JWST Archives - Page 35 of 93 - Astrobiology

The ≈1000 au environment of RW Aur at different wavelengths, as observed by ALMA and JWST. Panel (a): compact dust continuum emission at 1.3 mm wavelength (see Kurtovic et al. 2024, for a detailed study). Panel (b): continuum emission from MIRI-MRS subband 1A. Panel (c): Peak emission map of H2S(3). Panel (d): Peak emission map of [Fe II]. Panel (e): Moment 0 map of the 12CO emission at 230.538 GHz, as observed with ALMA. Panel (f): Peak emission map of H2S(3). -- astro-ph.EP

Astrochemistry, Astrogeology, Astronomy & Telescopes, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report

MINDS. Young Binary Systems With JWST/MIRI: Variable Water-rich Primaries And Extended Emission

by Keith CowingAugust 14, 2025August 14, 2025

As part of the JWST GTO program MINDS, we analyze the mid-infrared emission of three Class II binary systems: VW Cha, WX Cha, and RW Aur, to investigate the impact […]

This artist’s concept depicts planet TRAPPIST-1 d passing in front of its turbulent star, with other members of the closely packed system shown in the background. Credit: NASA, ESA, CSA, J. Olmsted (STScI)

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release, TRAPPIST-1

Webb Narrows Atmospheric Possibilities For Earth-sized Exoplanet TRAPPIST-1 d

by Keith CowingAugust 13, 2025August 13, 2025

The exoplanet TRAPPIST-1 d intrigues astronomers looking for possibly habitable worlds beyond our solar system because it is similar in size to Earth, rocky, and resides in an area around […]

The final F444W image produced via classical RDI optimized for extended source emission retrieval (FULL and Subarray combined), shown at a larger field of view to include the outer ring in the left hand panel and zoomed in to the inner regions in the right panel. While the outer ring is not detected in our observations, the inner regions exhibit a marginal (1 σ), low level of asymmetric extended emission. The background sources are “doubled” where the FULL images overlap that were taken 6 months apart). -- astro-ph.EP

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

Searching For Planets Orbiting Epsilon Eridani With JWST/NIRCam

by Keith CowingAugust 13, 2025August 13, 2025

We present observations of ϵ Eridani with the JWST/NIRCam coronagraph aimed at imaging planets orbiting within this system.

Joint posterior constraints on the surface partial pressure of key atmospheric absorbers for atmospheric scenarios similar to solar system terrestrials, with N2 as the background gas. The color shadings correspond to the posterior probability mass, and the contours highlight the 68% and 95% confidence regions from the joint retrieval in each case. The absorber in the N2-background atmosphere is labeled in the top right corner of each panel. The dashed-dotted, dashed, and solid sienna lines correspond to an atmospheric surface pressure of 0.1, 1, and 10 bar. We illustrate where typical models of Archean Earth (AE), Modern Earth (ME), and compositions for Titan (T), early Mars (eMa), Mars (Ma), and Venus (V; Encrenaz & Coustenis 2018) approximately lie relative to our constraints for TRAPPIST-1 d. Star markers correspond to specific cloudy cases, where the planet is modeled as either cloudy or cloud-free (for Titan, Modern Earth, and Venus). For the N2-H2O case, we show as a black dotted line the limit of pressures that would be cut off by refraction in a 11 bar atmosphere (10 bar H2O+1 bar N2). For thinner atmospheres, the impact of refraction on atmosphere detectability is even weaker. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, TRAPPIST-1

Strict Limits On Potential Secondary Atmospheres On The Temperate Rocky Exo-Earth TRAPPIST-1 d

by Keith CowingAugust 13, 2025August 13, 2025

The nearby TRAPPIST-1 system, with its seven small rocky planets orbiting a late-type M8 star, offers an unprecedented opportunity to search for secondary atmospheres on temperate terrestrial worlds.

Octasulfur crown -- Wikipedia

Astrochemistry, Astrogeology, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Imaging & Spectroscopy, Interstellar, Press Release

Chemists Help Solve The Mystery Of Missing Space Sulfur

by Keith CowingAugust 12, 2025August 12, 2025

For decades, astrochemists have been looking for sulfur atoms in space and finding surprisingly little of the element that is a key ingredient to life. A new study could point […]

Suppression index Ξ as a function of mantle thermal gradient ∆T and bulk modulus K. Regions with Ξ > 1.1 (light-shaded) correspond to > 10% enhancements in escape velocity, indicating strong thermoelastic suppression of atmospheric loss. -- astro-ph.EP

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Status Report

Thermoelastic Contraction As A Suppressor Of Atmospheric Escape In Close-in Exoplanets

by Keith CowingAugust 12, 2025

The long-term retention of substantial atmospheres in close-in exoplanets presents a major challenge to classical hydrodynamic escape theory, which predicts rapid mass loss under intense stellar irradiation.

NIRISS/SOSS and NIRSpec/G395H transit spectrum of K2-18b. The spectrum matches that published by M23 after applying a -50 ppm offset to their spectrum. -- astro-ph.EP

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

K2-18b Does Not Meet The Standards Of Evidence For Life

by Keith CowingAugust 11, 2025August 11, 2025

K2-18b, a temperate sub-Neptune, has garnered significant attention due to claims of possible biosignatures in its atmosphere. Low-confidence detections of dimethyl sulfide (DMS) and/or dimethyl disulfide (DMDS) have sparked considerable […]

Exoplanet atmosphere -- NASA larger image

Atmospheres, Climate, Weather, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Origin & Evolution of Life, Status Report, Water/Hycean Worlds & Oceanography

The Diversity Of Exoplanetary Environments And The Search For Signs Of Life Beyond Earth

by Keith CowingAugust 8, 2025

Thousands of exoplanets orbit nearby stars, showcasing a remarkable diversity in mass, size and orbits.

Stellar flares observed in JWST/NIRISS time-series spectroscopy of TRAPPIST-1. Each column shows one flare event during transits of the TRAPPIST-1c or TRAPPIST-1f planets. Tow row: Light curves with the total flux (integrated over the full spectral range and normalized to the mean out-of-transit flux). Colored points indicate pre-flare (green), flare (orange), maximum flare light (red), and post-flare (blue) phases. Green and blue dashed lines mark the average pre- and post-flare flux levels. Middle row: Light curves of the normalized Hα flux. Bottom row: Time-resolved spectrograms (wavelength vs. time) normalized to the pre-flare spectrum. The shaded blue region shows the drop in flux caused by the planetary transit. For comparison, the time axis in all panels are aligned such that t = 0 corresponds to the beginning of the maximum flare light phase. In all four events, the total flux in the post-flare phase is systematically elevated relative to the pre-flare level. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Magnetic Fields, Electromagnetism, bioelectricity,, Press Release, Radiation, Space Weather & Heliophysics, TRAPPIST-1

Flares On TRAPPIST-1 Reveal The Spectrum Of Magnetic Features On Its Surface

by Keith CowingAugust 8, 2025August 8, 2025

TRAPPIST-1 is an M8 dwarf hosting seven known exoplanets and is currently one of the most frequently observed targets of the James Webb Space Telescope (JWST).

χ2 maps for HCN, CO2 + 13CO2, C6H6, C2H4, C2H6, CH4, and water. The color scale shows the χ2min/χ22 . The best fit model (χ2 min/χ2 = 1) is marked with a red circle. A red contour denotes the emitting region radius as listed in Table 2. Gray contours show the emitting radii in au while white contours represent the 1σ, 2σ, and 3σ levels. -- astro-ph.SR

Astrochemistry, Astronomy & Telescopes, Atmospheres, Climate, Weather, Brown Dwarfs, Gas Giants, Imaging & Spectroscopy, Status Report

MINDS. Cha Ha 1, A Brown Dwarf With A hydrocarbon-rich Disk

by Keith CowingAugust 8, 2025August 8, 2025

Context. Recent JWST observations have shown that brown dwarfs (BD) are chemically rich, offering valuable insights into giant planet formation.