Gas Giants Archives

The plots of stellar metallicity ([Fe/H]) versus planetary orbital period for all transiting planets from the NASA exoplanet archive. Tranet stands for transiting planet. The transiting planets are split into four groups based on the multiplicity of their systems and are placed on four different panels. The two dotted vertical lines split the metallicity range into three metallicity regions, namely, sub-solar, solar, and super-solar. While low-multiplicity systems are evenly distributed across hosts of all metallicities there is a paucity of high-multiplicity systems around hosts of high metallicity indicating the effect of cold Jupiters on the inner planet multiplicity. -- astro-ph.EP

Exoplanets, -moons, -comets, Gas Giants, Habitable Zones, Icy Worlds, Status Report, Water/Hycean Worlds & Oceanography

Constraining Planetary Formation Models Using Conditional Occurrences of Various Planet Types

by Keith CowingFebruary 28, 2024February 28, 2024

We report the conditional occurrences between three planetary types: super-Earths (m sin i < 10 M⊕, P < 100 days), warm Jupiters (m sin i > 95 M⊕, 10 < […]

Maps of the ring’s flux and brightness temperature as functions of ring radius and wavelength derived from the MIRI observations. The radial extent of the three main rings are shown at the far right of each plot (the Cassini Division is situated between the A and B rings). Note that the brightness temperature is more useful on the right-hand side of the figure, where thermal emission dominates over reflected sunlight. The brightness temperature rapidly increases at short wavelengths because of the increasing contribution of reflected sunlight. Narrow spectral features in the regions indicated by the shaded bands around 8 µm, 12 µm and 14µm are due to stray light from Saturn, but the bright line at 9.2 µm is due to the presence of highly crystalline water ice throughout the ring. -- astro-ph.EP

Gas Giants, Icy Worlds, Imaging & Spectroscopy, Press Release, Saturn

Water-Ice Dominated Spectra of Saturn’s Rings and Small Moons from JWST

by Keith CowingFebruary 27, 2024February 27, 2024

JWST measured the infrared spectra of Saturn’s rings and several of its small moons (Epimetheus, Pandora, Telesto and Pallene) as part of Guaranteed Time Observation program 1247.

Observed UCD candidates on a zoomed Gaia MG - G − J and G − GRP diagrams: UCDs are coloured by their obtained spectral type, as explained in Sect. 3. The two circled UCDs have peculiar colours (see text). Subdwarfs candidates are represented by crosses (see Sect. 4.1). Peculiar objects are represented by triangles (Sect. 4.2). The UCDs with common parallaxes and proper motions with another system are represented by diamonds (see Sect. 4.3) and those in (potentially) unresolved binary systems by squares (Sect. 4.4). The grey points are the sources from the Gaia Catalogue of Nearby Stars, with a RUWE < 1.4. The insets illustrate the locus of our sample on entire GaiaCatalogue of Nearby stars colour-absolute magnitude diagrams. -- astro-ph.SR

Astronomy & Telescopes, Brown Dwarfs, Exoplanets, -moons, -comets, Gas Giants, Imaging & Spectroscopy, Status Report, Stellar Cartography

Near-infrared Spectroscopic Characterisation Of Gaia Ultra-cool Dwarf Candidates; Spectral Types And Peculiarities

by Keith CowingFebruary 16, 2024February 16, 2024

Context: The local census of very low-mass stars and brown dwarfs is crucial to improving our understanding of the stellar-substellar transition and their formation history. These objects, known as ultra-cool […]

Maps of distribution of planets for each planet Type in the HESTIA Milky Way–Analogue for stars with M‹ “ 1M@. The assignment is based on the NEmbryo “ 50 NGPPS population. (a) Face-on view. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Gas Giants, Status Report, Stellar Cartography

Populating The Milky Way: Characterising Planet Demographics by Combining Galaxy Formation Simulations and Planet Population Synthesis Models

by Keith CowingFebruary 15, 2024February 15, 2024

Stellar populations and their distribution differ widely across the Galaxy, which is likely to affect planet demographics.

Forward modelled spectrum for candidate HD 106315 c, binned to R=50 from 0.5-4.5 𝜇m. Molecular absorption components are shown at the binned resolution of the final spectrum. Also shown are the total contributions to the final spectrum from CIA (between H2-H2 and H2-He) and Rayleigh scattering (all atmospheric molecules), with the final spectrum shown in black. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Gas Giants, Imaging & Spectroscopy, Status Report

Cool Gaseous Exoplanets: Surveying The New Frontier With Twinkle

by Keith CowingFebruary 14, 2024February 14, 2024

Cool gaseous exoplanets (1.75 R⊕<Rp<3 RJ, 200 K <Teq<1000~K) are an as-yet understudied population, with great potential to expand our understanding of planetary atmospheres and formation mechanisms.

Contours for the ratio rH/rT of the two radii of circumplanetary disk. The red dashed line denotes the ratio rH/rT = 1. The area to the right of the red dashed line with rH/rT > 1 is favourable for moon’s survival and the area to the left with rH/rT < 1 is unfavourable for moon’s survival. -- astro-ph.EP

Exoplanets, -moons, -comets, Gas Giants, Imaging & Spectroscopy, Magnetic Fields, Electromagnetism, bioelectricity,, Status Report

Magnetic Field Of Gas Giant Exoplanets And Its Influence On The Retention Of Their Exomoons

by Keith CowingFebruary 13, 2024February 13, 2024

We study the magnetic and tidal interactions of a gas-giant exoplanet with its host star and with its exomoons, and focus on their retention. We briefly revisit the scaling law […]

Artistic representation of an exoplanet whose water ice on the surface is increasingly vaporizing and forming an atmosphere during its approach to the central star of the planetary system. This process increases the measured planetary radius compared to the value the planet would have at its place of origin. CREDIT Thomas Müller (MPIA)

Astronomy & Telescopes, Exoplanets, -moons, -comets, Gas Giants, Press Release, Water/Hycean Worlds & Oceanography

Migration Solves An Exoplanet Puzzle

by Keith CowingFebruary 9, 2024February 9, 2024

Ordinarily, planets in evolved planetary systems, such as the Solar System, follow stable orbits around their central star. However, many indications suggest that some planets might depart from their birthplaces […]

Maps of the wavelength dependent optical depth (on a log scale), with optical depths of 0.1, 1.0 and 10 indicated by dotted/solid/dashed line respectively. We compare the optical depth profiles for an R=10 km, ρ =2 g cm−3 , JWST Ice ver. A cometary composition impact at three different points in time, 1 year (A), 5 years (C), and 25 years (C - steady-state) after impact, with our unperturbed HD209458b reference model (D). To emphasise how the opacity of the atmosphere varies time we also include, on our steady-state opacity map, the 1 year (green), 5 year (blue), 25 year (red) and reference (orange) τ = 1 surfaces as light shading. Note the significant effect that the addition of cometary material has had on the optical depth, in particular how an optical depth of one is reached at lower pressures, averaging ∼ 10−2 bar at steady-state vs ∼ 10−1 bar in the unperturbed model, helping to explain the difference in the transmission spectra seen in Figure 8. -- astro-ph.EP

Comets and Asteroids, Exoplanets, -moons, -comets, Gas Giants, Imaging & Spectroscopy, Impact events, Jupiter, Status Report

The Impact Of Cometary Impacts On The Chemistry, Climate, And Spectra Of Hot Jupiter Atmospheres

by Keith CowingFebruary 9, 2024February 9, 2024

Impacts from icy and rocky bodies have helped shape the composition of solar system objects, for example the Earth-Moon system, or the recent impact of comet Shoemaker-Levy 9 with Jupiter. […]

Green triangles show an estimate of the heavyelement content (MZ ) of GEMS from planetary interior models (Thorngren et al. 2016) compared to the Class II disk dust mass (Md) estimates as orange squares (Manara et al. 2022) and the median (and 1-σ) trend seen in the Lupus sample (Ansdell et al. 2016). The green arrows show the approximate expected disk dust masses required to form the green triangles assuming 10% formation efficiency (Liu et al. 2019b). The red line shows the range of dust masses for Class 0 and I disks from Tychoniec et al. (2020). Takeaway: The formation of GEMS necessitates disks with many 100s of M⊕ of heavy-elements. This could be achieved by anomalously massive Class II disks with underestimated dust masses, or Class 0/I disks. -- astro-ph.EP

Astronomy & Telescopes, Brown Dwarfs, Exoplanets, -moons, -comets, Gas Giants, Imaging & Spectroscopy, Status Report

Searching For Giant Exoplanets Around M-dwarf Stars (GEMS) I: Survey Motivation

by Keith CowingFebruary 9, 2024February 9, 2024

Recent discoveries of transiting giant exoplanets around M-dwarf stars (GEMS), aided by the all-sky coverage of TESS, are starting to stretch theories of planet formation through the core-accretion scenario. Recent […]

Distribution of eccentricities for all planets more massive than 0.3 MJ interior to the snow line (left panels) and exterior to the snow line (right panels). For the top two panels, both the shade and the size of the plotted data are logarithmically proportional to the planet mass, where dark green indicates a low mass and light green indicates a high mass. The bottom two panels show the histograms of the eccentricity data appearing in the top two panels. -- astro-ph.EP

Astrochemistry, Astrogeology, Exoplanets, -moons, -comets, Gas Giants, Habitable Zones, Status Report, Water/Hycean Worlds & Oceanography

Eccentricity Distribution Beyond the Snow Line and Implications for Planetary Habitability

by Keith CowingFebruary 7, 2024February 7, 2024

A fundamental question in the study of planetary system demographics is: how common is the solar system architecture?

Gas Giants

Constraining Planetary Formation Models Using Conditional Occurrences of Various Planet Types

Water-Ice Dominated Spectra of Saturn’s Rings and Small Moons from JWST

Near-infrared Spectroscopic Characterisation Of Gaia Ultra-cool Dwarf Candidates; Spectral Types And Peculiarities

Populating The Milky Way: Characterising Planet Demographics by Combining Galaxy Formation Simulations and Planet Population Synthesis Models

Cool Gaseous Exoplanets: Surveying The New Frontier With Twinkle

Magnetic Field Of Gas Giant Exoplanets And Its Influence On The Retention Of Their Exomoons

Migration Solves An Exoplanet Puzzle

The Impact Of Cometary Impacts On The Chemistry, Climate, And Spectra Of Hot Jupiter Atmospheres

Searching For Giant Exoplanets Around M-dwarf Stars (GEMS) I: Survey Motivation

Eccentricity Distribution Beyond the Snow Line and Implications for Planetary Habitability

Perseverance Astrobiology Droid Has Completed A Martian Marathon

Machine Learning And Deep Learning For Exoplanet Detection And Atmospheric Characterization With JWST And The Upcoming Ariel Mission

Bioleaching Of Critical Trace Metals By Sphingomonas Desiccabilis: Substrate-driven Selectivity In Earth And Space Analogues

TESS Reveals The Puffiest Exoplanets Ever Found

An Agnostic Machine Learning Model of Photosynthetic Habitability