habitability Archives

Giant Planets Cast A Deadly Pall – How They Can Prevent Life In Other Solar Systems

by Keith CowingNovember 1, 2023November 1, 2023

Giant gas planets can be agents of chaos, ensuring nothing lives on their Earth-like neighbors around other stars. New studies show, in some planetary systems, the giants tend to kick […]

An artistic representation of how the northern infrared aurora would have looked like in 2006 (marked in red). The darker red locations indicate confirmed aurora locations, with fainter red used to mark possible aurora locations. Credit to NASA, ESA and M. Showalter (SETI Institute) for the background image of Uranus, as was observed by the Hubble Space Telescope (in the visible spectrum) in August 2005. Credit to NASA, ESA and M. Showalter (SETI Institute) for the background image of Uranus, as was observed by the Hubble Space Telescope (in the visible spectrum) in August 2005.

Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Press Release, Uranus

Uranus Aurora Discovery Offers Clues To Habitable Icy Worlds

by Keith CowingOctober 27, 2023October 27, 2023

The presence of an infrared aurora on the cold, outer planet of Uranus has been confirmed for the first time by University of Leicester astronomers.

Despite Venus being such a scorching wasteland, the planet is often referred to as Earth’s sister because of similarities in size, mass, density and volume. Photo: NASA/JPL

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Gaia - Planetary Perspectives, Habitable Zones, Press Release, Venus

Venus Had Earth-like Plate Tectonics Billions Of Tears Ago, Study Suggests

by Keith CowingOctober 27, 2023October 27, 2023

Venus, a scorching wasteland of a planet according to scientists, may have once had tectonic plate movements similar to those believed to have occurred on early Earth, a new study […]

Mass distribution of the stellar galaxy components (disc+bulge) at three different times (top to bottom: t ∈ {0, 5, 10} Gyr) for all simulations (left to right: LRM, LRM_UES, HRM) in face-on projection, i.e. in R – z plane. -- astro-ph.EP

AI - Data - Apps - Cybernetics, Astronomy & Telescopes, Habitable Zones, Status Report

Dynamical Aspects Of Galactic Habitability In N-body Simulations

by Keith CowingOctober 25, 2023October 25, 2023

Recent studies of Galactic evolution revealed that the dynamics of the stellar component might be one of the key factors when considering galactic habitability.

Illustration of our strategy to detect habitable exoplanetary environment via CO2 depletion. Each of the planets to the right hand side of the star describes a different scenario discussed in the text (along with illustrative atmospheric concentrations). The panel on the left hand side depicts a simulation of the transmission spectrum of the temperate terrestrial planet TRAPPIST-1 f. We explore the detectability of an atmosphere with ∼ 10 JWST/NIRSpec Prism transit observations, the minimum needed to produce a reliable diagnostic. Note that the deviation from a flat signal (no atmosphere) is primarily supported by the strong absorption features of CO2, notably at 4.3 µm (highlighted). Exo-atmospheric models from 142 were used to make that panel. On the lower right hand side, we illustrate a simplified view of a carbon cycle involving surface liquid water and biology sequestering cycle and producing a depletion in atmospheric carbon. Atmospheric concentrations given near the planets are illustrative. astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Status Report, TRAPPIST-1, Water/Hycean Worlds & Oceanography

Atmospheric Carbon Depletion As A Tracer Of Water Oceans And Biomass On Temperate Terrestrial Exoplanets

by Keith CowingOctober 24, 2023October 24, 2023

The conventional observables to identify a habitable or inhabited environment in exoplanets, such as an ocean glint or abundant atmospheric O2, will be challenging to detect with present or upcoming […]

Time evolution of the elemental abundances [X/Fe] for O, Mg, Si, and C against [Fe/H] for 푅 = 8 kpc in the models with different SNeII yields. Solid (green) lines represent our fiducial model with the ad hoc prescription; dashes (red) lines Nomoto et al. (2013) yields (N13); dash-dotted (blue) lines Nomoto et al. (2013) with hypernovae (fraction is 0.5) yields (N13+HN); dotted (magenta) line Chieffi & Limongi (2004) yields (CL04); dosh-dot-dotted (orange) lines Limongi & Chieffi (2018) yields (LC18). The observational data sources are the same as those used in Fig. 3. The large circles (red) represent the Sun’s values. -- astro-ph.GA

Astrochemistry, Astrogeology, Astronomy & Telescopes, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Status Report

Exploring The Sun’s Birth Radius And The Distribution Of Planet Building Blocks In The Milky Way Galaxy: A Multi-zone Galactic Chemical Evolution Approach

by Keith CowingOctober 21, 2023October 19, 2023

We explore the influence of the Milky Way galaxy’s chemical evolution on the formation, structure, and habitability of the Solar system. Using a multi-zone Galactic Chemical Evolution (GCE) model, we […]

The positions of the fragments in the (𝑎 − 𝑒) plane that collided with the Sun or one of the rocky planets for different impact velocities and angles (see Table 2). The upper panels depict simulations with 𝜃 = 30◦ while the lower panels for 𝜃 = 45◦ . The colors indicate the fragments colliding with the different celestial bodies, while the initial position of all bodies involved in the 𝑁-body simulation is indicated in grey in the background. -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Gaia - Planetary Perspectives, Habitable Zones, Icy Worlds, Meteorites & Asteroids, Origin & Evolution of Life, Status Report, Water/Hycean Worlds & Oceanography

The Evolution Of Collision Debris Near The ν6 Secular Resonance And Its Role In The Origin Of Terrestrial Water

by Keith CowingOctober 19, 2023October 19, 2023

This work presents novel findings that broadens our understanding of the amount of water that can be transported to Earth. The key innovation lies in the combined usage of Smoothed […]

Atmospheres, Climate, Weather, Gaia - Planetary Perspectives, Habitable Zones, Microbiology & Virology, Status Report

Detecting Microbiology In The Upper Atmosphere: Relative-velocity Filtered Sampling

by Keith CowingOctober 15, 2023October 15, 2023

The purpose of this paper is to re-open from a practical perspective the question of the extent in altitude of the Earth’s biosphere.

Extremeophiles and Extreme Environments, Habitable Zones, Origin & Evolution of Life, Status Report, Venus

Venus’ Atmospheric Chemistry and Cloud Characteristics Are Compatible with Venusian Life

by Keith CowingOctober 15, 2023October 15, 2023

Venus is Earth’s sister planet, with similar mass and density but an uninhabitably hot surface, an atmosphere with a water activity 50-100 times lower than anywhere on Earths’ surface, and […]

Bayesian analysis of the posterior likelihood of life, P(life|observation), based on assuming an observed value for network metrics and methane gas abundance. Given that the probability for life to exist on an exoplanet is unknown, we assess the posterior likelihood over a range of prior probabilities for life, P(life). Grey Regions highlight metric values that are associated with a zero probability of life and are therefore anti-biosignatures for the sets of models compared herein. In general, network metrics can provide greater constraints on the probability of life given a set of observations than CH4 abundance alone, allowing distinguishing cases where Earth-like methanogenesis can be ruled out even when CH4 abundance alone is not conclusive. -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Habitable Zones, Imaging & Spectroscopy, SETI & Technosignatures, Status Report

A Complex Systems Approach to Exoplanet Atmospheric Chemistry: New Prospects for Ruling Out the Possibility of Alien Life-As-We-Know-It

by Keith CowingOctober 10, 2023October 10, 2023

The near-term capability to characterize terrestrial exoplanet atmospheres may bring us closer to discovering alien life through atmospheric data.

habitability

Giant Planets Cast A Deadly Pall – How They Can Prevent Life In Other Solar Systems

Uranus Aurora Discovery Offers Clues To Habitable Icy Worlds

Venus Had Earth-like Plate Tectonics Billions Of Tears Ago, Study Suggests

Dynamical Aspects Of Galactic Habitability In N-body Simulations

Atmospheric Carbon Depletion As A Tracer Of Water Oceans And Biomass On Temperate Terrestrial Exoplanets

Exploring The Sun’s Birth Radius And The Distribution Of Planet Building Blocks In The Milky Way Galaxy: A Multi-zone Galactic Chemical Evolution Approach

The Evolution Of Collision Debris Near The ν6 Secular Resonance And Its Role In The Origin Of Terrestrial Water

Detecting Microbiology In The Upper Atmosphere: Relative-velocity Filtered Sampling

Venus’ Atmospheric Chemistry and Cloud Characteristics Are Compatible with Venusian Life

A Complex Systems Approach to Exoplanet Atmospheric Chemistry: New Prospects for Ruling Out the Possibility of Alien Life-As-We-Know-It

Early-career Graduate Students Host An Exclusive, NASA-funded Astrobiology Conference

Intimate Link Between Prebiotic Chemistry And Meteorites: Mechanisms Of Organic Molecule Formation

Microbial Mats Influence The Isotopic Composition And Provenance of Soil Organic Matter In The McMurdo Dry Valleys, Antarctica

Beyond The Prebiotic Soup: Solid Organic Films And Protocell-Like Formation in Prebiotic Discharge Experiments

From Searching For Extraterrestrial Biosignatures To Exploring The Origins Of Life: A Prebiotic Chemistry Perspective