A new study may have solved the mystery of how water escaped from Venus


Today, however, Venus is a hellish world with intense heat and crushing pressure, and most of its water is gone.
We know that Earth is habitable, that Venus is too hot, and that Mars is too cold, but they both lost water.” Early on in Venus’ history, the planet may have lost a lot of its water through atmospheric escape.
As a result, scientists think that Venus lost part of its water due to solar wind hitting its upper atmosphere, causing the water molecules to escape over the 4,500 million years since the planet’s birth.
This process can remove a lot of the water, but it doesn’t account for how much water Venus has lost until today.
“We see such a low amount of water on Venus today, it doesn’t quite match.” The process through which Venus lost the rest of its water, and continues to lose its last remaining bits of the precious liquid until today, has puzzled scientists for years.
The new study suggests that Venus is losing water through a mechanism called dissociative recombination, whereby the positive ions of HCO+ are mixing with water and forming a positively charged molecule.
“That’s just a basic chemistry reaction, so that could have been going on in early Venus but continues through today, removing the last of that water,” Cangi said.
“But a mission like that would really complement the upcoming Venus mission suite to help us complete the picture of water escape from Venus.”


Venus and Earth were formed in the middle of a chaotic star system approximately 4^5 billion years ago. Given their similar sizes and structural similarities, the neighboring worlds are thought to have started off with comparable water volumes. All of Venus’s water has evaporated, and the planet is now a hellish place with extreme heat and pressure.

Though the exact cause of Venus’s transformation into a harsh desert planet is unknown, recent research points to a specific kind of molecule that may have escaped into space and drained the planet of its remaining water.

Using computer models, a team of planetary scientists from the University of Colorado Boulder investigated the chemical reactions occurring in Venus’ atmosphere and discovered that the arid conditions on the planet are probably caused by an ion known as HCO+, which is composed of one hydrogen atom, one carbon atom, and one oxygen atom. In the journal Nature this week, the results were published.

Co-lead author Eryn Cangi of the Laboratory for Atmospheric and Space Physics (LASP) and research scientist stated to Gizmodo that “the surface of Venus is about as hot as a pizza oven.”. On the spectrum of planetary habitability, Mars and Venus are two potential extremes. We know that Mars is too cold, Venus is too hot, and Earth is habitable—but they both lost water. “.

Venus may have lost a significant amount of water to atmospheric escape early in the planet’s existence. A stream of charged particles known as solar wind is continuously ejected by the Sun and can be seen beyond the planets and throughout the solar system. The solar wind strikes Venus, but fortunately, Earth has a magnetic field that protects it from it. As a result, scientists believe that during the 4,500 million years since the planet’s formation, some of the water on Venus was lost as a result of solar wind striking the planet’s upper atmosphere.

While much of the water can be removed by this process, the amount of water Venus has lost up to this point is not taken into consideration. Cangi stated, “I get rid of most of the water when I dump out my water bottle, but some drops remain in there.”. Venus’s water content is so low that it doesn’t quite match what we observe. “.

Scientists have been baffled for years by the mechanism by which Venus lost the remainder of its water and is still losing the last of the valuable liquid on the planet today. According to the latest research, Venus may be losing water due to a process known as dissociative recombination, in which water and the positive ions in HCO+ combine to form a positively charged molecule. A negatively charged electron will be drawn to the molecule because opposites attract, and they will combine.

But once they do, the resulting molecule has too much energy to remain intact, causing it to disintegrate. As a result of gaining too much energy during the joining and breaking-apart process, the hydrogen will eventually escape from the planet’s atmosphere. Cangi explained, “That’s just a basic chemistry reaction, so that could have been going on in early Venus but continues through today, removing that last bit of that water.”.

It is significant to note that the study did not directly detect HCO+ in Venus’ atmosphere because the instruments needed to look for the molecule in the atmosphere were not part of earlier missions to the nearby planet. However, information from earlier missions revealed evidence for some of the molecules involved in the reaction that forms HCO+.

The scientists behind the new study are proposing a new mission to Venus that will measure the molecules in its upper atmosphere because upcoming missions like VERITAS and DAVINCI won’t have the necessary instruments.

Cangi stated, “In science, we like to say that all models are wrong to some extent, but some are useful.”. However, a mission such as that would truly enhance the next suite of Venus missions to help us finish the picture of water escape from Venus. “.

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