In the outer solar system, phosphine is made deep in the interiors of Jupiter and Saturn. Near the giant planets’ cores, the temperatures and pressures are extreme enough to craft the molecule, which then rises through the atmosphere. But on rocky planets, where conditions are significantly less extreme, there’s no known way to make phosphine in the absence of life—it’s just too energetically demanding. In other words, if the observation of phosphine on Venus is right, something must be continually replenishing the molecule in the planet’s atmosphere.Nadia Drake, “Possible sign of life on Venus stirs up heated debate” at National Geographic
Still, ALMA observatory scientist John Carpenter is skeptical that the phosphine observations themselves are real. The signal is faint, and the team needed to perform an extensive amount of processing to pull it from the data returned by the telescopes. That processing, he says, may have returned an artificial signal at the same frequency as phosphine. He also notes that the standard for remote molecular identification involves detecting multiple fingerprints for the same molecule, which show up at different frequencies on the electromagnetic spectrum. That’s something that the team has not yet done with phosphine.Nadia Drake, “Possible sign of life on Venus stirs up heated debate” at National Geographic
The article offers lots of interesting stuff about how life forms could possibly survive in the clouds of Venus. There are several plans in the works for probes.
See also: Claim: Possible hints of life on Venus Based on discovering phosphine in the atmosphere.