Exoplanets, -moons, -comets – My WordPress Site

The mass versus orbital distance of currently discovered and characterized exoplanets. Solar system planets are indicated as well. The hexagonal icons, indicating spectroscopic characterization studied done using JWST, are adopted from Espinoza & Perrin (2025). Direct imaging, currently limited to far out and large planets, will have to advance in sensitivity and contrast ratio to reach Earth-like planets. -- astro-ph.EP

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy

Spectral Signatures From The Habitable Zone

by Keith CowingApril 13, 2026April 13, 2026

This work describes the context and approach for the detection of spectroscopic signatures from planets in the habitable zone of nearby stars.

Wind structures for the synchronous and 10:1 SOR simulations, reproduced from fig. 5 of Part I and included here for reference. Columns from left to right show the horizontal distribution of zonal wind, meridional wind, and vertical wind at 0.001 bar. Streamlines indicate the direction of the horizontal flow. Results are shown in the heliocentric frame to more clearly illustrate the wind patterns. Black star-shaped markers indicate the location of the substellar point. The first and second rows show results from the synchronous and 10:1 SOR simulations as examples, with the wind patterns in other simulations being similar. -- astro-ph.EP

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Imaging & Spectroscopy

Three-dimensional Transport-induced Chemistry On Temperate Sub-Neptune K2-18b, Part II: The Combined Effects Of Atmospheric Dynamics And Chemical Reactions

by Keith CowingApril 12, 2026April 12, 2026

PSF-subtracted images of all targets. The observation subarray of each target is indicated. The first seven images are zoomed in to area of 11.0” × 11.0” for clearer view of the central regions. For the last three targets, the small size (4.4” × 4.4”) is due to the choice of the observation subarray. The location of the star PSF center is denoted by the white cross. Sources around LHS 1478, TOI-1468, and TOI-270 are labeled with letters, which are likely background sources. The arrow near HD 260655 indicates a low-S/N identification of possible close companion. We further examined this detection in Section 4.4. North is up and east is to the left. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Stellar Cartography

A Search For Wide-orbit Planets Around M-dwarfs Using Deep MIRI 15-micron Images

by Keith CowingApril 12, 2026April 12, 2026

Plotted here are the Kepler confirmed planets/candidates with Gaia DR2 radius improvements. Selection criteria are main-sequence host-star with temperature 5000-6500 K and planet radius errors less than ±10%. Data source: exoplanet archive (Akeson et al. 2013) (Christiansen et al. 2025) (Thompson et al. 2017) and Gaia DR2 Berger et al. (2020, 2018); Brown et al. (2018); Lindegren et al. (2018). Sub-Panels: (1): 1100+ planets fulfilling the criteria, with gray ellipse showing the typical errors in planet radius and temperature. (2) and (3): Smooth Kernel fit to data. (4): All known transiting Hot Jupiters (Rp > 8 R⊕) which have masses measured from RV surveys (e.g. WASP, HAT, HAT-P, etc.), colored by metallicity ([Fe/H]). also c.f. (Castro-González et al. 2024). -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Stellar Cartography

Exoplanet Orbital Distribution Around FGK Sun-like Host Stars I: Planet Occurrence Rate Derived From The Kepler Mission And Theoretical Interpretations From Planet Formation

by Keith CowingApril 11, 2026April 11, 2026

EXOKYOTO4D -- Kyoto University

AI - Data - Apps - Cybernetics, Astronomy & Telescopes, Exoplanets, -moons, -comets

Release Of The Exoplanet Database “EXOKYOTO3D” And Announcement Of The Extended Version “EXOKYOTO4D”

by Keith CowingApril 10, 2026April 10, 2026

Analog Studies, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Water/Hycean Worlds & Oceanography

The Goldilocks Problem For Detecting Water In Terrestrial Planets: Constraining Water Abundances In The mid-IR With LIFE

by Keith CowingApril 10, 2026April 10, 2026

[L] The detrended and phase-folded RV time series of GJ 1132 b (top) and GJ 1132 c (bottom). Different draws of the Keplerian models from our posterior are superimposed in black. The different colored markers correspond to different RV time series. Binned data points are shown as red squares. [R] Phase-folded and detrended RV time series of LTT 3780 b (top) and LTT 3780 c (bottom). The best-fit Keplerian model is superimposed in black. The different colors and markers correspond to different RV time series. Binned data points are shown as red squares. -- astro-ph.EP

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Water/Hycean Worlds & Oceanography

Super-Earth Masses And Stellar Abundances From NIRPS Reveal Tentative Evidence For Water-rich Formation Around M Dwarfs

by Keith CowingApril 10, 2026April 10, 2026

Model transmission spectra comparing several haze compositions on a GJ 1214b-like planet with a temperate waterrich atmosphere. We model a clear atmosphere as well as atmospheres with Titan-like hazes, water-rich exoplanet hazes, and the insoluble and soluble fractions of water-rich exoplanet hazes. Existing Hubble and JWST data of GJ 1214b are also plotted for reference. The top panel displays the full modeled wavelength range of 0.3 to 14.0 µm, and the bottom panels zoom into the wavelength regions with observational data. -- astro-ph.EP

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Water/Hycean Worlds & Oceanography

Hydrolyzed Hazes on Water-rich Exoplanets: Optical Constants and Detectability

by Keith CowingApril 10, 2026April 10, 2026

Main plot: mass-radius plot of well-studied exoplanets from TepCat in between 1-20 Earth masses and 1-4 Earth radii. Some theoretical mass-radius curves are shown for comparison. Although a subset of planets is below the silicate (i.e. pure rock) curve and can be identified as rocky planets, a larger proportion of the planets is above this curve. In particular, they exhibit a clustering in the range of 6-10 Earth masses as shown by the background with 2D probability density contours and shading. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Stellar Cartography

Exoplanet Orbital Distribution Around FGK Sun-like Host Stars II: A Valley In The Orbital Semi-major Axis Distribution Of Sub-Neptunes

by Keith CowingApril 10, 2026April 10, 2026

The Paranal solar ESPRESSO Telescope (PoET)

Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy

First Light For PoET: Shining (sun)Light On Exoplanet Research

by Keith CowingApril 9, 2026April 9, 2026