III. Ecosmos: A Revolutionary Fertile, Habitable, Solar-Bioplanet, Incubator Lifescape

G. An Astrochemistry to Astrobiological Spontaneity

Ness, Melissa, et al. Galactic Doppelganger: The Chemical Similarity Among Field Stars and Among Stars with a Common Birth Origin. arXiv:1701.07829. A dozen scientists with postings in Germany, Chile, Italy, USA, UK, and the Vatican Observatory achieve a broad materiality analysis which finds a consistency between a range of Milky Way stellar objects. Once again, that collaborative, sapient humans on a minute orb can do this at all is incredible, and must have some cosmic significance it we might consider this.

We explore to which extent stars within Galactic disk open clusters resemble each other in the high-dimensional space of their photospheric element abundances, and contrast this with pairs of field stars. Our analysis is based on abundances for 20 elements, (Fe, C, N, O, Na, Mg, Al, Si, S, K, Ca, Ti, V, Mn, Ni, P, Cr, Co, Cu, Rb) homogeneously derived from APOGEE spectra. We consider 90 red giant stars in seven open clusters and find that most stars within a cluster have abundances in most elements that are indistinguishable from those of the other members, as expected for stellar birth siblings. Our analysis implies that 'chemical tagging' in the strict sense, identifying birth siblings for typical disk stars through their abundance similarity alone, will not work with such data. However, our approach shows that abundances have extremely valuable information for probabilistic chemo-orbital modeling and combined with velocities, we have identified new cluster members from the field. (Abstract excerpts)

Norris, Ray and Stootman, Frank, eds. Bioastronomy 2002: Life Among the Stars. San Francisco: Astronomical Society of the Pacific, 2004. Proceedings of an IAU symposium suitably held on Hamilton Island, Great Barrier Reef, Australia, in the locale of ancient stromatilite mats. An earthwide exploration of its solar, galactic and cosmic environs in subject areas of Extrasolar Planets, Planetary Science, Origins and Evolution of Life, Archea, SETI, Post SETI and Education and Outreach. Papers range from observational results to big picture visions of Simon Conway Morris, Jill Tarter and others.

Novotny, Oldrich, et al. Quantum State Selective Electron Recombination Studies Suggest Enhanced Abundance of Primordial HeH+. Science. 365/676, 2019. As worldwide collaborations reconstruct how the lively Universe and phenomenal human beings came to be, a 26 person team based at MPI Nuclear Physics, with other postings in the Czech Republic, Germany, Russia, and Israel, cite results from the new University of Heidelberg Cryogenic Storage Ring which provide the best evidence to date for this helium hydride ur-molecule at the very onset of life’s cosmic evolution. See also a commentary First Molecule Still Animates Astronomers by Stefano Bovino and Daniele Galli in the same issue, and Astrophysical Detection of the Helium Hydride Ion HeH+ by Rolf Gusten, et al in Nature (568/357, 2019). In later 2019, we wonder how it might finally become critically possible to realize that an innately organic, astrobiological milieu exists on its procreative own.

The epoch of first star formation in the early universe was dominated by simple atomic and molecular species consisting mainly of two elements: hydrogen and helium. Gaining insight into this constitutive era requires thorough understanding of molecular reactivity under primordial conditions. We used a cryogenic ion storage ring combined with a merged electron beam to measure state-specific rate coefficients of dissociative recombination, a process by which electrons destroy molecular ions. We found a dramatic decrease of the electron recombination rates for the lowest rotational states of HeH+, compared to previous measurements at room temperature. The reduced destruction of cold HeH+ translates into an enhanced abundance of this primordial molecule at redshifts of first star and galaxy formation. (Abstract)

Oberg, Karen and Edwin Bergin. Astrochemistry and Compositions of Planetary Systems. Physics Reports. October, 2020. In this epochal year, Harvard-Smithsonian Center and University of Michigan astrophysicists provide a comprehensive graphic survey which seems to have no limit as to the expanse, depth and quality that our sapient individual and worldwide cumulative intelligence can achieve. A typical section is Setting the Chemical Trajectory: Planet Formation Begins in Molecular Clouds, and a detailed image is Protoplanetary Disk Chemistry. By a philoSophia vista to allow a genesis uniVerse which exists on its own, we ought to wonder who are we phenomenal, microcosmic Earthlings to perform, unawares until now, this vital functional task of retrospective self-quantification, description, witness and affirm?

Planets form and obtain their compositions in disks of gas and dust around young stars. The chemical compositions of these planet-forming disks regulate all aspects of planetary compositions from bulk elemental inventories to access to water and reactive organics, i.e. a planet's hospitality to life and its chemical origins. In this review we present our current understanding of the chemical processes active in pre- and protostellar environments that set the initial conditions for the disk chemical processes that evolve during the first million years of planet formation.. (Abstract excerpt)

Ozturk, S. Furkan, et al. Origin of Biological Homochirality by Crystallization of an RNA Precursor. arXiv:2303.01394. Harvard University and MRC Laboratory of Molecular Biology, Cambridge, UK including Dimitar Sasselov and John Sunderland describe a breakthrough method to explain how this intrinsic organic status can plausibly occur across a fertile ecosmic milieu.

Homochirality is a signature of life on Earth yet its origins remain a puzzle. Achieving homochirality is essential for prebiotic networks capable of producing functional polymers like RNA and peptides. Here we studied the spin-selective crystallization of racemic ribo aminooxazoline (RAO) on magnetite surfaces to reach a high enantiomeric excess. Our work combines two features for vital homochirality: chiral symmetry-breaking and self-amplification by RAO conglomerate crystallization. (Excerpt)

Ozturk, S. Furkan, et al. Origin of Biological Homochirality by Crystallization of an RNA Precursor on a Magnetic Surface. arXiv:2303.0194. We cite thie entry by Harvard University and Cambridge MRC Laboratory of Molecular Biology, UK astrobiologists including Dimitar Sasselov to report an inherent way that living, evolving, beings seem meant to appear, evolve, and just now retrospectively turn in wonder to quantify how it all came to happen.

Homochirality is a signature of life on Earth which is essential for a high-yielding prebiotic network to produce functional polymers like ribonucleic acid (RNA) and peptides. However, a prebiotically plausible explanation has not yet been shown. Here we enlist the chiral-induced spin selectivity (CISS) effect so to establish a strong coupling between electron spin and molecular chirality and a way for breaking the chiral molecular symmetry by spin-selective processes. Magnetic surfaces can be templates for the enantioselective crystallization of chiral molecules. Our results demonstrate a prebiotically plausible way of achieving systems level homochirality from completely racemic starting materials. (Excerpt)

Paschek, Klaus, et al. Prebiotic Vitamin B3 Synthesis in Carbonaceous Planetesimals.. arXiv:2310.11433. MPI Astronomy and Ludwig Maximilian University biochemists propose a novel pathway by which the original vivifying milieu could give occasion to even this vital physiological biomolecule.

Aqueous chemistry within carbonaceous planetesimals is a fertile mode for synthesizing prebiotic organic matter. Here, we studied the formation of vitamin B3 as an important precursor of the coenzyme NAD(P)(H), which is essential for the metabolism of all life. We propose an empirical reaction mechanism that explains the synthesis of vitamin B3. It combines sugar precursors glyceraldehyde or dihydroxyacetone with the amino acids aspartic acid or asparagine in aqueous solution. The predicted vitamin B3 abundances resulting from this new pathway were compared with measured values in asteroids and meteorites. In sum, our model fits well into the complex network of chemical pathways active in this environment. (excerpt)

Pendleton, Yvonne and Jack Farmer. Life: A Cosmic Imperative? Sky & Telescope. July, 1997. Yes, by way of meteorite biochemistry and favorable chances for life in the solar system, especially on the moons of Jupiter.

It is quite possible that life will be shown to be a natural consequence of planetary evolution and ‘a cosmic imperative’ anywhere that habitable zones of liquid water are maintained for even short periods of geologic time. (47)

Pentsak, Evgeniy, et al. The Role of Acetylene in the Chemical Evolution of Carbon Complexity. arXiv:2405.01866. EP, Maria Murga and Valentine Ananikov, Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow astrochemists post a 118 page, 550 reference contribution which extensively quantifies the presence of C2H2 as a interstellar biomolecular precursor on a course toward life and evolution. In this instance also, catalytic agencies are seen as a prime driver. (I was once a combustion consultant with acetylene known as a highly reactive fuel gas, fire on earth and in the sky.) See also Torsion-rotational transitions in methanol as a probe of fundamental physical constants by J. S. Vorotyntseva and S. A. Levshakov at 2405.04542.

Acetylene, among the multitude of organic molecules discovered in space, plays a distinct role in the genesis of organic matter. Characterized by its unique balance of stability and reactivity, acetylene is the simplest unsaturated organic molecule known to have a triple bond and is one of the most prevalent organic molecules found across the Universe. This review discusses the formation and expansion of carbon skeletons involving acetylene from the origination of the first aromatic ring and nanosized carbon particles. A distinct focus is accorded to the recent research into catalytic processes involving acetylene molecules, which is a significant instrument in driving the evolution of cosmic carbon complexity. The insights garnered from this review underline the significance of acetylene in astrochemistry and potentially contribute to our understanding of the chemical evolution of the Universe. (Excerpt)

For instance, catalytic pathways for the formation of aromatic compounds in space environments are likely underexplored. Catalytic processes, encompassing crucial events such as the formation of aromatic compounds, could occur on the surfaces of comets, asteroids, planets, and interstellar dust grains, as corroborated by recent findings. We can anticipate more exciting discoveries in this area in the coming years. Our understanding of cosmic chemical processes will continue to broaden in the future. There is no doubt that missions such as the James Webb Space Telescope, the forthcoming Dragonfly spacecraft and the Jupiter Icy Moons Explorer will revolutionize our comprehension of the evolution of organic compounds in space. This approach will facilitate the precise quantification of how physical conditions influence organic transformations, thereby allowing us to track the evolution of acetylene and other organic molecules across various space environments. (78)

Piran, Tsvi, et al. Cosmic Explosions, Life in the Universe and the Cosmological Constant. arXiv:1508.01034. As a mid 2010s worldwide science flourishes, evident by prolific daily postings on sites like this, Israeli, Spanish, American, and Norwegian researchers evaluate how a sapient, observant species could naturally evolve in a somewhat inhospitable cosmos. As the quotes add, while Gamma-Rays are prevalent and lethal, it seems that along with a favorable solar system, the Milky Way galaxy is especially suitable for life and mind since its properties tend to minimize their effect.

Galactic Gamma-Ray Bursts (GRBs) are copious sources of gamma-rays that can pose a threat to complex life. Using recent determinations of their rate and the probability of GRBs causing massive extinction, we explore what type of universes are most likely to harbour advanced forms of life. For this purpose we use cosmological N-body simulations to determine at what time and for what value of the cosmological constant (Λ) the chances of life being unaffected by cosmic explosions are maximised. We find that Λ−dominated universes favour the survival of life against GRBs. Within a ΛCDM cosmology, the parameters that govern the likelihood of life survival to GRBs are dictated by the value of Λ and the age of the Universe. We find that we seem to live in a favorable point in this parameter phase space which minimises the exposure to cosmic explosions, yet maximises the number of main sequence (hydrogen-burning) stars around which advanced life forms can exist. (Abstract)

In order for GRBs not to be life threatening, one has to live in a large, old, galaxy like the Milky Way that has undergone sufficient chemical evolution and its average metallicity is relatively large reducing the GRB rate. Furthermore, the outskirts of our galactic disk are sufficiently massive to harbour planetary systems that can support life, while not being very dense or dominated by star forming regions. Furthermore, for the Milky Way, extragalactic events are not dangerous as nearby GRB- hosting galaxies are far enough that even their strongest GRBs won't affect life on Earth. In other words, the Milky Way and its location is somewhat peculiar: it is a large, old galaxy and it is relatively isolated. (1)

The ΛCDM (Lambda cold dark matter) or Lambda-CDM model is a parametrization of the Big Bang cosmological model in which the universe contains a cosmological constant, denoted by Lambda (Greek Λ), associated with dark energy, and cold dark matter (abbreviated CDM). It is frequently referred to as the standard model of Big Bang cosmology, because it is the simplest model that provides a reasonably good account of the following properties of the cosmos: existence and structure of the cosmic microwave background; the large-scale structure in the distribution of galaxies; abundances of hydrogen (including deuterium), helium, and lithium; and the accelerating expansion of the universe observed in the light from distant galaxies and supernovae.

Plaxco, Kevin and Michael Gross. Astrobiology. Baltimore: Johns Hopkins University Press, 2006. A thorough text on the occasion of life and intelligence, broadly conceived, in a dynamically evolving cosmos.

Pudritz, Ralph, et al, eds. Planetary Systems and the Origins of Life. Cambridge: Cambridge University Press, 2007. New from the Cambridge Astrobiology series, the volume first updates protolife studies, and goes on to explore how suitable the planets and moons of our solar system might be for its viable presence.

Part I. Planetary Systems and the Origins of Life: 1. Observations of extrasolar planetary systems Shay Zucker; 2. The atmospheres of extrasolar planets L. Jeremy Richardson and Sara Seager; 3. Terrestrial planet formation Edward Thommes; 4. Protoplanetary disks, amino acids and the genetic code Paul Higgs and Ralph Pudritz; 5. Emergent phenomena in biology: the origin of cellular life David Deamer; Part II. Life on Earth: 6. Extremophiles: defining the envelope for the search for life in the Universe Lynn Rothschild; 7. Hyperthermophilic life on Earth - and on Mars? Karl Stetter; 8. Phylogenomics: how far back in the past can we go? Henner Brinkmann, Denis Baurain and Hervé Philippe; 9. Horizontal gene transfer, gene histories and the root of the tree of life Olga Zhaxybayeva and J. Peter Gogarten; 10. Evolutionary innovation versus ecological incumbency Adolf Seilacher; 11. Gradual origins for the Metazoans Alexandra Pontefract and Jonathan Stone; Part III. Life in the Solar System?: 12. The search for life on Mars Chris McKay; 13. Life in the dark dune spots of Mars: a testable hypothesis Eörs Szathmary, Tibor Ganti, Tamas Pocs, Andras Horvath, Akos Kereszturi, Szaniszlo Berzci and Andras Sik; 14. Titan: a new astrobiological vision from the Cassini-Huygens data François Raulin; 15. Europa, the Ocean Moon: tides, permeable ice, and life Richard Greenberg.

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