Habitable Zone Archives

This plot shows currently known exoplanets, with different categories highlighted. Roman will help fill in the bottom-right of the plot by finding small worlds in large orbits. NASA’s Goddard Space Flight Center

Astrochemistry, Astronomy & Telescopes, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Gas Giants, Ice Giant, Imaging & Spectroscopy, Press Release

NASA’s Roman Mission Preps to Unveil New Populations of Faraway Worlds

by Keith CowingMay 29, 2026May 29, 2026

NASA’s Nancy Grace Roman Space Telescope is poised to make a major leap in the hunt for worlds outside our solar system, known as exoplanets. Scientists expect the mission to […]

Left: HZ and planetary orbits in the HD 20794 system, where the orbits are labeled by planet designation. The scale of the figure is 2.9 AU along each side. Right: Variation in incident flux received by HD 20794 d during one complete orbit. For both panels, the extent of the HZ is shown in green, where light green and dark green indicate the CHZ and OHZ, respectively. -- astro-ph.EP

Exoplanets, -moons, -comets, Habitable Zones, Status Report, Stellar Cartography

Dynamical Stability and Habitability in the HD 20794 System

by Keith CowingMay 28, 2026May 28, 2026

The Keplerian orbit of a terrestrial planet can be a significant driver in the evolution of surface conditions, as well as influencing the overall dynamics of the system.

The Investigating Mars at Three Sites Campaign would visit three different locations on Mars. Source NASEM, A Science Strategy for the Human Exploration of Mars (The National Academies Press, Washington, DC, 2025), https://doi.org/10.17226/28594.

AI - Data - Apps - Cybernetics, Analog Studies, Arctic / Antarctic / Alpine, Astronauts and Explorers, Away Teams & Field Reports, Caves, Craters, Mountains, Subsurface, Lava Tubes, Desert Worlds, Exploration Gear & Tech, Habitable Zones, Mapping, Geodesy, Cartography, Bathymetry, Mars, Missions & Hardware, Planetary Protection & Biosafety, Polar / Alpine Expeditions, Robotics/Rovers/UAVs, Sample Return, Space Physiology & Medicine, Status Report

Highlighting A Science Strategy For Human Exploration Of Mars

by Keith CowingMay 26, 2026May 26, 2026

A Science Strategy for Human Exploration of Mars, charts a bold, scientifically based blueprint for humanity’s greatest cosmic adventure—sending explorers to Mars to answer the universe’s most profound questions: Is […]

Conceptual framework of vertically stratified carbon cycling and microbial succession driven by physiological trade-offs in shelf sediments. Organic carbon (OC) reactivity and microbial community structure undergo profound transitions with sediment depth. In surface sediments, Bacteria (blue) drive a transient mineralization hotspot by rapidly consuming labile OC, whereas Archaea (pink) dictate the long-term fate and reactivity of the buried recalcitrant OC pool over geological timescales. These transition of OC degradation and microbial succession are underpinned by fundamental physiological trade-offs: whereas Bacteria prioritize rapid growth (G) with high energy investment near the surface, Archaea, primarily Bathyarchaeia, allocate more energy toward maintenance (M) and adaptation (A) by minimizing their growth rates in the deep subsurface. -- biorxiv.org

Caves, Craters, Mountains, Subsurface, Lava Tubes, Extremeophiles and Extreme Environments, Genomics, Proteomics, Bioinformatics, Habitable Zones, Microbiology & Virology, Status Report

Physiological Trade-offs Drive The archaeal Dominance And Carbon Turnover In Deep Subsurface

by Keith CowingMay 25, 2026May 25, 2026

Marine sediments host a vast deep biosphere, yet how microorganisms persist under severe energy limitation and govern long-term organic carbon (OC) preservation remains poorly understood.

ExoCAM simulations of Earth from the present up to 2.0 Gyr in the future, assuming CO2 remains fixed at 400 ppm. The top row shows surface temperature, the middle row shows precipitation minus evaporation, and the bottom row shows the habitability metric developed by Woodward et al. (2025) (Eqs. (D1) and (D2)). All quantities are 20-year averages after the model has reached a steady-state. Increases in temperature due to a brightening sun cause an increase in habitability up to 1.5 Gyr due to the greening of the poles, but habitability decreases significantly by 2.0 Gyr as Earth becomes too hot for complex vegetative life. This corresponds to a weak temperature dependence of weathering, in which Earth’s CO2 levels do not change even as the climate warms (c.f., Graham et al., 2024). -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Desert Worlds, Gaia - Planetary Perspectives, Imaging & Spectroscopy, Space Agriculture, Status Report, Terraforming & Geoengineering, Water/Hycean Worlds & Oceanography

Maximum Lifetime Of The Vegetative Biosphere

by Keith CowingMay 23, 2026May 23, 2026

We use a three-dimensional model to calculate steady-state climates at various intervals in Earth’s future, across a parameter space of increasing insolation and decreasing CO2 mixing ratio.

Main categories of extremophiles. This illustration depicts the 10 most common extremophile types, highlighting their defining physicochemical stressors and representative natural environments. -- Briefings in Bioinformatics

AI - Data - Apps - Cybernetics, Analog Studies, Arctic / Antarctic / Alpine, Away Teams & Field Reports, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Caves, Craters, Mountains, Subsurface, Lava Tubes, Cryobiology, Desert Worlds, Extremeophiles and Extreme Environments, Fossils & Paleontology, Genomics, Proteomics, Bioinformatics, Habitable Zones, Icy Worlds, Mapping, Geodesy, Cartography, Bathymetry, Nomenclature, Systematics, Natural History, Status Report

Decoding Extremophiles: Insights From Bioinformatics, Machine Learning, And Data-driven Approaches

by Keith CowingMay 22, 2026May 23, 2026

Life thrives in Earth’s most inhospitable environments, from boiling hydrothermal vents to hypersaline lakes and frozen polar deserts, thanks to the remarkable adaptations of extremophilic microorganisms.

Schematic cross sections of Earth and Mars, showing the major internal components and atmospheric components, to scale. For simplicity, oceanic and continental crust for Earth are not distinguished, nor is the interior structure of Earth’s mantle shown. -- astro-ph.EP

Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Desert Worlds, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Mars, Origin & Evolution of Life, Status Report, Terraforming & Geoengineering, Water/Hycean Worlds & Oceanography

Mars As An Exoplanet: Lessons From A Planet At The Edge Of Habitability

by Keith CowingMay 20, 2026May 20, 2026

Mars is the Solar System’s canonical small, rocky planet that transitioned from early geologic activity and surface liquid water to a cold and arid planet with a thin, cold, CO2-dominated […]

Radial velocity data for GJ 3378. Top: the combined RV time series. The orbit model is shown as a dashed line. Middle: RV residuals to a 1-planet model. Bottom: RVs phase-folded to the period of the exoplanet. Phase-binned RVs are shown as squares. -- astro-ph.EP

Astronomy & Telescopes, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release

A Revised Mass and Period for the Habitable Zone super-Earth GJ 3378b: A Planet Straddling the Cosmic Shoreline

by Keith CowingMay 19, 2026May 19, 2026

The nearby (d=7.7 pc) M4V star GJ~3378 is a target of our radial velocity (RV) exoplanet survey of fully convective stars in the Solar neighborhood with the near-infrared spectrograph HPF […]

Schematic illustration of occurrence rate of inhabited planets versus observational detectability for JWST transmission spectroscopy

Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report

The First Remotely Detected Biosignature May Not Be the Most Common: Implications for JWST and HWO

by Keith CowingMay 19, 2026May 19, 2026

The first detected member of a new astronomical class is often not representative of the underlying population, but instead reflects the selection effects of the observing technique that found it.

Compositional analyses of the fog microbiome and partition of the bulk aerobiome. (A) Fog water bacterial community composition in 32 sequential fogs was determined by 16S ribosomal gene sequencing with phylogenetic assignments to the level of genus according to the SILVA database. -- Environmental Microbiology

Atmospheres, Climate, Weather, Biophysics, Biosignatures & Paleobiology, Habitable Zones, Microbiology & Virology, Press Release, Sample Return

Bacteria Live In Fog Droplets And Clear Toxins From Earth’s Air

by Keith CowingMay 18, 2026May 18, 2026

What if fog isn’t just misty air, but a living ecosystem?

Habitable Zone

NASA’s Roman Mission Preps to Unveil New Populations of Faraway Worlds

Dynamical Stability and Habitability in the HD 20794 System

Highlighting A Science Strategy For Human Exploration Of Mars

Physiological Trade-offs Drive The archaeal Dominance And Carbon Turnover In Deep Subsurface

Maximum Lifetime Of The Vegetative Biosphere

Decoding Extremophiles: Insights From Bioinformatics, Machine Learning, And Data-driven Approaches

Mars As An Exoplanet: Lessons From A Planet At The Edge Of Habitability

A Revised Mass and Period for the Habitable Zone super-Earth GJ 3378b: A Planet Straddling the Cosmic Shoreline

The First Remotely Detected Biosignature May Not Be the Most Common: Implications for JWST and HWO

Bacteria Live In Fog Droplets And Clear Toxins From Earth’s Air

A Martian Horizon Last Monday Afternoon

Habitable-zone Earths At The Detection Frontier: Measured Completeness And False-alarm Rate Of A Transit Pipeline For The PLATO M-dwarf Sample

A Homogeneous Survey Of JWST MIRI Transmission Spectra Of 10 Exoplanets

Retrieving Ocean Glint Reflectance Signatures From Directly Imaged Earth-like Exoplanets

Analytical Platform (Microsampling, Catapulting, Trapping, and LIBS) for the Characterization of Discrete Domains in Samples of Astrochemical Interest