Venus, often called Earth’s "evil twin," presents a stark contrast to our planet despite their similar sizes. With surface temperatures high enough to melt lead and clouds rich in sulfuric acid, Venus's harsh environment has long intrigued scientists.

Some hypothesized that Venus might have once been cooler, with oceans of liquid water. However, recent studies suggest the planet likely never possessed conditions necessary for sustaining life.

A new analysis of Venus's atmospheric composition indicates that its interior is extremely dry, a finding that challenges the idea that Venus once had liquid water oceans. Liquid water is considered a crucial element for the origin of life.

"This doesn't entirely rule out the possibility of life, but it does exclude Earth-like life," explained Tereza Constantinou, the study's lead author from the University of Cambridge.

The question of whether Venus was ever habitable—or whether its acidic clouds might still harbor life—has been a central topic in planetary science. Some scientists argue that Venus might have been Earth-like before succumbing to a runaway greenhouse effect, while others believe Venus was never suitable for life.

Constantinou noted that early in Venus's formation, its surface was likely covered by massive magma oceans. If these cooled rapidly, water vapor could have condensed to form liquid water oceans. This process would also have locked water within crystallizing magma, creating a water-rich interior that volcanic activity could later release.

“Look at Earth's volcanic eruptions; they release huge amounts of steam, most of which is water vapor,” Constantinou said.

However, if Venus’s magma cooled more slowly, water vapor might have remained in the atmosphere instead of being trapped inside the planet. In this scenario, volcanic eruptions would not have been a significant source of water.

In a study published in Nature Astronomy, Constantinou and her team analyzed Venus's atmospheric chemistry to determine its interior water content. They discovered that the rate at which substances escaped Venus’s atmosphere matched the rate of replenishment from volcanic activity. Crucially, the water content supplied by volcanic eruptions was minimal, suggesting that Venus’s interior is also extremely dry.

"The lack of water in volcanic emissions reflects the dryness of Venus’s interior," Constantinou explained.

The findings strongly suggest that Venus likely never had liquid water oceans, and therefore never experienced a climate suitable for life as traditionally defined.

This conclusion could soon be further tested. NASA’s upcoming DaVinci mission, planned for later this century, will fly by Venus and deploy a probe to its surface.

Constantinou emphasized that resolving this question will help astronomers refine the search for habitable exoplanets. “Earth and Venus provide an excellent laboratory for studying how habitability develops or disappears,” she said.