From their results: More likely is that many of the planets orbiting M-dwarf stars to have very thin or possible no atmospheres. In both cases, life forming in such systems appears less likely than previously believed.
He ends with, “The ancient question ‘Are we alone?’ has graduated from being a philosophical musing to a testable hypothesis. We should be prepared for an answer.” It’s worth asking another question: What if, after decades of research, no answer comes? What would that change?
The fundamental problem is still the same: It is very difficult to extrapolate from a sample of one instance of life. Suppose we had information on tens of thousands of exoplanets, thousands of which had life. Making the reasonable assumption that a pattern develops within this data, we could then give fairly reliable odds on a given planet having life if its relevant data are known. But we don’t have any of this. It’s all a dreamscape.
Wherever you thought you were on that planet, you would soon be somewhere else. But it’s not really anywhere, is it? Advice: Stay home on solid Earth.
This means that the search for extraterrestrial life should focus on planets with strong magnetic fields. Meanwhile, why is it that a thousand coincidences pointing in the same direction never seem to add up to a pattern, just something to explain away?
Okay but now one question: If none of those 47 planets has life, does that count as evidence against the proposition that “We Are Not Alone”? Does anything count as evidence against the proposition?
From Universe Today: In addition, research into how life evolved on Earth has shown that water alone does not guarantee life – nor, for that matter, does the presence of oxygen gas.
Well, in fairness, failing to treat them respectfully is one sin we can safely say we haven’t committed; we have never encountered an alien ecosystem.
It turns out that other solar systems are not shedding much light on how ours came to be: But as the menagerie of young planetary systems grows, researchers are struggling to square their observations with current theories on how our Solar System and others formed. Such ideas have been in turmoil ever since astronomers started […]
That’s a common problem when we ask great figures their opinion about things they haven’t studied. From a review of Stephen Hawking’s (1942–2018) last book (or the last book that could be put together plausibly under his name), Brief Answers to the Big Questions: Because of the likelihood of a nuclear confrontation or an environmental catastrophe, […]
An MIT astronomer is 75% certain that an object previously suspected of being an Intro of exomoon (a moon orbiting an exoplanets) really is that: The first confirmed detection of an exomoon would mark a milestone in exploring planetary systems throughout the Galaxy. It would, among other things, allow scientists to test ideas of moon […]
Suggested at New Scientist: There may be life out there that was like life on Earth when Earth was a very different environment: In the 4.5 billion years our planet has existed, it has experienced dramatic transformations: ice ages and warming periods, times when the atmosphere was impossible to breathe, when large areas were desert, […]
In other words, Earth doesn’t just “have water”; it is fine-tuned for life. We need to find exoplanets that are likewise fine-tuned.
Plus, a friend offers a reply. From ScienceDaily: There may be more habitable planets in the universe than we previously thought, according to Penn State geoscientists, who suggest that plate tectonics — long assumed to be a requirement for suitable conditions for life — are in fact not necessary. When searching for habitable planets or […]
From SETI’s Seth Shostak, who surely doesn’t welcome this news, at NBC: A recent paper by three researchers at the University of Oxford is throwing shade on those who feel confident that the cosmos is thick with extraterrestrials. … If we own up to the true extent of these uncertainties and do the requisite math, […]