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To say "they had not done the preliminary work of understanding the inorganic chemistry of [Venus]" seems uncharitable, in this case. IIUC, the original paper

To say "they had not done the preliminary work of understanding the inorganic chemistry of [Venus]" seems uncharitable, in this case. IIUC, the original paper is exactly an attempt to do that work, and the discussion in this blog post recognizes plenty of possibilities other than life.

wahern 6y ago
Those Mars papers weren't necessarily any less rigorous. In context, I take "preliminary work of understanding the inorganic chemistry" to imply something like in situ sampling and analysis, which in some of the Mars cases revealed new geology, or at least hypotheses which were considered extremely unlikely given contemporary understanding--understanding that also included satellite imagery and other cutting edge remote sensing--were catapulted into hard fact shortly after the Exploration rovers landing. The paper covers its butt with qualifications like, "Even if confirmed, we emphasize that the detection of PH3 is not robust evidence for life, only for anomalous and unexplained chemistry." But the overall emphasis of the paper is rather optimistic, to say the least, very much like prior claims regarding Mars' chemistry and geology. IMO, arguably we know far more about biological chemistry than we do about geology even on Earth. Even when we have a solid idea of the boundaries of what's geologically possible and impossible, we aren't nearly as knowledgable in terms of being able to order the possibilities in terms of relative likelihood. The Chicxulub impact and its effects were only confirmed within the lifetimes of most people on HN, for almost any reasonable value of confirmed--1990s, 2016 drilling, w'ever. We were already well along on our way to understanding the detailed chemistry of DNA before even the general concept of plate tectonics (let alone the finer details) became established scientific fact. Studies from the 2015 Mercury MESSENGER impact have overturned and are continuing to overturn established consensus on planetary geology. We should be skeptical of claims (implicit or explicit) regarding the relative likelihood of biologic vs non-biologic processes. OTOH, perhaps governments aren't apt to fund those experiments without the enticement. Extravagant claims are useful to help make that happen, and either this group had that in mind or it's simply the case that we only ever hear about such studies when they do make extravagant claims. Either way, I would certainly support more Venusian missions even if my money is in history repeating itself--new geology, not new life.

wahern 6y ago

Those Mars papers weren't necessarily any less rigorous. In context, I take "preliminary work of understanding the inorganic chemistry" to imply something like in situ sampling and analysis, which in some of the Mars cases revealed new geology, or at least hypotheses which were considered extremely unlikely given contemporary understanding--understanding that also included satellite imagery and other cutting edge remote sensing--were catapulted into hard fact shortly after the Exploration rovers landing. The paper covers its butt with qualifications like, "Even if confirmed, we emphasize that the detection of PH3 is not robust evidence for life, only for anomalous and unexplained chemistry." But the overall emphasis of the paper is rather optimistic, to say the least, very much like prior claims regarding Mars' chemistry and geology. IMO, arguably we know far more about biological chemistry than we do about geology even on Earth. Even when we have a solid idea of the boundaries of what's geologically possible and impossible, we aren't nearly as knowledgable in terms of being able to order the possibilities in terms of relative likelihood. The Chicxulub impact and its effects were only confirmed within the lifetimes of most people on HN, for almost any reasonable value of confirmed--1990s, 2016 drilling, w'ever. We were already well along on our way to understanding the detailed chemistry of DNA before even the general concept of plate tectonics (let alone the finer details) became established scientific fact. Studies from the 2015 Mercury MESSENGER impact have overturned and are continuing to overturn established consensus on planetary geology. We should be skeptical of claims (implicit or explicit) regarding the relative likelihood of biologic vs non-biologic processes. OTOH, perhaps governments aren't apt to fund those experiments without the enticement. Extravagant claims are useful to help make that happen, and either this group had that in mind or it's simply the case that we only ever hear about such studies when they do make extravagant claims. Either way, I would certainly support more Venusian missions even if my money is in history repeating itself--new geology, not new life.