June 2024 – Page 3 – My WordPress Site

Peak emission wavelength of a Dyson Swarm as a function of swarm temperature, following Wien’s displacement law, λmax = b/TDS. The shaded regions indicate the approximate wavelength coverage of key infrared observatories: JWST/NIRCam (red band with star hatching, 0.6−5.0 µm ) JWST/MIRI (orange band with slanted hatching, 5.0−28.3 µm) and Roman/Euclid (NIR) (blue band with dotted hatching, 0.5−2.0 µm). For example, a swarm at TDS ∼ 300 K peaks near ∼ 10 µm, within JWST- MIRI’s sensitivity, whereas hotter swarms (TDS ≳ 1000 K) peak in the near-IR range of Euclid and Roman. -- astro-ph.IM

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Comets and Asteroids, Meteorites & Asteroids, Missions & Hardware, Sample Return

An OSIRIS-REx Asteroid Sample Has Surprising Phosphate Content

by Keith CowingJune 27, 2024June 27, 2024

Astrogeology, Biogeochemical Cycles & Geobiology, Biophysics, Caves, Craters, Mountains & Lava Tubes, Extremeophiles and Extreme Environments, Imaging & Spectroscopy, Io, Missions & Hardware

Volcano World Update: Lava Lakes On Io

by Keith CowingJune 27, 2024June 27, 2024

Upper mass limits for a potential lunar companion to β Pic b as a function of orbital period. The color is proportional to the density of MCMC posterior samples, and the solid curves indicate the 68%, 95%, and 99.7% confidence intervals. The upper panel covers longer orbital periods (≲ 1450 days, within the dynamical stability limit), where companions more massive than ∼ 0.5 MJup (∼ 60 M⊕) are excluded. The dashed line marks the Earth–Moon mass ratio scaled to β Pic b, and the solid green curve shows the moon/binary planet boundary from Stern & Levison (2002), which marks the theoretical separation between large moons and binary planetary systems based on mass ratios and orbital stability criteria. The lower panel zooms in on short orbital periods (≲ 50 days), where the constraints are weaker. The dashed line indicates the Pluto–Charon mass ratio, while the solid green curve again shows the Stern & Levison (2002) moon/binary planet boundary. -- astro-ph.EP

Extinction events, Fossils & Paleontology, Gaia - Planetary Perspectives, Impact events

Ammonites’ Fate Sealed By The Meteor Impact That Wiped Out The Dinosaurs

by Keith CowingJune 27, 2024June 27, 2024

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology

Open-Ended Versus Bounded Evolution: Mineral Evolution As A Case Study

by Keith CowingJune 26, 2024June 26, 2024

Astrochemistry, Astrogeology, Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, SETI & Technosignatures, Terraforming & Geoengineering, TRAPPIST-1

Telltale Greenhouse Gases Could Signal Alien Terraforming Activity

by Keith CowingJune 26, 2024June 26, 2024

The transit of Venus across the sun on 5 June 2012 observed in 5 SDO channels. The black dots represent the path of Venus and do not depict the actual planet size or the cadence at which it was observed. Top row shows the images obtained in 6173Å and 1700Å channels; bottom row shows the images obtained in 304Å, 171Å, and 94Å channels respectively. -- astro-ph.EP

Exoplanets, -moons, -comets

Three Potential Super-Earths Discovered Around Nearby Star HD 48 948

by Keith CowingJune 26, 2024September 18, 2025

TESS PDC-SAP flux measurements extracted from the 2-min cadence data of TOI-7166. The target was observed in sector 82. The blue points show the 2-min data, and the red points show the 20-min binned data. The transit locations of TOI-7166 b are shown with black arrows and zoom boxes. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Habitable Zones, Imaging & Spectroscopy, Mars, Venus, Water/Hycean Worlds & Oceanography

Interior Convection Regime, Host Star Luminosity, And Predicted Atmospheric CO2 Abundance In Terrestrial Exoplanets

by Keith CowingJune 26, 2024June 26, 2024

TOP: Heat map plots illustrating detection strength as a function of normalized exposure time and varying resolving abundance at varying Earth H2O abundances with 2 spectral points permitted at each bandwidth. lnB≥5 is a strong detection, 2.5≤lnB≤5 is a weak detection, and lnB≤2.5 is unconstrained. A modern abundance of H2O is considered to be 3×10−3 . With two spectral points regardless of bandwidth, H2O detectability is low, requiring higher abundances. BOTTOM: Heat map plots illustrating detection strength as a function of normalized exposure time and varying resolving abundance at varying Earth H2O abundances with 3 spectral points permitted at each bandwidth. lnB≥5 is a strong detection, 2.5≤lnB≤5 is a weak detection, and lnB≤2.5 is unconstrained. Note that the y-axis is cropped to 3.84, to more directly compare to Figure 2 which caps at 4.0. The key factor to photometric H2O detection is spectral point quantity. -- astro-ph.EP

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

Revising Properties of Planet-Host Binary Systems. IV. The Radius Distribution of Small Planets in Binary Star Systems is Dependent on Stellar Separation

by Keith CowingJune 26, 2024June 26, 2024

Space Life Science - Grok via Astrobiology.com

Astrochemistry, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Imaging & Spectroscopy, Interstellar

Binding Energies of Ethanol and Ethylamine on Interstellar Water Ices: Synergy Between Theory and Experiments

by Keith CowingJune 26, 2024June 26, 2024

From the prebiotic soup to the creation of biodiversity.

Arctic / Antarctic / Alpine, Astrogeology, Biogeochemical Cycles & Geobiology, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Mapping, Geodesy, Cartography, Mars, Water/Hycean Worlds & Oceanography

Marsquakes May Help Reveal Whether Liquid Water Exists Underground On Mars

by Keith CowingJune 26, 2024June 26, 2024