Researchers at the University of Colorado Boulder have made a significant discovery about Venus, Earth’s neighboring planet known for its extreme conditions.
They’ve uncovered clues that may explain why Venus is so devoid of water, a vital ingredient for life as we know it.
Their findings, published in the journal Nature, delve into the intriguing processes happening in Venus’s atmosphere that lead to the loss of water.
Venus and Earth are similar in size and were once thought to have similar amounts of water. However, Venus is now almost completely dry compared to Earth.
If you imagine spreading all of Earth’s water evenly across its surface, it would form a layer about 3 kilometers (1.9 miles) deep. On Venus, this layer would be just 3 centimeters (about 1.2 inches) deep.
The team of planetary scientists used computer simulations to study the chemistry of Venus’s atmosphere, treating it like a giant laboratory.
They focused on a specific molecule, HCO+ (made up of hydrogen, carbon, and oxygen), which they suspect plays a crucial role in the disappearance of Venus’s water.
Eryn Cangi, a research scientist at the Laboratory for Atmospheric and Space Physics (LASP) and co-lead author of the study, explained that understanding how Venus lost its water could also help us learn about water retention on other planets across the galaxy.
The process that leads to water loss on Venus, known as “dissociative recombination,” involves HCO+ molecules getting broken down in the atmosphere.
This breakdown causes hydrogen atoms to be released and eventually escape into space. The new study suggests that Venus is losing about twice as much water every day as previously estimated due to this process.
Michael Chaffin, another co-lead author from LASP, likens Venus’s water loss to emptying a water bottle and watching even the last few drops evaporate. According to their research, this continuous loss of hydrogen atoms contributes significantly to the planet’s dryness.
Interestingly, despite the importance of HCO+ in this process, scientists have yet to directly observe it in Venus’s atmosphere. The researchers believe this is because past missions to Venus lacked the instruments needed to detect these molecules.
In contrast to Mars, which has seen numerous exploratory missions, Venus has been relatively neglected. However, interest in Venus is growing, and new missions are being planned. NASA’s upcoming DAVINCI mission, scheduled to launch by the end of this decade, will probe through Venus’s atmosphere down to the surface.
While DAVINCI won’t be equipped to detect HCO+, future missions might include the necessary tools to find this key molecule and further unravel the story of water on Venus.
As we continue to explore Venus, we gain valuable insights into the extremes of planetary atmospheres and their evolution, enriching our understanding of the conditions that support or hinder life.
This research not only sheds light on the past climate of Venus but also helps us consider the future of Earth and other planets in our galaxy.
