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

G. An Astrochemistry to Astrobiological Spontaneity

Meinert, Cornelia, et al. Ribose and Related Sugars from Ultraviolet Irradiation of Interstellar Ice Analogs. Science. 352/208, 2016. An eight person team with postings in France, Mexico, and Denmark found that complex prebiotic molecules can be formed in a celestial medium of water, methanol, and ammonia under UV radiation. The most significant is the R in RNA, as a news report notes, which is a key precursor for life and limb.

Ribose is the central molecular subunit in RNA, but the prebiotic origin of ribose remains unknown. We observed the formation of substantial quantities of ribose and a diversity of structurally related sugar molecules such as arabinose, xylose, and lyxose in the room-temperature organic residues of photo-processed interstellar ice analogs initially composed of H2O, CH3OH, and NH3. Our results suggest that the generation of numerous sugar molecules, including the aldopentose ribose, may be possible from photochemical and thermal treatment of cosmic ices in the late stages of the solar nebula. Our detection of ribose provides plausible insights into the chemical processes that could lead to formation of biologically relevant molecules in suitable planetary environments. (Abstract)

Meyer, Michael. Recipes for Planet Formation. Physics World. November-December, 2009. The director of the Star and Planet Formation Research Group at the Institute for Astronomy, ETH, Zurich, surveys the latest science as humankind reconstructs how our ovular earth came to be, and begins to realize a fertile cosmos which by its innate nature forms planetary objects wherever and however possible.

Millar, T. J.. Faraday Discussion on Astrochemistry at High Resolution. arXiv.2307.13350. An emeritus Queen’s University Belfast astroscholar provides concluding remarks as a fifty year retrospect of scientific discoveries across the galactic raiment of the natural occasion of an increasing presence of just biochemical precursors that innate living complexities require to reach an evolutionary development. The survey courses from early 1970 assays to today’s computational prowess.

Fifty years on from the first detailed chemical kinetic modelling of astronomical sources, I provide some introductory comments on the history of astrochemistry, summarise some personal views on the topics covered in this discussion meeting, and conclude with some thoughts on its future development.

The development of astrochemistry over the past 50 years has been astounding, driven forward by the innovation of thousands of scientists, engineers and technicians whose ingenuity has led to the availability of facilities such as the ALMA and JWST. With these, we are able to probe astrochemistry from galactic size scales at high redshi, to au scales in protoplanetary disks and to even smaller scales in exoplanetary atmospheres. (9)

NASA, Astrobiological Institute. Abstracts. Astrobiology. 5/2, 2005. From the biennial meeting of the NAI, April 2005, summaries of many papers in these areas: Formation and Evolution of Planetary Systems, Extrasolar Planets, Origins of Life, Futures Technologies, Exploration and Societal Issues, Evolution of Life, Tracing Life, and Evolution in the Solar System. A survey of the latest projects and progress as earthkind seeks to comprehend the universe and itself.

Navrotsky, Alexandra and Kristina Lilova. Materials of the Universe: The Final Chemical Frontier. ACS Earth and Space Chemistry. 5/8, 2021. Arizona State University astrochemists introduce a virtual collection of topical papers from refractory ceramics to organic solids.

The concept of Materials of the Universe (MotU) is to unite cosmology, astrophysics, astronomy, planetary science, mineralogy, and petrology with materials science, chemistry, physics, and biology to address their complex evolutionary chemistries. We need to understand their formation, stability, catalytic activity, and rheology over a range of temperatures, pressures, and compositions not yet imagined. This MotU Special Issue has contributions across science, technology, engineering, and mathematics (STEM) fields inspired by materials under extreme conditions at low- and high-temperature and pressure, ultrahigh-vacuum, radiation fields, and far from equilibrium conditions.

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)

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