rocky planet Archives - Page 2 of 5 - Astrobiology

Overview of our models for gas disk and particles evolution in different disk regions. The blue and yellow particles represent silicates with and without refractory carbon. The light blue particles represent icy pebbles. The pink particles show the oxygen atoms which are formed by the destruction of oxygen molecules because of the FUV radiation which is described as red arrows. The light blue dashed line is the snow line. Icy pebbles enclosing many small silicates drift to the snow line (blue dashed line) from the outer region. Orange upper and lower layers are FUV-exposed regions, where oxygen atoms exist. -- astro-ph.EP

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Habitable Zones, Imaging & Spectroscopy, Interstellar, Status Report

Effect of Different Stickiness Between Icy and Silicate Particles on Carbon Depletion in Protoplanetary Disks

by Keith CowingOctober 12, 2024October 12, 2024

Earth and other rocky bodies in the inner Solar System are significantly depleted in carbon compared to the Sun and interstellar medium (ISM) dust.

A small rocky exoplanet -- Grok via Astrobiology.com

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Status Report, Water/Hycean Worlds & Oceanography

Rocky Worlds Director’s Discretionary Time (DDT) Selects Its First Targets

by Keith CowingSeptember 21, 2024September 21, 2024

The Rocky Worlds DDT Program will use JWST to search for atmospheres around a dozen nearby M-dwarf exoplanets while using HST to characterize activity in the host stars. Over the […]

Schematic of the 1D thermal evolution model used in this work. 𝑄𝑅 is the radiated flux, 𝑄𝑀𝑂 is the heat flux from the magma ocean, 𝑄𝑀𝑆 the heat flux from the magma mush, 𝑄𝑆 the flux from solid rock and 𝑄𝑐 the flux from the core. 𝑄𝐻 is the heat removed from the day-side and added to the night-side when we include horizontal heat transport. 𝑄𝑇 is the tidal heating when tidal dissipation is included in the model. The light blue line is the geotherm of the mantle while the line "L" (dark blue line) is the mantle liquidus and "S" (green line) is the mantle solidus. The pressure increases in the downward direction while the temperature increases to the right. -- astro-ph.EP

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Habitable Zones, Lava / magma ocean / Volcanic Worlds, Status Report, Water/Hycean Worlds & Oceanography

Thermal Evolution Of Lava Planets

by Keith CowingSeptember 20, 2024September 20, 2024

Rocky planets are thought to form with a magma ocean that quickly solidifies. The horizontal and vertical extent of this magma ocean depends on the interior thermal evolution of the […]

Upper panels: The peak hydrogen envelope mass fraction at the end of accretion, before any mass loss, shown in colour for the slow, medium and fast host star rotators. The time when 90% of the envelope mass is lost due to solar XUV radiation is shown in white contour lines in Myr. Lower panels: The atomic composition of the outgassed atmospheres of the slow, medium and fast rotator simulations at 300 Myr. Values of R/O < 1 (blue) indicate an atmosphere with free oxygen, a value of R/O=1 (green) imply sufficient oxygen to oxidise H to H2O and C to CO2, and values of R/O > 1 (red) indicate reducing conditions (see definition of R/O in equation 8). The white contour lines in the lower panels show a value of R/O = 1.3. The patch of R/O=0 present for the slow rotator is due to the perseverance of the envelope for those high planetary masses even after 300 Myr, with the magma ocean still providing a significant pressure of free oxygen. -- astro-ph.EP

Astrochemistry, Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Habitable Zones, Lava / magma ocean / Volcanic Worlds, Meteorites & Asteroids, Status Report, Water/Hycean Worlds & Oceanography

Evolution of Gas Envelopes and Outgassed Atmospheres of Rocky Planets Formed via Pebble Accretion

by Keith CowingSeptember 18, 2024September 18, 2024

We present here results of numerical simulations of the formation and early evolution of rocky planets through pebble accretion, with an with an emphasis on hydrogen envelope longevity and the […]

Astrochemistry, Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Press Release

JWST Thermal Emission of the Terrestrial Exoplanet GJ 1132b

by Keith CowingAugust 28, 2024August 27, 2024

We present thermal emission measurements of GJ 1132b spanning 5–12 um obtained with the Mid-Infrared Instrument Low-Resolution Spectrometer (MIRI/LRS) on the James Webb Space Telescope (JWST).

Number densities of condensate droplets and gas molecules, and their respective molecular weights, as a function of height R/Rp for the atmosphere shown in Figure 8 with Kzz = 1×104 . Left: Numbers of dots at each height in the atmosphere represent the relative number densities of droplets, and the symbol sizes are proportional to droplet sizes. Right: Numbers of dots represent the relative number densities of molecules. In both plots, colors indicate molecular weights at each height (note different color scales in the two panels). Curves for absolute number densities of droplets (left) and gas molecules (right) are overlain for comparison. -- astro-ph.EP

Astrogeology, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Status Report, Water/Hycean Worlds & Oceanography

Phase Equilibria of Sub-Neptunes and Super-Earths

by Keith CowingAugust 22, 2024

We investigate the consequences of non-ideal chemical interaction between silicate and overlying hydrogen-rich envelopes for rocky planets using basic tenets of phase equilibria. Based on our current understanding of the […]

Rocky planet formation in compact disks around M dwarfs -- NASA

Exoplanets, -moons, -comets, Status Report

Rocky Planet Formation In Compact Disks Around M Dwarfs

by Keith CowingAugust 5, 2024August 5, 2024

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 […]

Mass-radius diagram for WASP-132c. The lines show the massradius relation for a pure water model (blue), an Earth-like model (green), and a pure-iron model (gray). The other exoplanets are taken from the PlanetS catalouge (Otegi et al. 2020). -- astro-ph.EP

Astrogeology, Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Gas Giants, Imaging & Spectroscopy, Status Report

Refining the WASP-132 Multi-planetary System: Discovery of a Cold Giant Planet and Mass Measurement of a hot Super-Earth

by Keith CowingJune 27, 2024June 27, 2024

Hot Jupiters generally do not have nearby planet companions, as they may have cleared out other planets during their inward migration from more distant orbits.

Eccentricity distribution of planets with measured radii of 1.5 − 4R⊕ and orbital periods of ≲ 50 days around M dwarfs with Teff = 3000 − 3900 K. Only planets with measured eccentricities are shown. The color contour represents the effective temperature of a planet-hosting M dwarf. The four close-in, sub-Neptunes validated in this study are shown as red stars. astro-ph.EP

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

The Discovery and Follow-up of Four Transiting Short-period Sub-Neptunes Orbiting M dwarfs

by Keith CowingMay 22, 2024May 22, 2024

Sub-Neptunes with 2−3R⊕ are intermediate in size between rocky planets and Neptune-sized planets. The orbital properties and bulk compositions of transiting sub-Neptunes provide clues to the formation and evolution of […]

The mass and radius of TOI-1450Ab (black star) compared to both interior composition models from Zeng et al. (2019) (colored dashed lines) and other exoplanets with mass and radius errors < 20% from TEPCat (gray points). Earth and Venus are also included for reference. - astro-ph.EP

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

Early Results From The HUMDRUM Survey: A Small, Earth-mass Planet Orbits TOI-1450A

by Keith CowingMay 20, 2024May 20, 2024

M dwarf stars provide us with an ideal opportunity to study nearby small planets. The HUMDRUM (HUnting for M Dwarf Rocky planets Using MAROON-X) survey uses the MAROON-X spectrograph, which […]