How did Venus lose its water and become the “planet of hell?”

Why is Venus drier than Earth? A research team is trying to get to the bottom of this question and find an explanation for this phenomenon.

BOULDER – Venus is Earth's neighbor planet and is actually quite similar to it: the two planets are the same size and both are rocky planets. But there is a serious difference: “Venus has 100,000 times less water than Earth, even though it is essentially the same size and mass,” explains Michael Chaffin, a researcher at the University of Colorado in Boulder. His colleague Eren Kanji adds: “Since water is important for life, we need to understand the conditions that support liquid water in the universe and how Venus became so dry.”

Together with a team, the two investigated how Venus lost its water. The study was corresponding In the specialized magazine nature published. Compared to Earth, Venus is completely dry: if all of Earth's water were distributed over its surface, our planet would have a layer of liquid about three kilometers deep. On the other hand, on Venus, there would only be a layer three centimeters thick, the researcher explains.

The flower dried up and the ground remained wet

But how can this happen when the ground is wet? “We're trying to figure out what little changes happened on each planet to put them in these very different states,” Kanji explains in one article. notice Their university.

Research assumes that Venus received a similar amount of water as Earth when it formed. However, at some point in Venus's past, a catastrophe struck: clouds of carbon dioxide in the planet's atmosphere caused extreme global warming that increased temperatures on Venus' surface to around 500 degrees Celsius. Today, Venus is considered the “hell planet” due to its extreme temperature and enormous pressure. The heat caused most of the water on Venus to evaporate and disappear into space. However, this event alone cannot explain why Venus is dry today and how it continues to lose water

Venus has lost almost all of its water

Chaffin has an easy-to-understand analogy: “Suppose I pour water into my water bottle. There are still a few drops left,” the researcher explains. “However, on Venus, almost all of those remaining drops have also disappeared.”

Using computer models that depict Venus as a giant chemical laboratory, the research team discovered that a molecule called HCO+ in Venus' atmosphere appears to be responsible for the disappearance of water. HCO+ is an ion composed of one hydrogen atom, one carbon atom, and one oxygen atom. According to the research team, water and carbon dioxide form HCO+ in Venus' upper atmosphere, a molecule that the research also believes is responsible for Mars losing so much of its water.

A chemical process in the atmosphere of Venus causes some of the water to disappear

The process on Venus is supposed to work like this: HCO+ is constantly produced in the atmosphere, but individual ions do not survive for long. Electrons in the atmosphere find these ions and split them into two. Hydrogen atoms escape and can also escape into space, and Venus is missing one of the two components of water.

The study shows that the planet's dry state can only be explained if there are greater amounts of HCO+ in its atmosphere than previously expected. “One of the surprising conclusions of this work is that HCO+ should actually be one of the most abundant ions in the atmosphere of Venus,” says Chaffin. However, scientists have never observed this molecule in the atmosphere of Venus. The research team suspects that this is due to the lack of tools that can search for it properly. On the other hand, oxygen has already been discovered.

A future NASA mission will not be able to search for HCO+ on Venus

So far, only a few space missions have visited Venus, but there will be new missions in the future. NASA's next mission to Venus, called Da Vinci, will not be able to detect HCO+. But Kanji is already looking to the future: “The newly planned missions will leverage decades of collective experience and growing interest in Venus to explore the extremes of planetary atmosphere, evolution, and habitability.” (unpaid bill)