A team from the University of Bern and the National Centre of Competence in Research (NCCR) PlanetS has developed a machine learning model that predicts potential planetary systems with Earth-like […]
Earth-like Planet
![Odds ratio of the hypotheses that abiogenesis is a fast vs slow process. Each curve represents the odds ratio, computed using Equation 1, as a function of the biosphere’s ultimate lifespan, T - although we have subtracted off the modern epoch to yield remaining time on the x-axis. Previous estimates [1, 8] for the earliest evidence of life yield the dotted and dashed lines, but the new LUCA date of 4.2 Gya [10] greatly improves the odds factor. Indeed, the three solid lines show how the odds are always above 10:1 irrespective of how one chooses T or indeed fairly extreme choices (Carboniferious and Cambrian period) for the earliest civilization on Earth, t ′ I - evident by the circles which denote the minima. -- astro-ph.EP](https://i0.wp.com/astrobiology.com/wp-content/uploads/2025/04/Strong-Evidence-That-Abiogenesis.png?resize=1200%2C721&ssl=1)
Posted inBiochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Habitable Zones, Origin & Evolution of Life, Press Release
Strong Evidence That Abiogenesis Is a Rapid Process on Earth Analogs
The early start to life naively suggests that abiogenesis is a rapid process on Earth-like planets. However, if evolution typically takes ~4Gyr to produce intelligent life-forms like us, then the […]
Posted inAtmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Status Report, Water/Hycean Worlds & Oceanography
Examining the Potential for Methyl Halide Accumulation and Detectability in Possible Hycean-Type Atmospheres
Some sub-Neptune planets may host habitable conditions; for example “Hycean” worlds with H2 envelopes over liquid water oceans can maintain potentially hospitable pressures and temperatures at their surface.
Posted inAtmospheres, Climate, Weather, Exoplanets, -moons, -comets, Habitable Zones, Status Report
Habitable Zone and Atmosphere Retention Distance (HaZARD) Stellar-evolution-dependent Loss Models of Secondary Atmospheres
A major open question in exoplanet research is whether secondary atmospheres are rare around Earth-sized rocky exoplanets. In this work we determine the distance at which an Earth-sized planet orbiting […]
Posted inAstronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report, Stellar Cartography
Searching for Low-Mass Exoplanets Amid Stellar Variability with a Fixed Effects Linear Model of Line-by-Line Shape Changes
The radial velocity (RV) method, also known as Doppler spectroscopy, is a powerful technique for exoplanet discovery and characterization. In recent years, progress has been made thanks to the improvements […]
![Normalised observed spectrum of the star GJ 880 as black dashed line, and best-fit model (synthetic spectrum predicted by the Payne’s ANN for the parameters given in Table 2) as orange solid line. Grey shaded areas indicate the location of the line mask we used. Derived parameters for this star are Teff: 3649 K, log g: 4.8 dex, and [Fe/H]: 0.25 dex -- astro-ph.SR](https://i0.wp.com/astrobiology.com/wp-content/uploads/2025/02/Performance-of-the-Stellar-Abundances.png?resize=1200%2C720&ssl=1)
Posted inExoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, Stellar Cartography
Performance of the Stellar Abundances and Atmospheric Parameters Pipeline Adapted for M Dwarfs I. Atmospheric Parameters from the Spectroscopic Module
M dwarfs are important targets in the search for Earth-like exoplanets due to their small masses and low luminosities. Several ongoing and upcoming space missions are targeting M dwarfs for […]
Posted inAstrogeology, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Press Release, TRAPPIST-1, Venus
TRAPPIST-1 d: Exo-Venus, Exo-Earth or Exo-Dead?
TRAPPIST-1 d is generally assumed to be at the boundary between a Venus-like world and an Earth-like world, although recently published works on TRAPPIST-1 b and c raise concerns that […]
Posted inAstronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report
Effects of Planetary Mass Uncertainties on the Interpretation of the Reflectance Spectra of Earth-like Exoplanets
Atmospheric characterization of Earth-like exoplanets through reflected light spectroscopy is a key goal for upcoming direct imaging missions. A critical challenge in this endeavor is the accurate determination of planetary […]
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Interstellar, Status Report, Water/Hycean Worlds & Oceanography
Eta-Earth Revisited II: Deriving a Maximum Number of Earth-like Habitats in the Galactic Disk
In Lammer et al. 2024, we defined Earth-like Habitats (EH) as rocky planets in the habitable zone of complex life (HZCL) on which Earth-like N2-O2-dominated atmospheres with minor amounts of […]
Posted inAstronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report
Revisiting the Multi-planetary System of the Nearby star HD 20794: Confirmation of a Low-mass Planet in the Habitable Zone of a Nearby G-dwarf
Close-by Earth analogs and super-Earths are of primary importance because they will be preferential targets for the next generation of direct imaging instruments. Bright and close-by G-to-M type stars are […]