Rakesh Mogul, professor of chemistry and biochemistry, has revisited decades-old data from studies of Venus and uncovered evidence of previously overlooked water signals in the planet’s lower atmosphere. He explains how this “forgotten water” could reshape our understanding of Venus’s clouds and atmospheric chemistry. "The first thing we found was evidence of a phosphorus-based species in the clouds, where this thing, if it’s a phosphorus species, should be a gas,” he says. “The dominoes started to fall. What else is buried in this data? The big one was a water signal. There’s a lot of water, and especially in the deep lower atmosphere.”

This story was originally aired by NPR's "Looking Up Podcast" on November 21, 2025.