Big astronomy announcement coming up

Something big is brewing in the world of astronomy, and will be published soon, but it’s heavily embargoed, and so every time it’s mentioned it gets taken down, like the video in the second tweet below. One possibility is that they’ve discovered “signs of life” on Venus, in the form of phosphine in the atomosphere, a gas (PH3) that on Earth has only a biogenic origin. But this is Venus, Jake!

Word on the street is that there will be a Big Announcement tomorrow. There’s been recent speculation that microbial life could survive in the atmosphere above Venus, but we would only be able to see the compounds there, and who knows how phosphene could be formed—if it is phosphine. But the news may be something quite different.

Anyway, does anybody know what this is about? I’m very curious.

78 Comments

  1. John Donohue
    Posted September 13, 2020 at 12:19 pm | Permalink

    In the past week, the buzz has been around destruction of the entire “dark matter/dark energy” worldview, due to new findings from Hubble images.

    • alan
      Posted September 13, 2020 at 12:38 pm | Permalink

      I hope so! I’ve never liked the dark stuff. I’ve always felt dark energy and matter are the modern version of epicycles to explain Mars’ retrograde motion.

      • Torbjörn Larsson
        Posted September 13, 2020 at 6:02 pm | Permalink

        So you put personal opinion and philosophic models of science above the facts and science? Most physicists agree that our universe is a Lambda-Cold Dark Matter one [Lambda for the dark, vacuum, energy], as noted in say Wikipedia. Even inflation, which works in the same manner as dark energy, is now noted as so tested that it is the majority view.

        The context here may be the history of neutrinos and black holes, which also were long unevidenced or debatable (weak interactions). But I note that when dark matter and dark energy was observed, the “not that” opinion dropped the then still ongoing “not that” opinion on black holes.

        As our host often notes, “so it goes”.

        • Torbjörn Larsson
          Posted September 13, 2020 at 6:03 pm | Permalink

          “Not that” was doubled, strike the 2nd one.

        • Posted September 14, 2020 at 2:55 am | Permalink

          So you put personal opinion and philosophic models of science above the facts and science?

          I don’t know how you got that idea from the parent post. Not liking something is not the same as not accepting it.

          To me, as a non physicist, dark energy is deeply unsatisfying as an explanation of the accelerating expansion of the Universe seeing as it’s really just a magic number added on to an equation to make it describe what we actually see.

          Dark matter is also irritating but is not as bad, seeing as it is just stuff we can’t see yet. The only thing I don’t like about dark matter is the way woo merchants use it to bash rational people over the head: “95% of the Universe is invisible to us, how can you say telepathy/reiki/dowsing etc etc is not real”.

          • Torbjörn Larsson
            Posted September 14, 2020 at 6:45 am | Permalink

            I was responding to “I never liked … felt” and the absence of objective evidence context.

            I am sorry that you confuse math – where you can freely add placeholder terms – with physics where you can’t. But that is anyway not a problem for LCDM, obviously, albeit it is fashionable in popular media to describe it thusly. Neither is the fashionable bait-and-switch between “see” and observe – dark matter has been observed by many independent means and they all agree on the observation. Cosmic background spectra is the obvious starting point, since you yourself can easily identify the dark matter dominated peaks and the physics behind.

            Dark energy is obviously then not “a … number” as seen from the above, it has a physics – it is identifiable as vacuum energy. Dark energy *on its own* was observed to 8 sigma in the recent BOSS galaxy survey cosmological paper. (And the entire LCDM was pushed down to 1 % uncertainty in all its predictions.) You don’t expect an 8 sigma observation to change (or be described as just a “number”). If you have quantum field theory – and we have – you expect the vacuum ground state to have an energy density. Which is what we now have found.

            Dark matter is heavy, gravitationally interacting particles from yet another quantum particle field that hasn’t got a name yet. Nobody expected that before the 30s, but it turns out that, like with the low value of dark energy observed, the universe wouldn’t be habitable without it. There would be few if any stars if dark matter didn’t exist, no structure formation starting from the cosmic gas filaments over galaxy clusters and galaxies down to stars.

            I don’t see that you said anything different from alan, but I hope I have clarified some of the confusion.

            • Posted September 14, 2020 at 7:31 am | Permalink

              The point is (and this I meant to put in my previous post but forgot and it does render my previous post a bit pointless) that just because something is true, you don’t have to like it and just because you don’t like something does not mean you are denying its truth.

              Your previous post inferred something about alan’s beliefs that wasn’t in his post.

              By the way, I know what dark energy and dark matter are. You didn’t need to explain them again. The fact is that they are both placeholders for physical observations we can’t explain using current models (or without tweaking current models). You may be philosophically satisfied that 95% of the Universe is invisible to us, but I’m not.

    • rickflick
      Posted September 13, 2020 at 1:40 pm | Permalink

      Hubble was supposed to be cancelled years ago. Good thing they kept it going.

    • Posted September 13, 2020 at 2:42 pm | Permalink

      Pretty unlikely. There’s no way any one set of observations could falsify those. You’d need whole sets of observations covering a range of topics, along with a multi-year debate about the interpretation.

      • John Donohue
        Posted September 13, 2020 at 2:49 pm | Permalink

        Coel, did you watch that very sequence when dark matter and dark energy “became a thing?”

        It was rapid and dubiously ad hoc.

        • Posted September 13, 2020 at 2:54 pm | Permalink

          Dark matter “became a thing” over a 20- or 30-yr period as evidence gradually accumulated, and as alternative explanations for the observations became gradually less tenable.

          Dark energy was much later, and yes the acceptance of that was relatively rapid, but that’s because it solved several outstanding problems in cosmology all in one go. So several independent lines of evidence then pointed to it. It wasn’t at all ad hoc.

          • Torbjörn Larsson
            Posted September 13, 2020 at 6:13 pm | Permalink

            It is the criticism, and too often the putative “alternatives” that are ad hoc. C.f. the now effectively dead “MOND gravity” [ https://www.quantamagazine.org/troubled-times-for-alternatives-to-einsteins-theory-of-gravity-20180430/ ]. Which after 2015 – when CDM started to explain galaxies better than any alternative due to including gas feedback (such as supernovas and jets) – was failing in its own narrow sector.

            Of course, upheavals can happen, even if there are no realistic alternatives any longer. But that would be one unlikely event today. Dark energy *on its own* was observed to 8 sigma in the recent BOSS galaxy survey cosmological paper, and the entire LCDM was pushed down to 1 % uncertainty in all its predictions.

            I don’t know of any other area where an 8 sigma observation is seen as dubious and/or “ad hoc” The absolute lack of evidence when making such opinion is also jarring.

    • Posted September 13, 2020 at 3:22 pm | Permalink

      I’ve got a whole lecture coming up about the origin and evolution of the universe, and in it dark matter and dark energy play a significant part. I would not be happy if they “cancel” d.m. and d.e. since I’ve invested a lot of time describing the big picture around … whatever they are.

    • Torbjörn Larsson
      Posted September 13, 2020 at 5:53 pm | Permalink

      That sounds like wishful thinking, amplified with the press release of a recent finding of large galaxy clusters (with thousand of galaxies) where individual small halos produce gravitational lensing effects an order of magnitude stronger than expected. An example of press release click bait title: “Hubble’s Shocking Dark Matter Discovery: Observations Suggest a Missing Ingredient in Cosmic Recipe” [SciTechDaily].

      we know little about the infall dynamics of these extreme system with additional gas and galaxies streaming along the connecting cosmic gas filaments and ramming into the resulting mess. The paper itself lists four previous cases of such narrow discrepancies and note that they have all been solved – the “missing satellite”, “cusp-core”, “too-big-to-fail” discrepancies as well as discrepancies with planes of satellite galaxies. As I remember it all those discrepancies had resolutions in the baryonic matter sector.

      And it didn’t take long for a new press rlease offering two correlations that explain either end of extreme objects in these clusters. “Astronomers have found that the key to understanding galaxies with “extreme” sizes, either small or large, may lie in their surroundings. In two related studies, an international team found that galaxies that are either “ultra-compact” or “ultra-diffuse” relative to normal galaxies of comparable brightness appear to reside in dense environments, i.e., regions that contain large numbers of galaxies. This has led the team to speculate that these “extreme” objects could have started out resembling normal galaxies, but then evolved to have unusual sizes through interactions with other galaxies.”

      [ https://disq.us/url?url=https%3A%2F%2Fphys.org%2Fnews%2F2020-09-galactic-census-reveals-extreme-galaxies.html%3AYG2H4YsTZzM4ide-krb7sOQghlM&cuid=653846 ; the article links to two papers those abstracts support the claim of correlations to a massive cluster center.]

      Besides explaining more of ultra-diffuse galaxies, the ultra-compact halos distribution may be valuable in this context.

    • Taz
      Posted September 13, 2020 at 5:54 pm | Permalink

      Maybe they’re announcing that from now on it will be written as Dark matter and Dark energy.

      • grasshopper
        Posted September 13, 2020 at 7:05 pm | Permalink

        Does it really matter matter matter? A parody is waiting to be written.

      • Diana MacPherson
        Posted September 13, 2020 at 8:35 pm | Permalink

        Or that we can’t use the word “dark” because it seems racist so we’re going to use emojis instead: 🧐⚡️🧐🙌

        • rickflick
          Posted September 13, 2020 at 8:42 pm | Permalink

          Ha. That’s funny.

  2. ThyroidPlanet
    Posted September 13, 2020 at 12:25 pm | Permalink

    Sub

  3. Alan Clark
    Posted September 13, 2020 at 12:29 pm | Permalink

    In the UK, “The Sky at Night” on BBC4 on Monday 14th at 10:30 has a ‘special report’.

    • gravelinspector-Aidan
      Posted September 13, 2020 at 2:48 pm | Permalink

      … and indeed @ChrisLintott (for those unfamiliar, he’s been one of the science mainstays of Sky@Night for perhaps a quarter century ; professor of astronomy at somewhere, for a good few years now) has been hinting at something big for several days.
      Corollary : they’ve known about it for several months, in order to get the timetable changed, and I recall that early in the COVID crisis there were mentions of jetting off to film for “something big”.
      [Bzzzzzz bzzzzz] sound of excitement.

  4. J Cook
    Posted September 13, 2020 at 12:40 pm | Permalink

    Maybe something about those mysterious objects the Navy pilots Have been scoping on their radars off the Southern California and Baja coast.

    • gravelinspector-Aidan
      Posted September 13, 2020 at 2:49 pm | Permalink

      Nope, that would be astronautics, not astronomy.

  5. David Harper
    Posted September 13, 2020 at 12:42 pm | Permalink

    Phosphine has been observed in interstellar space, so if it’s been detected in the atmosphere of Venus, it’s most likely of non-biological origin. There’s a surprising amount of chemistry going on in space, particularly in interstellar gas clouds. Indeed, there’s an entire branch of astronomy called astrochemistry devoted to it.

    And, as PCC(E) notes, this is Venus, the Solar System’s very own vision of Dante’s Inferno. Its atmosphere has no measurable amounts of water, and if water did once exist on the surface of Venus, it vanished four billion years ago, along with any signs of life.

    • gravelinspector-Aidan
      Posted September 13, 2020 at 3:11 pm | Permalink

      Didn’t 1950s scientists detect water absorbtion lines in the spectrum of Venus, by reflection, away back when, fuelling the “swamp world” so beloved of SF until we actually started putting probes down into the atmosphere. They knew it was there, even if they couldn’t quantify it very well.
      As I recall, the water content of Venus’ atmosphere varies by a couple of orders of magnitude with altitude, to the point that the behaviour of water is one of the constraints on building models of Venus’ climate.
      Checking the Wiki page, they cite 20ppm for the water content, from a 2005 “NASA fact sheet” ; that is, for comparison, about 10 times the methane content of mean northern hemisphere Earth (which measurement I used to perform function checks on hydrocarbon analysers at work).

    • Torbjörn Larsson
      Posted September 13, 2020 at 6:28 pm | Permalink

      Modern models do allow for oceans on Venus up until recently [ http://astrobiology.com/2020/09/on-the-possible-evolutionary-history-of-the-water-ocean-on-venus.html ], and observations have also showed signs of ongoing mantle plume activity [“Likely active volcanoes found on Venus, defying theory of dormant planet”, Guardian], all reminding or its similarity with Earth.

      “Under this model, it has the possibility that the habitable zone could include Venus. It could continue for ∼1 Gy in faint young solar flux increasing, with modest parameters such as albedo = 0.3, relative humidity (RH=1), and pn0=105Pa.

      If we relax parameters considering the 3-Dimensional calculations*, the ocean could exist there longer than ∼ 4.6 Gy. In such cases, we have to consider the cause of runaway other than just solar luminosity increasing.”

      The cloud layer where scientists claim to see micrometer sized unknown absorbers is claimed to have habitable heat, pressure and acidity [“Life on Venus”, Wikipedia.]. “Although there is little possibility of existing life near the surface of Venus, the altitudes about 50 km (31 mi) above the surface have a mild temperature, and hence there are still some opinions in favor of such a possibility in the atmosphere of Venus.” The model of putative extant life is often having prokaryotes lofted to these heights before the end of the greenhouse runaway, now living on the acidic atmosphere redox potentials.

      *The change from 1D to 3D models have had a huge impact on habitability zone models, as far as I can see. Also tidally locked planets are much more “agreeable” in them.

    • grasshopper
      Posted September 13, 2020 at 9:16 pm | Permalink

      If phosphine exhibits chirality, perhaps there is an anomalous ratio between the levo and dextro forms on Venus.

  6. Posted September 13, 2020 at 12:43 pm | Permalink

    sub

  7. procatsitter
    Posted September 13, 2020 at 12:44 pm | Permalink

    sub

  8. Posted September 13, 2020 at 12:47 pm | Permalink

    Will the divisiveness never end? They’re pitting Venus against Mars now as most interesting planet. Mars is already the Red Planet so that makes Venus the Blue Planet, I guess.

    • enl
      Posted September 13, 2020 at 1:04 pm | Permalink

      Wait…. I thought mars was the red planet because it is a card carrying member of the communist party.

      • jezgrove
        Posted September 13, 2020 at 3:01 pm | Permalink

        Maybe it’s the red planet because it’s behind the Trump re-election campaign? (It’s confusing for us Brits, where the “red” party is on the left and the “blue” party is on the right, though given Putin/Trump maybe you guys have it the correct way round? On the other hand, the Conservative Party in the UK is the recipient of loads of Russian dosh, so maybe not…)

      • gravelinspector-Aidan
        Posted September 13, 2020 at 3:13 pm | Permalink

        Only if you’re a Kim Stanley Robinson fan.

    • Posted September 13, 2020 at 12:51 pm | Permalink

      I’m betting it’s about life on Venus.

      • Posted September 13, 2020 at 12:59 pm | Permalink

        Makes sense but if it is just discovery of the presence of some compound associated with life on Earth, it may turn out to be nothing in the end. With the exotic conditions that exist in the atmosphere in Venus, it seems more likely that we’ll discover a new process by which the compound can be created without the involvement of life.

        • David Harper
          Posted September 13, 2020 at 1:26 pm | Permalink

          Many simple molecules exist in interstellar space, including phosphine. They were created by non-biological processes; see my comment #5 above.

        • Torbjörn Larsson
          Posted September 13, 2020 at 6:34 pm | Permalink

          I think everyone agree that finding extinct or extant life on other planets within the system is a matter of sample return. Current methods of eliminating confounds in prokaryotes or such fossils demand microscale analysis [even for stromatolites and MISS].

          And outside the system it will come down to either statistics or observing an atmosphere that is in too much thermodynamical imbalance to be caused by anything else (if one can eliminate volcanism and other such confounds).

    • Posted September 13, 2020 at 3:26 pm | Permalink

      Could just be disinformation, aimed at throwing people off the trail.
      I’m not saying its aliens, but…

    • Posted September 13, 2020 at 9:51 pm | Permalink

      I think you’re on the right track, Lou. The news might be definitive proof of water droplets in the upper atmosphere. That’ll do.

  9. Ken Kukec
    Posted September 13, 2020 at 1:05 pm | Permalink

    If word on the street is right, I reckon the $64,000 question (adjusted for inflation) is whether the life on Venus represents “Genesis II” or transmigrated from/to life on Earth.

    If the former, it would suggest that life is prevalent throughout the universe.

    • Diana MacPherson
      Posted September 13, 2020 at 1:12 pm | Permalink

      If you’re a The Expanse fan, perhaps it’s the protomolecule.

    • rickflick
      Posted September 13, 2020 at 1:45 pm | Permalink

      $64,000 in 1955 (when the game show first aired)
      is now worth $620,699.70.

    • gravelinspector-Aidan
      Posted September 13, 2020 at 3:18 pm | Permalink

      We’d really need sample return to be sure it’s “Genesis 2.0” versus panspermia (hawk, spit, the word leaves a bad taste in the mouth).
      What would you need? A genetic system which is definitely not RNA/ DNA. A “PNA” would really set the panspermia pigeons pecking at the cats of abiogenesis. Left-hand-thread proteins, and a different set of amino acids would be … not decisive (but divisive? oh yeah!)

      • Ken Kukec
        Posted September 13, 2020 at 7:07 pm | Permalink

        “Genesis 2.0” — you mean after Peter Gabriel left the band and Phil Collins took over front-man duties? 🙂

  10. merilee
    Posted September 13, 2020 at 1:15 pm | Permalink

    Let’s hope it’s not like one of Trump’s announcements…

    • Posted September 13, 2020 at 2:22 pm | Permalink

      Well, the scientists have been looking very strongly at Venus for a long time now. I think we’ll have something by Tuesday of next week. But we’ll see what happens.

      • Ken Kukec
        Posted September 13, 2020 at 2:53 pm | Permalink

        Jimmy Clanton used to look at Venus very strongly for a long time, too:

        • merilee
          Posted September 13, 2020 at 3:31 pm | Permalink

          Thanks for the earworm😬 Mona Lisa in a ponytail…

  11. Eli Siegel
    Posted September 13, 2020 at 1:17 pm | Permalink

    I remember the evidence for life in meteorites originating from Mars.

    • tjeales
      Posted September 13, 2020 at 8:33 pm | Permalink

      Wasn’t the last big build up to a disappointing announcement the infamous “arsenic life” paper?

  12. Posted September 13, 2020 at 1:23 pm | Permalink

    Given this miserable year, it could be an announcement that a large asteroid is headed our way.

    • gravelinspector-Aidan
      Posted September 13, 2020 at 3:20 pm | Permalink

      MPML (Minor Planets Mailing List, where a lot of the serious astrometry and orbital calculation people hang out) has had normal levels of busy-ness for weeks.

    • Posted September 13, 2020 at 3:30 pm | Permalink

      Uh, there is an asteroid heading our way. And it passes very close the day before the election. Last I read the odds of it hitting us is not zero.

      • merilee
        Posted September 13, 2020 at 3:41 pm | Permalink

        Aimed at Mar-a-Lago?

      • Posted September 13, 2020 at 3:53 pm | Permalink

        Hmmm. What would be worse? An asteroid hitting earth on November 2 or tRump winning a second term on November 3?

  13. Really Outthere
    Posted September 13, 2020 at 1:41 pm | Permalink

    Can confirm that it’s phosphine in the Venusian atmosphere. Folks at Cardiff University have been working on that. They do NOT conclude that it is biological in origin.

  14. Posted September 13, 2020 at 2:01 pm | Permalink

    Unofficially, I have heard that tomorrow Walter Reed Hospital will announce proof that tRump is actually a reptilian humanoid from the star system Alpha Draconis.

    • gravelinspector-Aidan
      Posted September 13, 2020 at 3:25 pm | Permalink

      At 300-odd light years, their detection of Ben Franklin’s experiments with lightning and Volta applying it to re-animating Mary Shelly … they must have had the launch system ready to go as soon as the … oops …
      Sorry, not Franklin and Shelly. Martin Luther? Or Gutenberg, is that closer to the line?

  15. Filippo
    Posted September 13, 2020 at 2:48 pm | Permalink

    I look forward to (actually brace myself for) the NY Times article about it. Maybe there will be the headline, “Is There Life on Venus?”. Will see if the reportage includes “could” or “might” be life on Venus. Reasonably likely to see the locution “It is unclear . . . .” Or, “presence of phosphine suggests the possibility of life . . . .”

    Will see if NYT faithfully and completely report astronomers’ statements of fact, and resists the urge to give short shrift to non-biological creation of phosphine. Reasonably likely an “ugh” – inducing, fatuous introductory paragraph or two to slog through.

    (Apologies for my mean streak venting. But one sees such reportage in the Times all too frequently. Hope my prediction is wrong.)

  16. Posted September 13, 2020 at 3:32 pm | Permalink

    If they find phosphene on Uranus then the jokes will be predictable.

    • Steve Pollard
      Posted September 13, 2020 at 4:36 pm | Permalink

      ‘Is there life on Uranus?’

      ‘No, but there may be on your Mars’.

  17. Jimbo
    Posted September 13, 2020 at 5:09 pm | Permalink

    Please, not ‘PH3 over Venus = evidence of life.’
    I can’t stand specious claims like this. Even if true, it is not evidence of life in the least, it is evidence for an extraordinarily simple molecule in our solar system. Phosphine is simply a reduced form of the element phosphorus (as opposed to phosphate) and phosphorus is common in our solar system being the 12th most abundant element in Earth’s crust. [yawn]
    We’ve been here before: a Martian meteorite with fossilized bacteria, arsenate replacing a phosphate in DNA as a “new form of life,” etc.

    It rains 800C sulfuric acid on Venus. I know, I know the clouds above…yada yada. There are clouds above Jupiter too. I am pretty sure neither contains life and further, I am deeply skeptical of cosmologists’ claims of life being common throughtout the universe. I think it is exceedingly rare.

  18. Posted September 13, 2020 at 5:34 pm | Permalink

    PH3 is a biosignature gas when searching possible habitable exoplanets because there is no known abiotic source for temperate environments. But Venus is anything but temperate. At high temperatures, PH3 can be prepared chemically.

    • Jimvo
      Posted September 13, 2020 at 7:01 pm | Permalink

      Thank you!
      While I am no fan of Occam’s Razor, I think an aspect of it applies here: what’s more probable, that phosphine gas observed above Venus is being produced by cloudborne* organisms and accumulating enough to be observed or that a chemical or photochemical process (maybe never before seen) is what’s producing it? Surely life is the least likely explanation given that chemistry happens under all kinds of conditions whereas those conducive to life are more narrowly bounded.

      *Can we agree that the 800 degree surface temp of Venus is sterilizing? Carbon-carbon bonds break at lower temps.

  19. W.Benson
    Posted September 13, 2020 at 5:52 pm | Permalink

    Astronomers work so so hard to confirm the existence of life beyond the confines of earth. It seems like some kind of cult prophesy or mental illness.

  20. Posted September 13, 2020 at 6:27 pm | Permalink

    If it is Venus, Sagan predicted life in the clouds… & maybe a Russian scientist whose name I have forgotten…

  21. Posted September 13, 2020 at 6:40 pm | Permalink

    I haven’t heard anything about this, but will look forward tom hearing about it if it’s announced. Evidence of any form of life existing anywhere but on Earth would definitely be big news!

  22. Torbjörn Larsson
    Posted September 14, 2020 at 6:24 am | Permalink

    UPDATE: Smokedpaprika already linked to this [ http://astrobiology.com/2020/09/phosphine-detected-in-the-atmosphere-of-venus—an-indicator-of-possible-life.html ], but there has been update with the missing video, which explains that:

    – “The press release has been issued in advance to some journalists under embargo – but not others (like us). We have not seen the press release.”

    – “Its presence suggests – suggests – some strange chemistry going on since phosphine is something you’d only expect to see if life (as we know it) was involved.”

    – “From what we’re told the researchers have concluded that abiotic mechanisms (i.e. ones that do not involve life) that might produce phosphine cannot account for the large amount that they have detected. The phosphine has been detected in the region within the atmosphere of Venus that is considered by some to be potentially habitable. As to what spin the researchers put on this, we’ll have to wait for reporters who have the press release or are allowed to participate in the Zoom press conference thing tomorrow at 15:00 GMT to let us know.”

    I don’t know about terrestrial planet geochemistry of phosphine discussed in the video, but there is a difference between enough signal for detection and enough signal to exclude putative confounds. The article title seems fitting: “Phosphine Detected In The Atmosphere of Venus – An Indicator of Possible Life?” I guess we have to wait for the press conference and how this plays out (such as a dedicated balloon mission with or without sample return capabilities).

  23. Torbjörn Larsson
    Posted September 14, 2020 at 7:12 am | Permalink

    Doing some quick browsing, I note that phosphine is regularly produced everywhere there is fosfor and heat, so volcanism and meteorites are common suspects [ https://www.pnas.org/content/105/3/853 ].

    “Phosphine as a Biosignature Gas in Exoplanet
    Atmospheres”, arxiv 1910.05224, Sousa-Silva et al., notes that it is seen in stars or gas giant atmospheres (not our own gas giants, funnily enough). It puts the thermodynamic condition for rocky planets to have extensive abiotic phosphine when atmospheres is > 800 K and > 0.1 bar.

    Venus is at a mean surface temperature of > 735 K and a surface pressure of 92 bar, and as I linked in another comment is now known to have extensive, likely active volcano activity. “In 2008 and 2009, the first direct evidence for ongoing volcanism was observed by Venus Express, in the form of four transient localized infrared hot spots within the rift zone Ganis Chasma,[47][n 1] near the shield volcano Maat Mons. Three of the spots were observed in more than one successive orbit. These spots are thought to represent lava freshly released by volcanic eruptions.[48][49] The actual temperatures are not known, because the size of the hot spots could not be measured, but are likely to have been in the 800–1,100 K (527–827 °C; 980–1,520 °F) range, relative to a normal temperature of 740 K (467 °C; 872 °F).[50]” [Wikipedia]

    YMMV obviously, but I’m less enthusiastic compared to before browsing phosphine geochemistry and Venus conditions.

  24. Torbjörn Larsson
    Posted September 14, 2020 at 10:29 am | Permalink

    Well.

    The paper is out in Nature Astronomy [“Phosphine gas in the cloud decks of Venus”] (among them with Sosua-Silva as coauthor), and takes the tack that they see too much phosphine.

    Single-line millimetre-waveband spectral detections (quality up to ~15σ) from the JCMT and ALMA telescopes have no other plausible identification. Atmospheric PH3 at ~20 ppb abundance is inferred. The presence of PH3 is unexplained after exhaustive study of steady-state chemistry and photochemical pathways, with no currently known abiotic production routes in Venus’s atmosphere, clouds, surface and subsurface, or from lightning, volcanic or meteoritic delivery. PH3 could originate from unknown photochemistry or geochemistry, or, by analogy with biological production of PH3 on Earth, from the presence of life.”

    [A video from the press briefing is posted on Astronomy Now.]

    Guardian has some reactions [ https://www.theguardian.com/science/2020/sep/14/scientists-find-gas-linked-to-life-in-atmosphere-of-venus ]:

    To generate the amount of phosphine observed, Earth microbes would need to work at only 10% of their maximum productivity, the scientists say.

    Sara Seager, a planetary scientist on the study at MIT in the US, called the finding “mind-boggling”. She hypothesises a lifecycle for Venusian microbes that rain down, dry out and are swept back up to more temperate altitudes by currents in the atmosphere.

    Charles Cockell, an astrobiologist at the University of Edinburgh, said that, rather than hinting at life on Venus, the work raises questions about phosphine as a “biomarker”.

    “A biological explanation should always be the explanation of last resort and there are good reasons to think the Venusian clouds are dead. The concentrations of sulphuric acid in those clouds are more extreme than any known habitat on Earth,” he said.

    Lewis Dartnell, an astrobiologist at the University of Westminster, said the findings would spur more work. “This is a huge opportunity for follow-on observations from Earth-based telescopes, and ideally to scrutinise these droplets in the Venusian atmosphere with a balloon probe drifting through the acidic clouds.”

    Seems there here are possible confounds, as expected.

    (And also possibly too much sulphuric acid, as a posterior.)

    • rickflick
      Posted September 14, 2020 at 2:17 pm | Permalink

      How can you rule out chemical sources from this distance. I suspect:

      “..rather than hinting at life on Venus, the work raises questions about phosphine as a “biomarker”.”

      But, it might generate some additional funding for exobiology.


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