![Fiducial model generated (synthetic) reflected light spectrum of an Earth-like planet at quadrature (i.e., at a planetary phase angle α = 90°; see Table 1 for fiducial input values). The colored areas indicate the spectral impact of the gas species by showing the difference between the baseline spectrum (black line) and the spectrum obtained if they were absent from the atmosphere. The top of the figure shows the two wavelength ranges considered and their spectral resolving power: red bandpass (λ = [0.87, 1.05] µm, res = 140; see Appendix B) and visible (λ = [0.45, 1] µm, res = 140) + NIR (λ = [1, 1.80] µm, res = 70). The error bars show the nonrandomized, wavelength-independent noise corresponding to specific signal-to-noise ratios (SNR) at the reference wavelengths λ = 0.45 µm for the vNIR range, and λ = 0.88 µm for the red bandpass. --astro-ph.EP](https://i0.wp.com/astrobiology.com/wp-content/uploads/2024/06/Influence-of-Orbit-and-Mass.png?resize=1200%2C720&ssl=1)
Survey strategies for upcoming exoplanet direct imaging missions have considered varying assumptions of prior knowledge. Precursor radial velocity surveys could have detected nearby exo-Earths and provided prior orbit and mass […]
rocky exoplanet
Posted inAstrogeology, Astronomy & Telescopes, Exoplanets, -moons, -comets, Status Report
Rocky Planet Formation In Compact Disks Around M Dwarfs
Rocky planets in compact configurations are the most common ones around M dwarfs. Many disks around very low mass stars (between 0.1 and 0.5 M⊙) are rather compact and small […]
![Comparison of SPECULOOS-3 b with other rocky exoplanets. a) Sizes of host stars and incident stellar flux of known sub-Neptune-sized exoplanets. The size of the symbols scales linearly with the radius of the planet. The background is colour-coded according to stellar size (in units of the Sun’s size), with the ultra-cool dwarf regime shown in orange. The positions of the Solar System terrestrial planets are shown for reference. One can see on this Figure that SPECULOOS-3 b extends the unique planet sample of TRAPPIST-1 to a larger stellar flux. b) SPECULOOS-3 b in the context of other known transiting terrestrial exoplanets (Rp < 1.6R⊕) that are cool enough (Teq < 880 K [80]) to have a dayside made of solid rock (in contrast to hotter magma worlds with molten surfaces). The planets are shown as a function of their radius and their Emission Spectroscopy Metric [62]. They are color-coded as a function of their equilibrium temperature. The shaded green area highlights planetary radii most similar to Earth’s (0.9–1.1 R⊕). The dashed horizontal line represents the threshold of ESM=7.5 recommended by ref. [62] to identify the top targets for emission spectroscopy with JWST. SPECULOOS-3 b is one of the smallest planets amenable to emission spectroscopy with MIRI/LRS. Data from https://exoplanetarchive.ipac.caltech.edu (16th of October 2023). -- astro-ph.EP](https://i0.wp.com/astrobiology.com/wp-content/uploads/2024/06/Detection-Of-An-Earth-sized-Exoplanet.png?resize=1200%2C720&ssl=1)
Posted inAstronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report
Detection Of An Earth-sized Exoplanet Orbiting The Nearby Ultracool Dwarf Star SPECULOOS-3
Located at the bottom of the main sequence, ultracool dwarf stars are widespread in the solar neighbourhood. Nevertheless, their extremely low luminosity has left their planetary population largely unexplored, and […]
![Mass–radius diagram of confirmed exoplanets with mass and radius precision better than 3σ and 10σ, respectively. Planetary parameters (black dots) are taken from the NASA Exoplanet Archive (https://exoplanetarchive.ipac.caltech.edu), and updated to October 2023. HD 73344b is represented by the red dot. The red arrow represents the upper 10σ limit on its mass. Composition models calculated from Aguichine et al. (2021) with a core mass fraction of 30% and various H2O mass fraction (from 10% to 80%) are represented by coloured lines (see text). Composition models calculated from Lopez & Fortney (2014) for a 1 Gyr-old system, Teq,b ∼ 900 K, and an envelope mass fraction fenv = [1, 2, 3, 4, 5] % are shown in gray. For comparison, the relation for an Earth-like composition (32.5% core, 67.5% mantle) from Brugger et al. (2017) is shown by the green dashed curve, and some solar system planets (Venus, the Earth, Uranus and Neptune) are displayed. -- astro-ph.EP](https://i0.wp.com/astrobiology.com/wp-content/uploads/2024/05/A-Low-mass-Sub-Neptune-Planet.png?resize=1200%2C719&ssl=1)
Posted inAstronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Gas Giants, Imaging & Spectroscopy, Status Report
A Low-mass Sub-Neptune Planet Transiting The Bright Active Star HD 73344
Context. Planets with radii of between 2-4 RE closely orbiting solar-type stars are of significant importance for studying the transition from rocky to giant planets.
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Lava / magma ocean / Volcanic Worlds, Status Report
A Secondary Atmosphere On The Rocky Exoplanet 55 Cancri e
Characterizing rocky exoplanets is a central endeavor of astronomy, and yet the search for atmospheres on rocky exoplanets has hitherto resulted in either tight upper limits on the atmospheric mass […]
Posted inAstrogeology, Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report, Water/Hycean Worlds & Oceanography
Observation Uncertainty Effects On The Precision Of Interior Planetary Parameters
Determining compositions of low-mass exoplanets is essential in understanding their origins. The certainty by which masses and radius are measured affects our ability to discern planets that are rocky or […]
Posted inAtmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Status Report, Water/Hycean Worlds & Oceanography
Super-Earths and Earth-like Exoplanets
In the last few years astronomical surveys have expanded the reach of planetary science into the realm of small and dense extrasolar worlds. These share a number of characteristics with […]
Posted inAstrogeology, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release
Webb Hints At A Possible Atmosphere Surrounding Rocky Exoplanet 55 Cancri e
While the planet is too hot to be habitable, detecting its atmosphere could provide insights into the early conditions of Earth, Venus, and Mars.
Posted inAtmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Status Report
The Most Common Habitable Planets III — Modeling Temperature Forcing and Surface Conditions on Rocky Exoplanets and Exomoons
Small rocky planets, as well as larger planets that suffered extensive volatile loss, tend to be drier and have thinner atmospheres as compared to Earth. Such planets probably outnumber worlds […]
Posted inAstrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Status Report
From Stars To Diverse Mantles, Melts, Crusts And Atmospheres Of Rocky Exoplanets
This review is focused on describing the logic by which we make predictions of exoplanetary compositions and mineralogies, and how these processes could lead to compositional diversity among rocky exoplanets.