Spectroscopy Archives - Page 139 of 150 - Astrobiology

Mass-radius diagram. The green circles show the exoplanet data from exoplanets.eu, the black stars show the Solar System planets and the blue and orange points show the measured values for TOI-1736 b and TOI-2141 b, respectively. Several models from Zeng et al. (2019) are also plotted for comparison. -- astro-ph.EP

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

TOI-1736 and TOI-2141: Two Systems Including Sub-Neptunes Around Solar Analogs Revealed By TESS And SOPHIE

by Keith CowingNovember 15, 2023November 15, 2023

Planetary systems around solar analogs inform us about how planets form and evolve in Solar System-like environments. We report the detection and characterization of two planetary systems around the solar […]

A dual horizontal axis is used to plot both the wavelength average differential entropy (circle ‘◦’ shapes), and the joint differential entropy of the eigencolours (‘x’ shapes), aligning the horizontal axis at the respective values of the original Earth and the least complex synthetic world. The fixed point alignment of the horizontal axes changes the scale of each axis. The vertical axis shows the corresponding wavelength average statistical complexity for both measures. Perforated lines show the distinction between world types. -- astro-ph.EP

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

Planetary Complexity Revealed by the Joint Differential Entropy of Eigencolours

by Keith CowingNovember 14, 2023November 14, 2023

We propose a measure, the joint differential entropy of eigencolours, for determining the spatial complexity of exoplanets using only spatially unresolved light curve data.

12CO+ and 13CO+ theoretical spectra superimposed to the observational data obtained on comet C/2016 R2. The relative intensity of 13CO+ emission lines are based on the 12CO+ fit of the emission lines. They do not respect the intensities observed in this comet, the purpose of this plot being only to show the wavelength shift between the emission lines of these two isotopologues. -- astro-ph.EP

Astrochemistry, Biochemistry & Organic Chemistry, Comets and Asteroids, Imaging & Spectroscopy, Status Report

Comets 12CO+ and 13CO+ Fluorescence Models For Measuring The 12C/13C Isotopic Ratio In CO+

by Keith CowingNovember 13, 2023November 13, 2023

Context: CO is an abundant species in comets, creating CO+ ion with emission lines that can be observed in the optical spectral range. A good modeling of its fluorescence spectrum […]

Outline of the Ariel Challenge dataset generation. The input parameters are used to generate the synthetic exoplanet spectra and noise arrays. A Nested Sampling is carried by the Ariel Data Challenge Organising team on these synthetic ideal spectra, producing samples of the target parameters. Our Machine Learning model aims to reproduce the samples of parameters of the Nested Sampling. See text for more details. -- astro-ph.EP

AI - Data - Apps - Cybernetics, Ariel Mission, Astronomy & Telescopes, Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report

Simulation-based Inference for Exoplanet Atmospheric Retrieval: Insights from winning the Ariel Data Challenge 2023 using Normalizing Flows

by Keith CowingNovember 12, 2023October 16, 2024

Advancements in space telescopes have opened new avenues for gathering vast amounts of data on exoplanet atmosphere spectra. However, accurately extracting chemical and physical properties from these spectra poses significant […]

Chip scale, ultrafast mode-locked laser based on nanophotonic lithium niobate. CREDIT Alireza Marandi

Away Teams & Field Reports, Biosignatures & Paleobiology, Exploration Gear & Tech, Imaging & Spectroscopy, Nanotechnology & SynBio, Press Release, Tricorders & Sensors

Tricorder Tech: High-performance Ultrafast Lasers That Fit On A Fingertip

by Keith CowingNovember 10, 2023November 10, 2023

Editor’s note: as we develop the instruments that Away Teams use on Astrobiology expeditions, compactness and functionality will be of paramount importance. Having exceptionally compact imaging systems such as this […]

This enhanced image of the Jovian moon Ganymede was obtained by the JunoCam imager aboard NASA's Juno spacecraft during the mission's June 7, 2021, flyby of the icy moon on Juno's 34th pass close to Jupiter. This is an extended, upscaled and artistically enhanced version of a previously released JunoCam image: PIA24681. larger image

Biosignatures & Paleobiology, Ganymede, Icy Worlds, Imaging & Spectroscopy, Press Release, Water/Hycean Worlds & Oceanography

Salts and Organics Observed on Ganymede’s Surface

by Keith CowingOctober 30, 2023October 30, 2023

Data collected by NASA’s Juno mission indicates a briny past may be bubbling to the surface on Jupiter’s largest moon.

Mass-radius diagram showing confirmed planets with mass uncertainties < 20% in grey circles, with TOI-544 b shown as the black circle. Left: the coloured tracks show different potential planet compositions from Zeng et al. (2019), assuming a planetary equilibrium temperature of 1000 K. The dashed lines show compositions of an Earth-like rocky core surrounded by a layer of H-He in varying percentages by mass, the solid lines show water world compositions with varying water mass fractions, the dotted lines show rocky and Earth-like rocky compositions. TOI-544 b is closest to the tracks with 100% H2O and 50% H2O with 50% rock. Right: the same as the left panel but the the dashed lines show compositions of an Earth-like rocky core surrounded by a layer of H-He in varying percentages by mass from Lopez & Fortney (2014) using the models for a 10Gyr planet, with solar metalicity and flux of 10F⊕, the solid lines show compositions from Aguichine et al. (2021) of irradiated ocean worlds with varying water mass fractions, and the dotted lines show the same rocky and Earth-like rocky compositions from Zeng et al. (2019). TOI-544 b is closest to models with either 30% water mass fraction, or a rocky core with a Hydrogen envelope of between 0.5 - 1%. The data is downloaded from the NASA Exoplanet Archive. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exploration Gear & Tech, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Status Report, Water/Hycean Worlds & Oceanography

TOI-544 b: A Potential Water-world Inside The Radius Valley In A Two-planet System

by Keith CowingOctober 24, 2023October 24, 2023

We report on the precise radial velocity follow-up of TOI-544 (HD 290498), a bright K star (V=10.8), which hosts a small transiting planet recently discovered by the Transiting Exoplanet Survey […]

Atmospheric and stellar retrieval results for HAT-P-18 b. Top: Retrieved model transmission spectra from our JWST/NIRISS spectra (black errors). For each of the three retrieval codes (Poseidon; purple, SCARLET; orange, and Aurora; blue), the median retrieved spectrum (solid lines) and 1 𝜎 confidence intervals (shaded contours) are shown. The most important model features required to explain HAT-P-18 b’s NIRISS transmission spectrum are annotated. All three codes adopt the one heterogeneity model for this comparison. Bottom: Posterior probability distributions corresponding to the retrieval model in the top panel. The top row shows retrieved atmospheric properties with constrained values, the middle row shows non-detected chemical species with abundance upper limits, and the bottom row shows the retrieved unocculted starspot properties. Each histogram is annotated with the retrieved median and ± 1 𝜎 confidence intervals from the Poseidon retrieval for reference (see Table 4 for the results from all three codes). -- astro-ph.SR

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

Near-Infrared Transmission Spectroscopy of HAT-P-18b with NIRISS: Disentangling Planetary and Stellar Features in the Era of JWST

by Keith CowingOctober 24, 2023October 24, 2023

The JWST Early Release Observations (ERO) included a NIRISS/SOSS (0.6-2.8μm) transit of the ∼850K Saturn-mass exoplanet HAT-P-18b. Initial analysis of these data reported detections of water, escaping helium, and haze.

Continuum emission at 99 GHz in grey scale overlaid by contours of SO J = 23 − 12 at 99.3 GHz (top) and SiO J = 2 − 1 at 86.85 GHz (bottom) integrated intensities. The inner integration limits vary such that channels that contain deep absorption are excluded. The outer integration limits are fixed at 15 and 115 km s−1 for blue- and red-shifted SO emission, respectively, and 5 and 130 km s−1 for blue- and red-shifted SiO emission, respectively (see also Fig. 3). The blue and red contours start at 5σ and then increase by a factor of 2, where σ = 10.5 (SO, blue), 10.8 (SO, red), 4.5 (SiO, blue), and 5.8 K km s−1 (SiO, red) and corresponds to an average noise level that was measured in the respective map. The black contour indicates the 3σ level of the continuum emission (see Fig. 1). Based on the SO maps, we identify collimated features possibly tracing outflow axes that are shown as solid and dashed black arrows and labelled aB1, aR1, and aR2. The markers are the same as in Fig. 1. In addition to N2, the hot core N3 identified by Bonfand et al. (2017) is marked with a cyan tetragon. Blue and pink star markers indicate H2O maser spots (McGrath et al. 2004) with blue- and red-shifted velocities, respectively, with respect to 3sys ≡ 62 km s−1 . The HPBW is shown in the bottom-right corner of each panel. The position offsets are given with respect to the ReMoCA phase centre (black cross). The maps are not corrected for primary beam attenuation. -- astro-ph.GA

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biosignatures & Paleobiology, Imaging & Spectroscopy, Interstellar, Status Report

Shocking Sgr B2(N1) With Its Own Outflow: A New Perspective On Segregation Between O- and N-bearing Molecules

by Keith CowingOctober 21, 2023October 19, 2023

We want to investigate the influence of the powerful outflow driven by the hot core Sgr B2(N1) on the gas molecular inventory of the surrounding medium.

Comparison between the observed data (red) and the model (blue) with Teff , log g , and metallicity of 3200 K, 5.0 dex and −0.5 dex, respectively. The Top panel shows some alpha elements (e.g., Ti I and Mg I) as well as several isolated and blended Fe I lines. The middle panel shows the Na I doublet frequently used in several studies as metallicity indicators of M dwarfs. The bottom panel shows numerous absorption features of the CO band head starting around 2.29 µm (red dashed lines). -- astro-ph.EP

Astronomy & Telescopes, Barnard's Star, Habitable Zones, Imaging & Spectroscopy, Status Report

Comprehensive High-resolution Chemical Spectroscopy of Barnard’s Star with SPIRou

by Keith CowingOctober 19, 2023October 1, 2024

Determination of fundamental parameters of stars impacts all fields of astrophysics, from galaxy evolution to constraining the internal structure of exoplanets.