UnprovenNot explained, but no evidence it is alien either. Usually too little data.
The claim
"A gas made by microbes on Earth was found in Venus's clouds."
Where the idea comes from
A team led by Jane Greaves reported phosphine in Nature Astronomy, using the JCMT and ALMA telescopes.
What the evidence shows
- On Earth phosphine is made mainly by microbes and industry, which is why the detection made headlines.
- Reanalyses found problems with the data processing; the ALMA signal shrank after a calibration error was fixed.
- Some argued the signal was sulphur dioxide; others suggested volcanic or unknown chemical sources.
- Follow-up observations have given mixed results.
What is still open
A Venus probe sampling the clouds directly (such as the planned DAVINCI mission) would settle it.
Our verdict
Unproven Disputed detection, with possible non-living sources.
Sources
Checked 31 October 2026. Spotted a newer source? Tell us.
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