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

I. Our EarthMost Occasion: A Rarest Confluence of Favorable Features and Close Calls

Koksal, Elif, et al. Spontaneous Formation of Prebiotic Compartment Colonies on Hadean Earth and Pre-Noachian Mars. ChemSystemsChem. 4/3, 2022. This new Chemistry Europe publication is dedicated to the Systems Chemistry endeavor, which has not been recently had its own journal. Here a six person team from the University of Oslo, Vienna and Copenhagen because it reports how early planetary crustal environs possess intrinsic conditions which favor the formation of autonomous protocellular aggregates. These bounded capsules can then facilitate non-enymatic DNA reactions. As such studies advance into the 2020s they reveal further evidence of an innate ecosmic fertility.

Kopparapu,, Ravi, et al. Characterizing Exoplanet Habitability. Meadows, Victoria, et al, eds. Planetary Astrobiology. Tempe: University of Arizona Press, 2020. As stellar, galactic, and universal frontiers open to satellite, atmospheric, spectroscopy, geologic, computational and other surveys, RK, Goddard Space Center, Eric Wolf, University of Colorado, and Victoria Meadows, University of Washington discuss how to proceed with a cosmic neighbor census. But as explorations go forth they are finding vicarious contingencies which winnow habitations by way of a long series of conducive conditions that must be met. A large Factors Affecting Habitability graphic depicts some 50 issues such as sun type, spectral energy, solar orbits, metallicity, UV rays, watery basins, a mediating moon and so on. As this section records, it ought to soon dawn upon us that a population of only one fittest Earthropic optimum may exist. See also How to Characterize Habitable Worlds and Signs of Life by Lisa Kaltenegger in the Annual Review of Astronomy and Astrophysics (55/433, 2017).

Habitability is a measure of an environment's potential to support life, which means liquid water on its surface. This condition depends on a complex set of interactions between planetary, stellar, planetary system and even galactic features and processes. We describe the latest way to test which exoplanets are likely to be terrestrial, and how to define the habitable zone under different assumptions. We are now entering an exciting era of exoplanet atmospheric studies, with more powerful observing capabilities planned for the near and far future. Understanding the processes that affect the habitability of a planet will guide us in discovering habitable, and potentially inhabited, planets. (Abstract excerpt)

Kouvenhoven, M. B. N, et al. Planetary Systems in Star Clusters. arXiv:1609.00898. After two decades of scientific realizations of a radically different cosmos that fills itself with planetary objects of all manner of types, sizes and stellar locales, a team of astrophysicists with joint Chinese and Dutch postings add another observation of how our own sun system is uniquely special. Most stars, as also galaxies, actually tend to collect and bunch together, so that planets in these jumbled environs are not in circular orbits but “scatter and disperse” widely.

Thousands of confirmed and candidate exoplanets have been identified in recent years. Consequently, theoretical research on the formation and dynamical evolution of planetary systems has seen a boost, and the processes of planet-planet scattering, secular evolution, and interaction between planets and gas/debris disks have been well-studied. Almost all of this work has focused on the formation and evolution of isolated planetary systems, and neglect the effect of external influences, such as the gravitational interaction with neighbouring stars. Most stars, however, form in clustered environments that either quickly disperse, or evolve into open clusters. Under these conditions, young planetary systems experience frequent close encounters with other stars, at least during the first 1-10 Myr, which affects planets orbiting at any period range, as well as their debris structures. (Abstract)

Krakauer, David and Caitlin McShea, eds. InterPlanetary Transmissions: Proceedings of the Santa Fe Institute’s First InterPlanetary Festiva. Santa Fe: SFI Press, 2019. The chapters such as Intelligent Systems, Autonomous Ecosystems, Origins of Life in Space, and Living in Space are transcripts of group discussions with luminaries such as Jessica Flack, Geoffrey West, Caleb Scharf, Jennifer Dunne, Neal Stepheson, and many more diverse voices.

This volume is a record of the proceedings of the first InterPlanetary Festival, held in Santa Fe, New Mexico, in June of 2018 by the Santa Fe Institute. An annual free public event, the InterPlanetary Festival combines an exploration of complexity science, which SFI has pioneered, and technological innovation with a summer festival full of music, film, art, food, drinks, and more. The first project of its kind to combine celebration with experimentation, and conversation with analysis, the InterPlanetary Project seeks to be nothing less than a whole-planet project—beyond borders, beyond politics, beyond economics—to activate the collective intelligence of our first planet: Earth.

Lammer, Helmet, et al. The Role of Nitrogen as a GeoBiosignature for the Detection and Characterization of Earth-like Habitats. arXiv:1904.11716. A seven member group mainly from the Austrian Academy of Sciences Space Research Institute cites that the appropriate presence of this globally atmospheric and chemical element ought to be seen as another important factor for life’s emergent evolution.

Since the Archean, nitrogen has been a major atmospheric constituent in Earth's atmosphere. It is an essential element in the building blocks of life, therefore the geobiological nitrogen cycle is a fundamental factor in the long term evolution of both Earth and Earth-like exoplanets. We discuss the development of the Earth's N2 atmosphere since the planet's formation and its relation with the geobiological cycle. Then we suggest atmospheric evolution scenarios and their possible interaction with life forms for a stagnant-lid anoxic world, a tectonically active anoxic world, and an oxidized tectonically active world. Since life forms are the most efficient means for recycling deposited nitrogen back into the atmosphere nowadays, they sustain its surface partial pressure at high levels. (Abstract excerpt)

Lineweaver, Charles and Molly Townes O’Brien. The Cosmic Context of the Millennium Development Goals: Maximum Entropy and Sustainability. Thomas Faunce, ed. Nanotechnology Toward the Sustainocene. Singapore: Pan Stanford Publishing, 2015. An Australian National University astronomer and law professor expansively situate our crucial imperative to achieve a better populace and planet within a widest temporal and spatial evolutionary locus. In this whole scenario, a global transition to organic viability would contribute to the arrow and advance of informed, personified order over disorderly dissipations.

Life forms are a subset of the organized structures in the universe known as far-from equilibrium dissipative systems (FarFEDS). FarFEDS are dissipative structures that, while maintaining their structure, convert low-entropy energy to high-entropy energy. They include galaxies, stars, convection cells, typhoons, fires, humans, and bacteria. All FarFEDS (and thus all life forms) extract free energy from the environment and turn it into waste heat faster than random processes such as diffusion would be able to do. (41-42)

Lingam, Manasvi. Implications of Abiotic Oxygen Buildup for Earth-like Complex Life. arXiv:2002.03248. A Florida Institute of Technology astrophysicist (search) surveys the importance for a bioworld to achieve a favorable atmospheric O2 level in the low 20% range for life to be able to develop and evolve. This small window between starved and burnt up need be reached in a timely way (Lineweaver) and persist over relatively long periods. This atmospheric quality would then be a vital biosignature. See also Ward, Lewis, et al. Follow the Oxygen: Comparative Histories of Planetary Oxygenation and Opportunities for Aerobic Life by Lewis Ward, et al in Astrobiology (19/6, 2019). In regard, still another vital, finely tuned check point to successfully pass through is highlighted.

One of the chief paradoxes of molecular oxygen (O2) is that it is an essential requirement for multicellular eukaryotes on Earth while simultaneously posing a threat to their survival via the formation of reactive oxygen species. In this paper, the constraints imposed by O2 on Earth-like complex life are applied to whether worlds with abiotic O2 inventories can harbor such organisms. By consideration of the O2 sources and sinks of Earth-like planets, it is proposed that worlds with X-ray and extreme ultraviolet fluxes might not host complex lifeforms because the photolysis of water molecules may cause high O2 buildup. (Abstract excerpt)

Lingam, Manasvi and Abraham Loeb. Dependence of Biological Activity on the Surface Water Fraction of Planets. arXiv:1809.09118. The Harvard University, Institute for Theory and Computation postdoc and director team (search) continue their studies of extraterrestrial life by noting a critically vital feature of this habitable Earth, namely a 30% land and 70% ocean ratio maintained over some three billion years. As such multiphase exoplanet research proceeds apace, it is becoming evident that this dual division is a rarest state. The common spherical default is wholly dry, watery or gaseous. Plate tectonic movements are then seen to add a significant favorable condition (still going on in the Pacific rim of fire). A previous entry (L & L, 1804.02271) considered the effect of stellar physics on planetary life. As this section seeks to report, our home sapient Earth seems to be an increasingly special bioplanet amongst myriad vicarious candidates. This is an awesome, unexpected finding in need of much public report and notice, at a same time when nuclear nations are in headlong regression.

One of the unique features associated with the Earth is that the fraction of its surface covered by land is comparable to that spanned by its oceans and other water bodies. Here, we investigate how extraterrestrial biospheres depend on the ratio of the surficial land and water fractions. We find that worlds that are overwhelmingly dominated by landmasses or oceans are likely to have sparse biospheres. Our analysis suggests that major evolutionary events such as the buildup of O2 in the atmosphere and the emergence of technological intelligence might be relatively feasible only on a small subset of worlds with surface water fractions ranging approximately between 30% and 90%. We also discuss how our predictions can be evaluated by future observations, and the implications for the prevalence of microbial and technological species in the Universe. (Abstract)

The paper is organized as follows. In Sec. 2, we examine the biological potential of extraterrestrial biospheres and discuss the consequences for the buildup of O2 in the atmosphere. In Sec. 3, we discuss how the emergence of technological intelligence may depend on the surficial land-water ratio of these worlds. We follow this up with a discussion of how common are worlds with surface landmasses and oceans in Sec. 4. (2)

The emergence of technological intelligence turned out to be very sensitive to the size of the world, i.e. larger worlds are endowed with a significant advantage. For Earth-sized worlds, a water fraction of 30-90% might ensure that the likelihood of technological intelligence relative to the Earth is reasonably high. We also found that the Earth’s value of δw (ratio of land to water) appears to be close to the optimum with respect to the emergence of technological species. (10)

Lingam, Manasvi and Abraham Loeb. Implications of Tides for Life on Exoplanets. arXiv:1707.04594. Harvard-Smithsonian Center for Astrophysics theorists consider this geospheric surface condition which could have a major influence on long-term habitability. Our own Earth-moon system is an optimum situation of moderate tidal flows and basins, whereof cellular life can begin its evolutionary course. However, on the many other exoworlds just being found, this stable state maybe a rare occurrence. A corollary or default phase has become known “tidal locking” whence an orbiting object enters a tandem rotation with a host star or moon, see Tidal Locking of Habitable Exoplanets by Rory Barnes herein.

As evident from the nearby examples of Proxima Centauri and TRAPPIST-1, Earth-sized planets in the habitable zone of low-mass stars are common. Here, we focus on such planetary systems and argue that their (oceanic) tides could be more prominent due to stronger tidal forces. We identify the conditions under which tides may exert a significant positive influence on biotic processes including abiogenesis, biological rhythms, nutrient upwelling and stimulating photosynthesis. We conclude our analysis with the identification of large-scale algal blooms as potential temporal biosignatures in reflectance light curves that can arise indirectly as a consequence of strong tidal forces. (Abstract)

Lingam, Manasvi and Abraham Loeb. Physical Constraints for the Evolution of Life on Exoplanets. arXiv:1810:02007. Some two weeks after a posting (1809.09118, see also 1807.08879, 1804.02271) about how plate tectonics can effect habitability, this Harvard team, funded in part by the Breakthrough Foundation, here view additional vicarious cosmic, solar, and geologic influences such as stellar coronal winds and flares, planetary magnetospheres, oceanic and atmospheric evaporations, electromagnetic radiation, relative oxygen buildup, origins of life, photosynthesis, and more in mathematic detail. These studies are then supported with some 300 references. Once again, this home Earth whereupon a sapient species is altogether able to explore, quantify and learn, seems to be an increasingly unique candidate personsphere.

Some two weeks after a posting (1809.09118, see also 1807.08879, 1804.02271) about how plate tectonics can effect habitability, this Harvard team, funded in part by the Breakthrough Foundation, here view additional vicarious cosmic, solar, and geologic influences such as stellar coronal winds and flares, planetary magnetospheres, oceanic and atmospheric evaporations, electromagnetic radiation, relative oxygen buildup, origins of life, photosynthesis, and more in mathematic detail. These studies are then supported with some 300 references. Once again, this home Earth whereupon a sapient species is altogether able to explore, quantify and learn, seems to be an increasingly unique candidate personsphere.

Lingam, Manasvi and Abraham Loeb. Role of Stellar Physics in Regulating the Critical Steps for Life. arXiv:1804.02271. Harvard University, Institute for Theory and Computation (see below), astrophysicists (postdoc and director) enter a 34 page, 200 reference paper as much about how the major evolutionary transitions scale (see Szathmary, Section VI. H. 8) is a good guide to the active quest for exoplanetary life and mind. Here five main stages of Prokaryotes, Eukaryotes, Plastids (organelles), Complex Multicellularity, and Human Persons (homo sapiens) are proposed, with Oxygenic photosynthesis, land invasion, and technological intelligence as subsets. By this view, an “extended habitability” zone is drawn for Earth of a prior 4.5 billion past years (Gyr), and 1-2 Gyr ahead.

With this sketch in place, the effects of solar type (our sun is a G yellow dwarf), variable radiative intensities, and other stellar aspects, are considered with regard to original, primitive biochemical, unicell phases and their evolution all the way to technical civilizations. It is then noted that while teleological progress is out of favor, this well researched, episodic course from primal microbes to literate peoples does trace an oriented ascent. And if to wonder about it all in 2018, a worldwide humankinder seems well on her/his way to an organic, procreative ecosmos, stochastic to be sure, which fills itself with potentially habitable bioworlds and embryogeneses toward salutary self-discovery.

We us the critical step model to study the major transitions in evolution on Earth. We find that a total of five steps represents the most plausible estimate, in agreement with previous studies, and use the fossil record to identify the potential candidates. We apply the model to Earth-analogs around stars of different masses by incorporating the constraints on habitability set by stellar physics including the habitable zone lifetime, availability of ultraviolet radiation for prebiotic chemistry, and atmospheric escape. The critical step model suggests that the habitability of Earth-analogs around M-dwarfs is significantly suppressed. The total number of stars with planets containing detectable biosignatures of microbial life is expected to be highest for K-dwarfs. In contrast, we find that the corresponding value for intelligent life (technosignatures) should be highest for solar-mass stars. Thus, our work may assist in the identification of suitable targets in the search for biosignatures and technosignatures. (Abstract)

Harvard University Institute for Theory and Computation The mission of the ITC is to advance our knowledge and understanding of the universe through computational and analytical means, to create a forum for exploration and discoveries in theoretical astrophysics, and to train the next generation of astrophysicists. ITC addresses a wide variety of problems such as simulations of galaxy formation in the Universe, large scale structure in the universe, accretion of gas onto black holes, the first stars & black holes and the search for life and planet formation.

Livingston, John. One Cosmic Instant. Boston: Houghton Mifflin, 1973. Some 35 years ago the York University environmentalist placed earth’s increasing ecological stress, evident even then, in the long perspective of a special bioplanet whose life evolves to human technological sentience, only to place itself at terminal peril. Today it is often said that we have already overshot a global carrying capacity, that earth has a fever, temperature unknown, that its physiology can in fact perish. By this view, we have indeed reached a second singularity which requires our mindful self-selection.

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