcanoes on a large scale directly raises the ambient temperature.

Why is Venus considered to be a "sister planet" of Earth?

Now, most people do not understand this statement, because the natural environment of Venus is very extreme, and it is not too much to describe it as a "hell planet". The claim that Venus is the 'sister planet' of the Earth has been around for a long time, and this claim also prompted the Soviet Union to carry out long-term Venus exploration activities. From some exploration data, Venus and Earth are indeed similar in many aspects. First, the size of Venus is similar to that of the Earth, and the radius of Venus is only about 300 km smaller than the radius of the Earth.

And the density of Venus is also slightly less than that of the Earth, which makes the mass of Venus not much different from the mass of the Earth. Second, both Venus and Earth have atmospheres. If you look at the entire solar system, there are very few planets that have an atmosphere, and the atmosphere is very important for the breeding of life and survival, so this is an important reason why Venus was considered similar to the Earth in the early days. Furthermore, both Venus and Earth have an equatorial inclination, which is not shared by other planets.

In addition, Venus and Earth are the closest planets in the solar system, a set of circumstances that led early scientists to speculate that Venus might be a "sister planet" to Earth.

Is phosphine a sign of life on Venus?

It is reasonable to assume that Venus' hellish natural environment would not be able to nurture life, much less the possibility of life, but a research paper in last September's Nature Astronomy has renewed interest in the topic of Venusian life. The paper noted that two telescopes located in Hawaii and Chile detected the presence of phosphine in the clouds of Venus. This gas also appears to occur on Earth but is generally associated only with life, i.e., microbes that produce phosphine through physiological reactions.

So after the news of "phosphine in the atmosphere of Venus", many scientists questioned whether there are microorganisms in the atmosphere of Venus. The authors of the paper and some scientists believe that the presence of phosphine does not fully explain the presence of microorganisms on Venus. Later a scientific team pointed out that the data in the research paper might be biased. In other words, the presence of phosphine in the Venusian atmosphere cannot be fully determined, and the heat of the topic of Venusian life has dropped again.