At a recent scientific gathering in Vienna, researchers presented findings that scramble our assumptions about what kinds of planets the galaxy tends to make. Venus-like worlds—hellish, carbon dioxide-choked spheres with thick, crushing atmospheres—may be roughly twice as common as habitable ocean worlds like Earth, according to preliminary results shared at the European Geosciences Union General Assembly.
The discovery matters because it reframes how we think about planetary evolution and what we should expect to find as our technology for detecting distant worlds improves. "There are loads of rocky exoplanets since the galaxy is great at making rocks," Sean Jordan, a postdoctoral fellow in exoplanet studies at ETH Zurich, explained at the EGU26 conference. The real question isn't whether rocky planets form—it's what kind of atmosphere they end up with.
Jordan's research suggests it's quite plausible that Venus-type atmospheres form naturally during a planet's early magma ocean phase, making thick carbon dioxide atmospheres far more common outcomes than scientists previously thought. "Our preliminary results demonstrate that it's quite easy to construct a model scenario where a Venus-like atmosphere forms, straight from their magma ocean phase of planetary evolution," Jordan noted. At least a few dozen rocky exoplanets are currently considered potential Venus-like candidates, though none have been confirmed as such.
The work hinges on a profound realization about Venus itself. Rather than assuming Venus somehow "went wrong"—that it once had oceans and underwent a runaway greenhouse effect—Jordan argues it may simply have been born that way. "It's much easier for us to build a model where we end up with Venus as it is straight out of a magma ocean phase of its early evolution and formation," he says, "but it's quite difficult to construct a model where it can form and condense oceans, and then go through the runaway greenhouse boundary."
This insight carries implications for exoplanet detection. Most distant rocky planets discovered so far orbit red M-dwarf stars in close orbits, yet researchers remain uncertain whether these worlds retain atmospheres at all. Stellar radiation and particle fluxes from their host stars may continually strip away any atmosphere they possess, making atmospheric retention a major unknown. "Perhaps in a few years' time we'll find out that none of these rocky exoplanets around M stars have atmospheres," Jordan cautioned.
Understanding whether exoplanets harbor Venus-like or habitable atmospheres will require both better data about Venus itself and more sophisticated space telescopes. Notably, Venus remains criminally underexplored despite our ability to study its atmospheric composition down to trace abundance gases. "There's a real synergy between a more comprehensive understanding of our own Venus and a comprehensive understanding of the plethora of extrasolar Venuses that have yet to be confirmed orbiting other sunlike stars," Jordan explained. Each discovery about distant worlds informs our understanding of our own solar system, and vice versa.
The timeline for answering these questions definitively is measured in decades. Assuming proposed Venus missions proceed and future space telescopes launch successfully, researchers expect a clearer picture of how common exo-Venuses truly are within roughly twenty years. Until then, the preliminary evidence suggests the galaxy may favor crafting inhospitable rocky planets far more readily than Earth-like worlds—a reminder that habitability, it seems, is rarer than we thought.