How did the water leave Venus? New research could solve the mystery

About 4.5 billion years ago, Earth and Venus were born in the middle of a chaotic star system. Neighboring worlds were the same size and similar structure. It is believed that both planets likely began with the same amount of water. Today, however, Venus is a hellish world of intense heat and crushing pressure, and much of its water has disappeared.

Scientists aren’t sure how it became a desert planet, but new research suggests the culprit may be a special type of molecule that escaped into space and drained Venus of its remaining water.

A team of planetary scientists at the University of Colorado Boulder studied the chemical reactions occurring in the atmosphere of Venus using computer models and found that a molecule called HCO+ (an ion made of hydrogen, carbon and oxygen atoms) is likely responsible. for the dry conditions of Venus. recommendations were published this week in the magazine Nature.

“The surface of Venus is as hot as a pizza oven,” Erin Kangi, a research scientist at the Laboratory for Atmospheric and Space Physics (LASP) and co-author of the new paper, told Gizmodo. “Venus and Mars are two possible ends of the planetary habitability spectrum. “We know that Earth is habitable, Venus is too hot and Mars is too cold, but they have both lost water.”

Early in Venus’ history, the planet may have lost most of its water due to atmospheric leakage. The sun constantly throws out water. Solar wind, a stream of charged particles that spreads throughout the solar system and beyond the planets. Earth is lucky to have a magnetic field that protects it from the solar wind, while Venus is exposed to it. As a result, scientists believe Venus lost some of its water due to the solar wind hitting its upper atmosphere, causing water molecules to abandon it within 4.5 billion years of the planet’s birth.

This process can remove most of the water, but it doesn’t take into account how much water Venus has lost to date. I throw out the water bottle, get rid of most of the water, but there are still a few drops in there,” Kangi said. . “We see so little water on Venus today that it doesn’t quite match.”

The process by which Venus lost the remainder of its water, and continues to lose the last of its precious fluid to this day, has puzzled scientists for years. The new study suggests that Venus loses water through a mechanism called dissociative recombination, in which HCO+ ions mix with water and form a positively charged molecule. Since opposites attract, the molecule will attract the negatively charged electron and they will combine.

However, once they do this, the resulting molecule has too much energy to stay together and therefore breaks apart. The hydrogen will go away. the planet’s atmosphere because it gained too much energy through the process of compounding and disintegrating. “It’s just a basic chemical reaction, so it could have happened on Venus before, but it’s still going on today, removing the remnants of that water,” Kangi said.

It’s important to note that the study did not directly detect HCO+ in Venus’ atmosphere; Previous missions to the neighboring planet lacked instruments designed to search for the molecule in the atmosphere. However, data from previous missions have shown that some molecules react to form HCO+.

Upcoming missions to Venus, such as VERITAS and DAVINCI, will also not be equipped with suitable instruments, so the scientists behind the new study are proposing a new mission to Venus that will measure molecules in its upper atmosphere.

“In science, we like to say that all models are wrong to some extent, but some are useful,” Kangi said. “A mission like this would really complement the next series of missions to Venus and help us complete the picture of water leakage from Venus.”

Further: 7 Weirdest Things About Venus, the Hell Planet