Study Says Venus Held Oceans on 90% of Its Surface, Recasting 3 Feature Types as Marine
Updated
Updated · ScienceAlert · Aug 1
Study Says Venus Held Oceans on 90% of Its Surface, Recasting 3 Feature Types as Marine
3 articles · Updated · ScienceAlert · Aug 1
Summary
A new Earth & Planetary Science Letters study argues Venus still preserves signs of ancient seas, estimating water once covered about 90% of the planet with roughly 40% as much water as Earth’s oceans.
Richard Ghail’s team says three feature classes fit a marine origin better than a volcanic one: polygonal terrains like compacted seafloor mud, canali resembling submarine channels, and wrinkle ridges over evaporite salt deposits.
The reinterpretation challenges decades of readings based largely on NASA’s Magellan radar maps from the 1990s, which helped identify more than 85,000 volcanic features on Venus.
The case remains disputed because each clue could still be explained by volcanism or tectonics, but together the authors say they point to oceans lost in a runaway greenhouse less than 1 billion years ago.
ESA’s EnVision and NASA’s VERITAS missions are expected to map Venus in far greater detail, offering the next major test of whether those surface features truly record vanished oceans.