Earth-like exoplanet Archives

Located about 39 light-years from Earth, the TRAPPIST system resembles a miniature version of our solar system: The star, an ultracool red dwarf, and all its planets would comfortably fit inside the orbit of planet Mercury. Credit NASA, ESA, CSA, STScI, Joseph Olmsted (STScI)

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release, Titan, TRAPPIST-1

A New Look At TRAPPIST-1e, An Earth-sized, Habitable-zone Exoplanet

by Keith CowingDecember 5, 2025December 5, 2025

Of the seven Earth-sized worlds orbiting the red dwarf star TRAPPIST-1, one planet in particular has attracted the attention of scientists, because it orbits the star within the “Goldilocks zone” […]

Top: Same as Figure 3, but for TIC 80127634, which is a G star that exhibits high amplitude variations that is used for the water loss simulations. Left: Orbit architecture of a hypothetical Earth-like planet in a circular orbit within the HZ of TIC 80127634. The black circle shows the simulated planet orbit. The light shaded region shows the CHZ and the dark shaded region shows the larger bounds of the OHZ. Right: Percent change in the incident flux received by the hypothetical Earth-like planet. -- astro-ph.EP

Exoplanets, -moons, -comets, Habitable Zones, Space Weather & Heliophysics, Status Report, Stellar Cartography

Planetary Habitability Under The Light Of A Rapidly Changing Star

by Keith CowingNovember 27, 2025

Planetary atmospheric energy budgets primarily depend on stellar incident flux. However, stellar variability can have major consequences for the evolution of planetary climates.

Flux with central regions masked (10 µm; upper row), and corresponding asymmetric flux relative to the planet flux Fp (lower row), following the format of Fig. 6. This masking emphasizes resonant structures, and all maps are shown within a spatial scale of ∼ 2 ap. Asymmetric flux panels follow the approach of Fig. 11 in Defrère et al. (2010).-- astro-ph.EP

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

Resonant Structures In Exozodiacal Clouds Created By Exo-Earths In The Habitable Zone Of Late-type Stars

by Keith CowingNovember 26, 2025November 26, 2025

Earth-like exoplanets can create resonant structures in exozodiacal dust through mean motion resonances (MMRs).

The magnetopause standoff distance of a planet orbiting our stellar sample. The theoretical decay of the Parker model (blue) and that measured in the solar system (red) are used in the estimations for Case 1 (left panels) and for Case 3, fast wind (right panels). In the upper (bottom) panels the planet is orbiting the outer (inner) radius of the HZ. The gray dashed line represents Earth’s early magnetosphere. The results of Vidotto et al. (2013) were added for comparison. -- astro-ph.SR

Habitable Zones, Imaging & Spectroscopy, Origin & Evolution of Life, Radiation, Space Weather & Heliophysics, Status Report

The Impact Of Stellar Winds And Tidal Locking Effects On The Habitability Of Earth-like Exoplanets Around M Dwarf Stars

by Keith CowingOctober 28, 2025October 28, 2025

We present an assessment of the effects of stellar wind magnetic and mechanical components on the habitability of Earth-like exoplanets orbiting the inner and outer radii of the habitable zone […]

The distribution maps of clouds for longitudes from –180° to 180° and latitudes from –90° to 90° for the models of the Earth (P = 1 d) (a) and the exo-Earth (P = 100 d) -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report

Spectra Of Earth-like Exoplanets With Different Rotation Periods

by Keith CowingSeptember 24, 2025September 24, 2025

We investigate the spectra of Earth-like planets but with different axial rotation periods.

Selected examples of observed polarized Earthshine spectra, along with corresponding simulations of reflected and polarized light, as presented in Appendix B. For each spectrum, we include a simulated observation image, fit the power-law slopes γ, and report the RMSE between simulations and observations. -- astro-ph.EP

Planet Earth In Reflected And Polarized light – III. Modeling And Analysis Of A Decade-long Catalog Of Earthshine Observations

by Keith CowingSeptember 22, 2025September 22, 2025

Earthshine observations offer a unique opportunity to study Earth as an exoplanet seen from the Moon. As the Sun-Earth-Moon geometry changes, Earth can be observed as a spatially unresolved exoplanet […]

Earth-like and super Earth planet candidates from (5) are shown in the effective temperature - instellation flux plane. Conservative and optimistic Habitable zones as defined in (5) are shown as green regions. The size of the dots is proportional to the planet’s radius. On the left, the candidates are colored by their reliability against false alarms from (48). On the right they are colored by the false alarm probability as determined by NSTs. Some of the candidates that were previously assigned a high reliability are no longer considered significant, and vice versa. -- astro-ph.EP

Astronomy & Telescopes, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report

Reassessment Of Kepler’s Habitable Zone Earth-like Exoplanets With Data-driven Null-signal Templates

by Keith CowingSeptember 10, 2025

One of the primary mission goals of the Kepler space telescope is to detect Earth-like terrestrial planets in the habitable zone around Sun-like stars.

Earth biosignatures through time and their reflected light spectra. The left subplot shows estimates of Earth’s bulk atmospheric composition through time (advancing from top to bottom), and the figures on the right show the corresponding reflected light spectra considered in this study. Key absorption features for biosignature gases (O3, O2, CH4) and suggested long and short wavelength cutoffs are highlighted (as discussed further in Sections 3 and 4). Adapted from National Academies of Sciences (2021) and LUVOIR and HabEx Final Reports (Gaudi et al., 2020; LUVOIR Team, 2019). -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report

Wavelength Requirements For Life Detection Via Reflected Light Spectroscopy Of Rocky Exoplanets

by Keith CowingJuly 22, 2025July 22, 2025

Searching for signs of life is a primary goal of the Habitable Worlds Observatory (HWO). However, merely detecting oxygen, methane, or other widely discussed biosignatures is insufficient evidence for a […]

Transit spectra of the best fit non-equilibrium 1D model at resolution 200 (black solid line). This is the approximate best fit on the simulated grid of metallicity, C/O and Kzz. Values are respectively 280.7, 90.0 and 106 cm2 .s−1 . It is compare to K2-18 b observation (Madhusudhan et al. 2023) low resolution representation with an offset of -41ppm between NIRISS and NIRSpec data. The contributions of considered molecules are represented with shaded colors. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Habitable Zones, Imaging & Spectroscopy, Press Release

Unraveling The Non-equilibrium Chemistry Of The Temperate Sub-Neptune K2-18 b

by Keith CowingJuly 22, 2025July 22, 2025

The search for habitable, Earth-like exoplanets faces major observational challenges due to their small size and faint signals.

What a terrestrial exoplanet might look like from afar - Astrobiology.com

Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Bathymetry, Status Report

Direct High-Resolution Imaging of Earth-Like Exoplanets

by Keith CowingJune 27, 2025June 27, 2025

We have surveyed all conventional methods proposed or conceivable for obtaining resolved images of an Earth-like exoplanet.

Earth-like exoplanet

A New Look At TRAPPIST-1e, An Earth-sized, Habitable-zone Exoplanet

Planetary Habitability Under The Light Of A Rapidly Changing Star

Resonant Structures In Exozodiacal Clouds Created By Exo-Earths In The Habitable Zone Of Late-type Stars

The Impact Of Stellar Winds And Tidal Locking Effects On The Habitability Of Earth-like Exoplanets Around M Dwarf Stars

Spectra Of Earth-like Exoplanets With Different Rotation Periods

Planet Earth In Reflected And Polarized light – III. Modeling And Analysis Of A Decade-long Catalog Of Earthshine Observations

Reassessment Of Kepler’s Habitable Zone Earth-like Exoplanets With Data-driven Null-signal Templates

Wavelength Requirements For Life Detection Via Reflected Light Spectroscopy Of Rocky Exoplanets

Unraveling The Non-equilibrium Chemistry Of The Temperate Sub-Neptune K2-18 b

Direct High-Resolution Imaging of Earth-Like Exoplanets

Tricorder Tech: New Handheld Device Maps Chemical Composition Using Infrared Light

No Statistically Significant Evidence For A Correlation Between Stellar And planetary Composition

Water Planet Recon: How Accurately Can We Measure Earth Ocean’s Deepest Point?

Webb Reveals A Stunning Panorama Of Star Formation

Deep Learning of SHERLOC Raman Spectra For Facilitating Mars Astromaterial Identification