On such worlds, “as far as we can tell, only life can make phosphine,” Dr. Sousa-Silva said. She has long studied the gas, on the theory that finding it being emitted from rocky planets that orbit distant stars could be proof that life exists elsewhere in the Milky Way.
Here on Earth, phosphine is found in our intestines, in the feces of badgers and penguins, and in some deep sea worms, as well as other biological environments associated with anaerobic organisms. It is also extremely poisonous. Militaries have employed it for chemical warfare, and it is used as a fumigant on farms. On the TV show “Breaking Bad,” the main character, Walter White, makes it to kill two rivals.
But scientists have yet to explain how Earth microbes make it.
“There’s not a lot of understanding of where it’s coming from, how it forms, things like that,” said Matthew Pasek, a geoscientist at the University of South Florida in Tampa. “We’ve seen it associated with where microbes are at, but we have not seen a microbe do it, which is a subtle difference, but an important one.”
Dr. Sousa-Silva was surprised when Dr. Greaves said that she had detected phosphine.
“That moment plays in my mind a lot, because I took a few minutes to consider what was happening,” she said.
If there really was phosphine on Venus, she believed there could be no other obvious explanation than anaerobic life.
“What we find circumstantially also makes complete sense with what we know thermodynamically,” she said.
The team needed a more powerful telescope, and the scientists next used the Atacama Large Millimeter Array, in Chile, in March 2019.
The startling carelessness about protecting Ms. Winner was particularly mystifying at an organization that had been founded on security. The Intercept had hired leaders in digital security, Ms. Clark and Micah Lee, for just such situations. Mr. Cole did not involve them at all.
Mr. Cole and Mr. Esposito said they’d been pushed to rush the story to publication, but Mr. Cole also acknowledged that failing to consult with the security team was a “face plant.”
The Intercept’s leaders argued in 2017, and still contend, that the narrative laid out by the Justice Department in its prosecution of Ms. Winner was shaped to make The Intercept — a thorn in the government’s side — look bad. And Ms. Winner’s own carelessness — she printed the document at work — could easily have gotten her caught even if The Intercept had been more cautious. But they also knew they had made real journalistic errors.
And so a key question was who to blame for this catastrophe and what consequences they should suffer. Ms. Dombek, who undertook the internal investigation, concluded that the editors — Ms. Reed and Mr. Hodge — needed to take responsibility. Others, including Mr. Greenwald, were demanding that Mr. Cole and Ms. Reed be fired, and The Intercept provide a public reckoning. (Mr. Greenwald later relented, and said he understood the desire not to “scapegoat” for an institutional failure.)
On July 11, 2017, Ms. Reed published a post on The Intercept announcing that First Look would pay for Ms. Winner’s legal defense. Ms. Reed also announced that an “internal review of the reporting of this story has now been completed.”
“We should have taken greater precautions to protect the identity of a source who was anonymous even to us,” she wrote. “As the editor in chief, I take responsibility for this failure, and for making sure that the internal newsroom issues that contributed to it are resolved.”
But the drama didn’t end there.
Mr. Greenwald and Jeremy Scahill, an investigative reporter who is the third founder of The Intercept, publicly demanded a more thorough investigation, and in response to their pressure, the company commissioned a second internal report, by a First Look lawyer, David Bralow. Mr. Bralow’s report, issued four months later, cited as central issues the decision to share the document with the N.S.A., Mr. Cole’s discussion of the postmark and the publication of the identifying markings.