Scientific debate over ancient Venusian oceans

Scientific research into the historical habitability of Venus has focused on the potential existence of ancient oceans. A study published in *Earth & Planetary Science Letters* suggests that Venus may have once possessed oceans covering approximately 90% of its surface. This hypothesis is based on a re-analysis of 1990s Magellan radar data, which identified features such as polygonal fault patterns and submarine-like channels that researchers interpret as marine sediments and salt layers.

Complementary NASA climate simulations using the ROCKE-3D model suggest that Venus could have maintained surface liquid water and moderate temperatures for nearly three billion years. These models indicate that if the planet’s primordial magma ocean cooled rapidly, steam could have condensed into rain and formed oceans, a state that may have persisted until volcanic outgassing approximately 700 million years ago.

Despite these findings, the presence of ancient oceans remains a subject of scientific debate. Some researchers argue that runaway greenhouse effects may have prevented water vapor from ever condensing, keeping water permanently in a gaseous state.