Transmission spectroscopy Archives - Page 5 of 6 - Astrobiology

The mass-radius diagram for small planets. Data comes from the NASA Exoplanet Archive’s planetary systems table, as accessed on 2022-Nov-17 (NASA Exoplanet Archive 2022). Planets with mass and radius measurements to better than 50% and 15% fractional precision, respectively, are shown as the circles with 1σ error bars. The opacity of the points is proportional to mass measurement precision (i.e., a less precise mass measurement translates to a more transparent marker). Color corresponds to equilibrium temperature assuming zero Bond albedo and full day-night heat redistribution. Underlying contours come from Gaussian kernel density estimation (KDE) of the confirmed planets described above. The 11 transiting planets from this work are overplotted as the stars. Mass upper limits (98% confidence) are plotted for HD 25463 c (yellow star near the radius valley) and HIP 9618 c (labeled). A handful of composition curves are plotted for reference (Lopez & Fortney 2014; Zeng et al. 2016, 2019). The curves of H/He envelopes atop Earth-like cores come from Lopez & Fortney (2014) and are chosen for a planet receiving 10× Earth’s incident flux (i.e., Teq ≈ 500 K) orbiting a 10 Gyr-old, solar-metallicity star. The 50% water plus 50% Earth-like composition curve from Zeng et al. (2019) is calculated for a fixed temperature of 700 K at 100 bar, which determines the planetary model’s specific entropy. Note that familiar features of the planet radius distribution are now visible as two-dimensional features in the mass-radius plane. These include the radius valley (Fulton et al. 2017; Van Eylen et al. 2018), with center near 6 M⊕ and 1.8 R⊕, and the radius cliff (e.g., Kite et al. 2019), as seen by in the steep drop off in the number of planets around 3 R⊕. -- astro-ph.EP

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

The TESS-Keck Survey. XVI. Mass Measurements for 12 Planets in Eight Systems

by Keith CowingJune 29, 2023June 29, 2023

With JWST’s successful deployment and unexpectedly high fuel reserves, measuring the masses of sub-Neptunes transiting bright, nearby stars will soon become the bottleneck for characterizing the atmospheres of small exoplanets […]

Reproduced from Rimmer et al. (2021b). Primary spectral features of a selection of prebiosignature molecules at JWST-probable wavelengths. The icons represent major physical and geochemical sources of the molecules, with primary prebiosignatures being directly associated with prebiotic chemistry. The species included are carbon monoxide (CO), hydrogen sulfide (H2S), sulfur dioxide (SO2), imidazole (C3N2H4), cyanamide (CH2N2), nitric oxide (NO), methane (CH4), acetylene (C2H2), and hydrogen cyanide (HCN). We include all of these except imidazole and cyanamide in our study. We also investigate ammonia and formaldehyde as potential prebiosignatures. Transparency indicates the strength of the features, with weaker features being more transparent. CME = Coronal Mass Ejection. -- astro-ph.EP

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

Prebiosignature Molecules Can Be Detected In Temperate Exoplanet Atmospheres With JWST

by Keith CowingJune 5, 2023June 5, 2023

The search for biosignatures on exoplanets connects the fields of biology and biochemistry to astronomical observation, with the hope that we might detect evidence of active biological processes on worlds […]

Orbital period versus a metric of planet atmosphere inflation with real planets plotted. Lines indicate the boundaries where the offset between transmission spectra with and without rotation reach values of 30 ppm, 60 ppm, and 100 ppm. The change in the transmission spectrum due to rotation is strongest towards the lower right. Where the effect of rotation exceeds the 30 ppm limit, the planets are marked with their names. Cycle 1 JWST targets WASP-19 b and WASP-121 b are also marked and highlighted in orange. -- astro-ph.EP

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

Effect of Centrifugal Force on Transmission Spectroscopy of Exoplanet Atmospheres

by Keith CowingMay 17, 2023May 17, 2023

Transmission spectroscopy is one of the most successful methods of learning about exoplanet atmospheres.

S/N map showing the detection of H2O in the atmosphere of HD 189733 b with a S/N of 5.4, via the order-wise detrending optimisation of the S/N from ΔCCF. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report

Robustness Measures For Molecular Detections Using High-Resolution Transmission Spectroscopy Of Exoplanets

by Keith CowingMarch 3, 2023March 3, 2023

Ground-based high-resolution transmission spectroscopy has emerged as a promising technique for detecting chemicals in transiting exoplanetary atmospheres. Despite chemical inferences in several exoplanets and previous robustness studies, a robust and […]

HighResolution

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

High-Resolution Transmission Spectroscopy of the Terrestrial Exoplanet GJ 486b

by Keith CowingDecember 22, 2022December 22, 2022

Terrestrial exoplanets orbiting M-dwarf stars are promising targets for transmission spectroscopy with existing or near-future instrumentation.

Natalie M. Batalha, Professor of Astronomy & Astrophysics, UC Santa Cruz

Astronomy & Telescopes, Biosignatures & Paleobiology, Habitable Zones, Imaging & Spectroscopy, Press Release, Reports, Roadmaps, & Plans

Congressional Testimony By Natalie Batalha: Early Science Results for Transiting Exoplanets Observed by JWST

by Keith CowingNovember 25, 2022November 25, 2022

JWST is ushering in a new epoch of exoplanet science that will rewrite textbooks. Progress will stem largely from the characterization of exoplanet atmospheres enabled by JWST technology. Herein, I […]

earlyNIRSpec PRISM

Astrogeology, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Press Release

Early Release Science Of The Exoplanet WASP-39b With JWST NIRSpec PRISM

by Keith CowingNovember 21, 2022November 21, 2022

Transmission spectroscopy of exoplanets has revealed signatures of water vapor, aerosols, and alkali metals in a few dozen exoplanet atmospheres.

Early Release Science

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

Early Release Science Of The Exoplanet WASP-39b With JWST NIRISS

by Keith CowingNovember 21, 2022November 21, 2022

Transmission spectroscopy provides insight into the atmospheric properties and consequently the formation history, physics, and chemistry of transiting exoplanets. However, obtaining precise inferences of atmospheric properties from transmission spectra requires […]

Groundbased

Astronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release

Ground-based Optical Transmission Spectroscopy of the Nearby Terrestrial Exoplanet LTT 1445Ab

by Keith CowingOctober 24, 2022October 24, 2022

Nearby M dwarf systems currently offer the most favorable opportunities for spectroscopic investigations of terrestrial exoplanet atmospheres.

IsLTT 1445

Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Press Release

Is LTT 1445 Ab a Hycean World or a cold Haber World? Exploring the Potential of Twinkle to Unveil Its Nature

by Keith CowingSeptember 27, 2022September 27, 2022

We explore the prospects for Twinkle to determine the atmospheric composition of the nearby terrestrial-like planet LTT 1445 Ab, including the possibility of detecting the potential biosignature ammonia (NH3).