SoylentNews is people
SoylentNews
A new study suggests a biosignature that the James Webb Space Telescope could search for:
The new study looks at the history of life on Earth, the one inhabited planet we know, to find times where the planet's atmosphere contained a mixture of gases that are out of equilibrium and could exist only in the presence of living organisms — anything from pond scum to giant redwoods. In fact, life's ability to make large amounts of oxygen has only occurred in the past one-eighth of Earth's history.
By taking a longer view, the researchers identified a new combination of gases that would provide evidence of life: methane plus carbon dioxide, minus carbon monoxide.
"We need to look for fairly abundant methane and carbon dioxide on a world that has liquid water at its surface, and find an absence of carbon monoxide," said co-author David Catling, a UW professor of Earth and space sciences. "Our study shows that this combination would be a compelling sign of life. What's exciting is that our suggestion is doable, and may lead to the historic discovery of an extraterrestrial biosphere in the not-too-distant future."
Also at Popular Mechanics.
Disequilibrium biosignatures over Earth history and implications for detecting exoplanet life (open, DOI: 10.1126/sciadv.aao5747) (DX)
(Score: 1) by tftp on Friday January 26 2018, @04:53AM (4 children)
(Score: 4, Insightful) by bzipitidoo on Friday January 26 2018, @06:21AM (2 children)
This isn't looking for civilization, it's looking for life. On Earth, civilization has existed for 0.000005 billion years, while life had been around for 4 billion years. We're far more likely to find a world full of alien microscopic life than an alien civilization.
Futile? Not at all. Just because we have not detected any life anywhere else in our solar system is no reason to despair of ever finding any. We've hardly had a chance to look yet, and the sample size in our own solar system is very, very small. It's been only 25 years that we've known for sure that there are even exoplanets! Before the discovery of 51 Pegasi b, some wondered if having planets in orbit was very rare or even unique. We'll be taking a closer look, be sure of that. And what we may find is that life is everywhere. I would not be the least surprised if 1 in 10 stars or more is host to a planet with alien bacterial life. I suspect we underestimate (underguestimate?) because we are prejudiced and like to think we and our planet are so special.
(Score: 1, Informative) by Anonymous Coward on Friday January 26 2018, @08:36AM (1 child)
You completely missed his point. It's not about civilizations or the probability of finding life, it's about that the life we are looking for is earth-based life.
For example, looking for the lack of carbon monoxide. Carbon monoxide is poisonous to earth-based life, at least oxygen-breathing earth-based life. It won't be poisonous to a carbon monoxide breathing alien life form, or one that doesn't breathe in the first place.
And that's just carbon-based life. Who knows what silicon-based life looks like.
(Score: 2) by takyon on Friday January 26 2018, @09:28AM
Let's look for what will be the easiest to recognize. If unusual forms of life are common within the nearest thousand light years, it can wait another ten years for the data to be analyzed.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2, Interesting) by khallow on Friday January 26 2018, @07:35PM