Gaia Archives

Paleopoles based on averages of sample Virtual Geomagnetic Poles (VGPs) rather than site VGPs.

Astrogeology, Biogeochemical Cycles & Geobiology, Gaia - Planetary Perspectives, Press Release

Study Shows Movement Of Tectonic Plates 3.5 Billion Years Ago

by Keith CowingMarch 24, 2026March 24, 2026

The history of the Earth is written on the great tablets of tectonic plates.

Strength of key long-term feedbacks governing Earth’s climate system (D. S. Abbot 2016; D. D. B. Koll & T. W. Cronin 2018; C. W. Arnscheidt & D. H. Rothman 2020; P. Forster et al. 2021). Each bar represents the feedback parameter in W m−2 K−1, estimated from Earth system model assessments and paleoclimate constraints. The upper axis shows the approximate feedback strength associated with a 50 K climate perturbation, representative of transitions between major states (e.g., snowball to temperate). Feedbacks are sorted by magnitude. Negative values (blue) represent stabilizing feedback that dampens temperature changes, while positive values (orange) indicate destabilizing feedback that amplifies them. Outgoing longwave radiation and the carbonate–silicate cycle are among the strongest stabilizing processes, while the ice–albedo feedback exerts a strong destabilizing influence. Models incorporating the three dominant types of feedback explain the general behavior of Earth’s long-term mean climate. -- The Planetary Science Journal

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Habitable Zones, Status Report

Not Earth-like Yet Temperate? More Generic Climate Feedback Configurations Still Allow Temperate Climates in Habitable Zone Exo-Earth Candidates

by Keith CowingMarch 20, 2026March 20, 2026

Earth’s climate is influenced by over a dozen types of feedback, but only three dominate its long-term climate behavior. Models of the exoplanet habitable zone (HZ) assume that this is […]

Allan Hills, Antarctica Credit: Photo by Austin Carter, COLDEX

Arctic / Antarctic / Alpine, Atmospheres, Climate, Weather, Gaia - Planetary Perspectives, Habitable Zones, Press Release

Course Correction Needed Quickly To Avoid Pathway To ‘Hothouse Earth’ Scenario

by Keith CowingFebruary 15, 2026February 15, 2026

Scientists say multiple Earth system components appear closer to destabilization than previously believed, putting the planet in increased danger of following a “hothouse” path driven by feedback loops that can […]

Strength of key long-term feedbacks governing Earth’s climate system (Forster et al. 2021; Arnscheidt & Rothman 2020; Abbot 2016; Koll & Cronin 2018). Each bar represents the feedback parameter in W m−2 K −1 , estimated from Earth system model assessments and paleoclimate constraints. The upper axis shows the approximate feedback strength associated with a 50 K climate perturbation, representative of transitions between major states (e.g., snowball to temperate). Feedbacks are sorted by magnitude. Negative values (blue) represent stabilizing feedbacks that damp temperature changes, while positive values (orange) indicate destabilizing feedbacks that amplify them. Outgoing longwave radiation and the carbonate–silicate cycle are among the strongest stabilizing processes, while the ice–albedo feedback exerts a strong destabilizing influence. Models incorporating the three dominant feedbacks explain the general behavior of Earth’s long-term mean climate. -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Habitable Zones, Status Report

Not Earth-like Yet Temperate? More Generic Climate Feedback Configurations Still Allow Temperate Climates in Habitable Zone Exo-Earth Candidates

by Keith CowingFebruary 14, 2026February 14, 2026

Earth’s climate is influenced by over a dozen feedbacks, but only three dominate its long-term climate behavior. Models of the exoplanet habitable zone (HZ) assume that this is similar for […]

A schematic of the key processes included in our abiotic Earth model. Remotely observable quantities (surface temperature, albedo, and atmospheric H2O and CO2) are in bold. Volatile cycling is diagrammed in more detail in Figure 2. -- astro-ph.EP

Analog Studies, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Habitable Zones, Origin & Evolution of Life, Status Report, Water/Hycean Worlds & Oceanography

A Whole-planet Model Of The Earth Without Life For Terrestrial Exoplanet Studies

by Keith CowingFebruary 3, 2026February 3, 2026

As the only known habitable (and inhabited) planet in the universe, Earth informs our search for life elsewhere. Future telescopes like the Habitable Worlds Observatory (HWO) will soon look for […]

A schematic illustration of the evolution of the Earth System

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Gaia - Planetary Perspectives, Habitable Zones, Status Report, Water/Hycean Worlds & Oceanography

Setting Up The Physical Principles Of Resilience In A Model Of The Earth System

by Keith CowingJanuary 18, 2026January 18, 2026

Resilience is a property of social, ecological, social-ecological and biophysical systems. It describes the capacity of a system to cope with, adapt to and innovate in response to a changing […]

A decision tree strategy for characterizing Earth-like exoplanets (Young et al. 2024). This tree indicates which gasses to observe, and in which order, to detect the biosignatures of Earth through time and rule out relevant false positives. The blue path was followed in spectral retrievals of Young et al. (2024) to categorize modern Earth, and the orange path for Archean Earth. Reproduced with permission from Young et al. (2024).-- astro-ph.IM

Astronomy & Telescopes, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Gaia - Planetary Perspectives, Habitable Zones, NASA Astrobiology Program, Status Report

Habitable Worlds Observatory (HWO): Living Worlds Community Working Group: The Search for Life on Potentially Habitable Exoplanets

by Keith CowingJanuary 16, 2026January 16, 2026

The discovery of a biosphere on another planet would transform how we view ourselves, and our planet Earth, in relation to the rest of the cosmos.

(A) Predicted pO2 (red line) and (B) pCO2 (purple line) values are compared for a range of possible assumed pN2. Vertical dashed lines and colored bands reflect pN2 estimates for 1.44 Ga. from existing models (22–26). For O2, the green and yellow bands reflect the thresholds for early animal respiration and full O3 shielding, respectively (31, 32). The pO2 safely exceeds these thresholds (0.01 PAL) if pN2 exceeded 0.2 bar. For CO2, horizontal dashed lines reflect estimated CO2 contents necessary to achieve the specified temperature (33–35). The diagonal line extrapolates from Archean atmospheric models that account for the effect of total atmospheric pressure on the required CO2 to keep the planet warm (35). Based on these points, our data suggests modern-like climates were possible if pN2 exceeded 0.5 bar. -- PNAS

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Gaia - Planetary Perspectives, Status Report

Direct Constraints From 1.4 Ga Fluid Inclusions Reveal A Fair Climate And Oxygenated Atmosphere

by Keith CowingJanuary 8, 2026January 8, 2026

The Mesoproterozoic eon, often regarded as mundane and static, lays the foundation for dramatic transformations in Earth’s physical and biological evolution during the subsequent Neoproterozoic.

Searching for life on other worlds can provide benefits to our home world -- Grok via Astrobiology.com

Astrobiology (general), Astropharmacy / Biotechnology, Atmospheres, Climate, Weather, Away Teams & Field Reports, Commercial & Private Sector, Gaia - Planetary Perspectives, Habitable Zones, Icy Worlds, Lava / magma ocean / Volcanic Worlds, Missions & Hardware, Nanotechnology & SynBio, NASA Astrobiology Program, Origin & Evolution of Life, Reports, Roadmaps, & Plans, Science Fiction, Status Report, Tricorders & Sensors, Water/Hycean Worlds & Oceanography

Searching For Extraterrestrial Life Advances Terrestrial Sustainability

by Keith CowingJanuary 5, 2026January 2, 2026

Astrobiology, while traditionally focused on understanding the origin of life on Earth and the potential for life elsewhere, offers powerful tools and insights for addressing urgent challenges on our planet.

The future lifespan of the terrestrial biosphere is only significantly shortened if seafloor weathering account

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Gaia - Planetary Perspectives, Habitable Zones, Status Report, Water/Hycean Worlds & Oceanography

Seafloor Weathering and Stochastic Outgassing Unlikely to Significantly Shorten the Future Lifespan of Earth’s Terrestrial Biosphere

by Keith CowingJanuary 5, 2026January 2, 2026

Current understanding suggests that as the Sun brightens in the far future, Earth’s carbonate-silicate cycle will offset increasing temperatures by drawing CO2 out of the atmosphere, ultimately leading to the […]

Gaia

Study Shows Movement Of Tectonic Plates 3.5 Billion Years Ago

Not Earth-like Yet Temperate? More Generic Climate Feedback Configurations Still Allow Temperate Climates in Habitable Zone Exo-Earth Candidates

Course Correction Needed Quickly To Avoid Pathway To ‘Hothouse Earth’ Scenario

Not Earth-like Yet Temperate? More Generic Climate Feedback Configurations Still Allow Temperate Climates in Habitable Zone Exo-Earth Candidates

A Whole-planet Model Of The Earth Without Life For Terrestrial Exoplanet Studies

Setting Up The Physical Principles Of Resilience In A Model Of The Earth System

Habitable Worlds Observatory (HWO): Living Worlds Community Working Group: The Search for Life on Potentially Habitable Exoplanets

Direct Constraints From 1.4 Ga Fluid Inclusions Reveal A Fair Climate And Oxygenated Atmosphere

Searching For Extraterrestrial Life Advances Terrestrial Sustainability

Seafloor Weathering and Stochastic Outgassing Unlikely to Significantly Shorten the Future Lifespan of Earth’s Terrestrial Biosphere

NASA Planetary Protection Handbook

NASA Scientists Search For Clues About Mars’ Past In Scotland

A Temperate Sub-Neptune Transiting The M4 Dwarf TOI-210 Identified By NIRPS And TESS — Uncovering Hidden M-dwarf Planetary Systems In The Near-infrared

Nonequilibrium Formation of Pyridine (C5H5N) in Interstellar Ice Analogs: Implications for Biorelevant Nitrogen Heterocycles in Ryugu and Bennu

The Abundance And Emission Of PAHs From The Local To Early Universe