III. Ecosmos: A Revolutionary Fertile, Habitable, Solar-Bioplanet, Incubator Lifescape
I. Our EarthMost Distinction: A Rarest Planetary Confluence of Life in Person Favorable Conditions
Gribbin, John. Alone in the Universe: Why Our Planet is Unique. Hoboken, NJ: Wiley, 2011. The British science writer is amazed that with a prolific chancery of swirling galaxies, stellar chaos, askew orbits, hot Jupiters, metallicities, wandering continental plates, cometary impacts, a funny sun, toxic atmospheres, along with life’s episodic, contingent evolution, rife with extinctions, and more, it’s a wonder we inquisitive earthlings are here at all. So, once more, by this train, it is concluded We are It, and ought to decisively avail our cosmic lottery winnings to save the world and green the galaxy.
And that chain (of coincidences) has so many weak links that it may mean that, for all the proliferation of stars and planets in the Universe, as an intelligent species we may be unique. (xiii) Whether or not you see the hand of God in any of this, it would mean that we are the most technologically advanced civilization in the Universe, and the only witnesses with an understanding of the origin and nature of the Universe itself. If humankind and Gaia can survive the present crises, the whole of the Milky way may become our home. If not, the death of Gaia may be an event of literally universal significance. (xv)
Hall, Shannon. Summer Solstice Mystery: Does the Earth’s Tilt Hold the Secret to Life? New York Times. June 21, 2018. With this timely article, one more special feature of our conducive bioplanet comes to scientific and public notice. Earth’s axial tilt or obliquity of 23.5 degree which gifts seasonal variations is well within a 10 to 40 degree range seen as necessary. Life’s biochemistry and developmental evolution to literate intelligence requires a steady, benign climate that does not lock into hot, gaseous or cold, frozen states. Bioastronomers Rene Heller, Rory Barnes, David Ferreira and others comment, along with citations such as Climate at High-Obliquity in Icarus (243/236, 2014) and Exo-Milankovitch Cycles II: Climates of G-dwarf Planets at arXiv:1805.00283. For more see Statistical Trends in the Obliquity Distribution of Exoplanet Systems at arXiv:1805.03654. Many exoworlds, and also their sunny stars, wobble but at lower or higher deleterious angles, which often change over time.
Milankovitch cycles describe the collective effects of changes in the Earth's movements on its climate over thousands of years. The term is named for Serbian geophysicist and astronomer Milutin Milanković. In the 1920s, he hypothesized that variations in eccentricity, axial tilt, and precession of the Earth's orbit resulted in cyclical variation in the solar radiation reaching the Earth, and that this orbital forcing strongly influenced climatic patterns on Earth. (Wikipedia)
Hall, Shannon. The Recipe for Other Earths. Nature. 552/20, 2017. A science writer reports upon efforts by geologists to understand our world make up so as to better evaluate whether exoplanet conditions might aid or inhibit a relative habitability.
But Earth has a lot more going for it than its size, mass and favourable orbit, says Cayman Unterborn (search), an exogeologist at Arizona State University in Tempe. Its churning molten core, for example, creates and sustains a magnetic field that shields the planet’s fragile atmosphere from the solar wind. And the motion of tectonic plates helps regulate global temperatures, by cycling carbon dioxide between rocks and the atmosphere. (21)
Hanlon, Michael. Save the Universe. Aeon Magazine. April, 2015. On this popular online salon, a British science journalist opens with a subtitle sentence: It is only a matter of time before our Universe goes black, cold and dies. Must this be the end of the road for life? Based on the latest scientific findings, since our precious Earthkind could well be the only phenomenal people and planet ever able to contravene and co-create, a future Save the Universe Project is proposed. The posting goes on to entertain mundane issues such as intentionally slowing down cosmic expansion within its aim to broach the very idea, possibility, vista, and challenge.
The Universe will end, not with a bang, but with a whimper, maybe 10 googol years from now. That is, if no one tries to do anything about it. So, what can be done? Should life surrender to its sad, entropic fate, or should we (for ‘we’ are the only entities we know of who might be able to make a difference) at least begin to think about postponing – perhaps indefinitely – the death of the only home we have? (3) The project is not really about saving the Universe, but about saving the life within it, life without which, after all, the cosmos is just gas and rocks and vacuum. It might prove that the ultimate answer to the problem of life, the universe and everything is not, as Douglas Adams joked, 42, but simply finding a way to keep the show on the road forever. (5)
Haqq-Misra, Jacob. Does the Evolution of Complex Life Depend on the Stellar Spectral Energy Distribution?. arXiv:1905.07343. The Blue Marble Space Institute, Seattle astrobiologist (search) adds another measured condition which is vital for biospheric life to develop into complex organisms. As the Abstract notes, the right intensity of solar radiation is needed over a sufficiently long span (a billion years for Earth), so that a global species as our own can appear.
This paper presents the proportional evolutionary time hypothesis, which posits that the mean time required for the evolution of complex life is a function of stellar mass. The "biological available window" is defined as the region of a stellar spectrum between 200 to 1200 nm that generates free energy for life. Over the ∼4 Gyr history of Earth, the total energy incident at the top of the atmosphere and within the biological available window is ∼1034 Joules. The hypothesis assumes that the rate of evolution from the origin of life to complex life is proportional to this total energy, which would suggest that planets orbiting other stars should not show signs of complex life if the total energy incident on the planet is below this energy threshold. (Abstract)
Haqq-Misra, Jacob, et al. Observational Constraints on the Great Filter. arXiv:2002.08776. We cite this entry by Blue Marble Space Institute, and NASA Goddard astroscientists becauses it identifies a bottleneck or check point that a planetary to cosmic civilization must successfully pass through. The abstract and quote discuss its various straits and where the certification barrier might be. It is then alluded that for an apocalyptic Earth-like bioworld, the critical condition may be whether the emergent transition to a unified personsphere progeny can be accomplished. In specific regard, our 2020 introduction is considers the presence of some kind of second singularity event.
The search for spectroscopic biosignatures with the next-generation of space telescopes could provide observational constraints on the abundance of exoplanets with signs of life. Current mission concepts that would observe ultraviolet to near-infrared wavelengths could place upper limits on the fraction of planets in the galaxy that host life. We note that searching for technosignatures alongside biosignatures would provide important knowledge about the future of our civilization. If technical civilizations are found, then we can increase our confidence that the hardest step in planetary evolution--the Great Filter--is probably in our past. But if we find life to be common but nothing else, then this would increase the likelihood that the Great Filter awaits to challenge us in the future. (Abstract excerpt)
Hatzes, Artie. The Architecture of Exoplanets. Space Science Reviews. 205/1-4, 2016. A Friedrich Schiller University, Jena astronomer divides this Earthwise study of a prolific cosmos known since 1995 to fill itself with orbital worlds into two phases. Before the 2009 Kepler satellite launch, our own home orrery was still used as the standard model. In the years since, all possible manner of celestial objects from planetesimals to small rocky orbs, super Earths, gas giants, and solar systems will a large range of stellar modes, often as binary pairs. But a analog of the familiar museum icon of nine planets in an orderly, circular series has not been found. Search Konstantin Batygin, et al for scientific reports, and The Way Forward at arXiv:1603.08238 about how studies might proceed as this auspicious finding sinks in.
Prior to the discovery of exoplanets our expectations of their architecture were largely driven by the properties of our solar system. We expected giant planets to lie in the outer regions and rocky planets in the inner regions. Planetary orbits should be circular, prograde and in the same plane. The reality of exoplanets have shattered these expectations. Jupiter-mass, Neptune-mass, Superearths, and even Earth-mass planets can orbit within 0.05 AU of the stars, sometimes with orbital periods of less than one day. Exoplanetary orbits can be eccentric, misaligned, and even in retrograde orbits. This was put on a firm statistical basis with the Kepler mission that clearly demonstrated that there were more Neptune- and Superearth-sized planets than Jupiter-sized planets. These are often in multiple, densely packed systems where the planets all orbit within 0.3 AU of the star, a result also suggested by radial velocity surveys. Exoplanets also exhibit diversity along the main sequence. Giant planets around low mass stars are rare, but these stars show an abundance of small (Neptune and Superearth) planets in multiple systems. We have yet to find a planetary system that is analogous to our own solar system. The question of how unique are the properties of our own solar system remains unanswered. Advancements in the detection methods of small planets over a wide range of orbital distances is needed before we gain a complete understanding of the architecture of exoplanetary systems. (Abstract)
Hoang, John, et al. Exploring the Use of Generative AI in the Search for Extraterrestrial Intelligence (SETI). arXiv:2308.13125. In the context of the Breakthrough Listen project, Yale, Ohio State, Toronto, and UC Berkeley computer scientists propose to integrate and advance prior surveillance methods with deep language learning with capabilities.
The search for extraterrestrial intelligence (SETI) is a field that has long been within the domain of traditional signal processing techniques. However, with the advent of powerful generative AI models, such as GPT-3, we are now able to explore new ways of analyzing SETI data and potentially uncover previously hidden signals. In this work, we present a novel approach for using generative AI to analyze SETI data, with focus on data processing and machine learning techniques. Our proposed method uses a combination of deep learning and generative models to analyze radio telescope data, with the goal of identifying potential signals from extraterrestrial civilizations.
Holmes, Bob. The Goldilocks Planet. New Scientist. March 23, 2019. A science writer makes a case that the presence of a Gaian self-maintaining biosphere should be seen as another major reason why this Earth is uniquely viable in the cosmos. Three properties are here cited that help this to happen – redundancy, diversity, and modularity – along with niche construction, group selection, and more.
As far as we know, Earth is a one-off: there is no population of competing, reproducing planets for natural selection to choose between to form the next generation. And yet, like a superorganism honed by evolution, Earth seems to self-regulate in ways that are essential for life. Oxygen levels have remained relatively constant for hundreds of millions of years, as has the availability of key building blocks of life such as carbon, nitrogen and phosphorus. Crucially, Earth’s surface temperature has remained with the narrow range that allows liquid water to exist. (35)
Hong, Yu-Cian, et al. Innocent Bystanders: Orbital Dynamics of Exomoons during Planet-Planet Scattering. arXiv:1712.06500. We note this entry by Hong, Philip Nicholson, and Jonathan Lunine, Cornell University, and Sean Raymond, University of Bordeaux because, as the Abstract cites, it gives a sense of how involved, chancy and chaotic the formation of long duration, evolutionary bioworlds seems to be. This may be why, we muse, on a statistical basis the universe needs a quintillion candidates so that at least one fittest Earth-like planet might be able to self-discover, realize and select.
Horner, Jonathan, et al. The Influence of Jupiter, Mars and Venus on Earth’s Orbital Evolution. arXiv:1708.03448. Australian and British astroscientists including David Waltham consider still another closely finessed attribute of this solar system which is necessary for an extended benign period of Earth life evolution.
n the coming years, it is likely that the first potentially Earth-like planets will be discovered orbiting other stars. Once found, the characterisation of those planets will play a vital role in determining which will be chosen as the first targets for the search for life beyond the Solar System. One of the plethora of factors to be considered in that process is the climatic variability of the exo-Earths in question. In the Solar System, the Earth's long-term climate is driven by several factors, including the modifying influence of life on our atmosphere, and the temporal evolution of solar luminosity. The gravitational influence of the other planets in the Solar System adds an extra complication, driving the Milankovitch cycles (2nd quote) that are thought to have caused the on-going series of glacial and interglacial periods that have dominated Earth's climate for the past few million years. Our results illustrate how small changes to the architecture of a given planetary system can result in marked changes in the potential habitability of the planets therein, and are an important first step in developing a means by which the nature of climate variability on planets beyond our Solar System can be characterised. (Abstract)
Jiang, Jonathan, et al.
Avoiding the Great Filter: Predicting the Timeline for Humanity to Reach Kardashev Type I Civilization.
Seven scholars from the USA and China exercise a study of how and when our whole planetary abide might sufficiently be able to sustain itself. But on June 1, 2022 national sovereignties seem obsessed with nuclear war. Maybe the final test is not about such material aspects but need involve some Earthwise awake, aware cognitive choice to stop fighting, peaceably unify and begin a common quest(ion).
The level of technological development of any civilization can be gauged in large part by the amount of energy produced for its usage, along with their global stewardship of its home world. Following the (Nikolai) Kardashev definition, a Type I civilization is able to store and use all the energy available on its planet. In this study, we analyze three important energy sources: fossil fuels, nuclear, and renewable. We also consider environmental limitations specific to our calculations, to predict when humanity will reach the level of a Kardashev Scale Type I civilization. (excerpt)