Has the James Webb Telescope found life at last? Solid, incontrovertible evidence of biosignatures on another planet? We write these words in the afterglow of a half-heard item on BBC News this morning, which so far (8.30 27 4 24 UK time) we can’t confirm anywhere on the web, including the BBC itself. The story is intriguing, not only because of the implications if it’s confirmed, but as as an example of how good science journalism should work. First, a little background.
Well-informed readers will the recall the media excitement last autumn, when provisional findings suggested that the James Webb Telescope had indeed detected the presence of methane (CH4), Carbon Dioxide (CO2) and Dimethyl sulphide (CH3)2S on the planet K2-18-b which lies about 120 light years from Earth in the constellation Leo.[1] That last molecule was particularly intriguing, because according to many, it can only be produced by living process. All the traditional media wrote it up. Certain news magazines, not always renowned for cool and reflective judgement, seemed to get more than a little carried away. Was this it? Was this, you know, them, ET and all that? At which point we turn to an excellent piece of journalism by Eric Berger of Ars Technica, a model of level-headed reasonableness which all of us would do well to imitate. In this racket, and many other walks of life. [2]
Instead of commenting on Press Releases and other journalists’ stories, Eric went back to NASA and got quotes. These it turned out, were much more subtle, nuanced and provisional. The signs of real knowledge in fact. The difference, in fact, between the provisional first interpretations of a crime scene examiner, and their write-up months later in a final statement, when all findings have been integrated with a much larger investigative process. And, above all, reflected upon.
Perhaps today, perhaps next week we’ll get more reports, both in the mainstreams and in the science journals which will help us confirm or deny this potentially exciting discovery. But when it comes we will still ask the following questions
1 Is there any possibility, however small, that DiMethyl Sulphide can be produced by non-biological processes?
2 How easy is it to distinguish the spectroscopic signature of DiMethyl Sulphide from other molecules?
3 Are there other molecules which indicate the presence of life, and if so, have they been detected on K2-18-b?
4 Are there other factors(the presence of noxious compounds, extremes of temperature or radiation, for example, which make life impossible, despite these hopeful findings.
We await today’s news with anticipation.
#dimethyl sulphide #ocean planet #james webb telescope #exobiology #alien #astronomy #spectroscopy
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