Exoplanets hosting M dwarfs are the best targets to characterize Earth-like or super-Earth planetary atmospheres with the James Webb Space Telescope (JWST). We determine detailed stellar parameters ( Teff, log g, and ξ) and individual abundances of twelve elements for four cool M dwarfs hosting exoplanets TOI-1685, GJ 436, GJ 3470, and TOI-2445, scheduled for future observations by the JWST. The analysis utilizes high-resolution near-infrared spectra from the SDSS-IV APOGEE survey between 1.51-1.69 µm. Based on 1D-LTE plane-parallel models, we find that TOI-2445 is slightly metal-po or ([Fe/H1 =-0.16 ±0.09), while TOI-1685, GJ 436 and GJ 3470 are more metal-rich ([Fe/H1 = 0.06 ±0.18, 0.10 ±0.20 dex, 0.25 ±0.15). The derived C/O ratios for TOI-2445, TOI-1685, GJ 436, and GJ 3470 are 0.526 ±0.027, 0.558 ±0.097, 0.561 ±0.029, and 0.638 ±0.015, respectively. From results for 28 M dwarfs analyzed homogeneously from APOGEE spectra, we find exoplanet-hosting M dwarfs exhibit a C/O abundance ratio approximately 0.01 to 0.05 higher than those with non-detected exoplanets, at limits of a statistically significant offset. A linear regression of [Fe/H1 vs. C/O distribution reveals a noticeable difference in the angular coefficient between FGK dwarfs (0.27) and M dwarfs (0.13). Assuming our abundance ratios of Ca/Mg, Si/Mg, Al/Mg, and Fe/Mg, we determine a mass of 3.276−0.419 +0.448 M⊕ for TOI-2445 b, having density (6.793−0.099 +0.005 g.cm − 3 ) and core mass fraction (0.329−0.049 +0.028 ) very similar to Earth’s. We also present an atlas of 113 well-defined spectral lines to analyze M dwarfs in the Hband and a comprehensive evaluation of uncertainties from variations in the atmospheric parameters, signal-to-noise, and pseudo-continuum.

HZ610x Genomics HZ810x Genomics HZ910x Genomics Crop_R1Illumina RiboZero TruSeq Crop_R2Illumina RiboZero TruSeq Crop_R3Illumina RiboZero TruSeq SG_R1Illumina PolyA TruSeq SG_R2Illumina PolyA TruSeq SG_R3Illumina PolyA TruSeq PV_GF_R1Illumina RiboZero TruSeq PV_GF_R2Illumina RiboZero TruSeq PV_GF_R3Illumina RiboZero TruSeq PV_GF_R4Illumina RiboZero TruSeq PV_GF_R5Illumina RiboZero TruSeq PV_LpWF_R1Illumina RiboZero TruSeq PV_LpWF_R2Illumina RiboZero TruSeq PV_LpWF_R3Illumina RiboZero TruSeq PV_LpWF_R4Illumina RiboZero TruSeq PV_LpWF_R5Illumina RiboZero TruSeq Adult Drosophila foregut contains a diverse set of tissue and cell types. We applied single cell RnA sequencing (scRnA-seq) and bulk RnA sequencing (bulk RnA-seq) to delineate the cellular composition and molecular profile of the foregut and its associated physiological functions.

The photosynthetic amoeba, Paulinella provides a recent (ca. 120 Mya) example of primary plastid endosymbiosis. Given the extensive data demonstrating host lineage-driven endosymbiont integration, we analysed nuclear genome and transcriptome data to investigate mechanisms that may have evolved in Paulinella micropora KR01 (hereinafter, KR01) to maintain photosynthetic function in the novel organelle, the chromatophore. The chromatophore is of alpha-cyanobacterial provenance and has undergone massive gene loss due to Muller's ratchet, but still retains genes that encode the ancestral alpha-carboxysome and the shell carbonic anhydrase, two critical components of the biophysical CO2 concentrating mechanism (CCM) in cyanobacteria. We identified KR01 nuclear genes potentially involved in the CCM that arose via duplication and divergence and are upregulated in response to high light and downregulated under elevated CO2. We speculate that these genes may comprise a novel CO2 delivery system (i.e., a biochemical CCM) to promote the turnover of the RuBisCO carboxylation reaction and counteract photorespiration. We posit that KR01 has an inefficient photorespiratory system that cannot fully recycle the C-2 product of RuBisCO oxygenation back to the Calvin-Benson cycle. Nonetheless, both these systems appear to be sufficient to allow Paulinella to persist in environments dominated by faster-growing phototrophs.

The signal from a transiting planet can be diluted by astrophysical contamination. In the case of circumstellar debris disks, this contamination could start in the mid-infrared and vary as a function of wavelength, which would then change the observed transmission spectrum for any planet in the system. The MIRI/Low Resolution Spectrometer WASP-39b transmission spectrum shows an unexplained dip starting at similar to 10 mu m that could be caused by astrophysical contamination. The spectral energy distribution displays excess flux at similar levels to that which are needed to create the dip in the transmission spectrum. In this Letter, we show that this dip is consistent with the presence of a bright circumstellar debris disk, at a distance of >2 au. We discuss how a circumstellar debris disk like that could affect the atmosphere of WASP-39b. We also show that even faint debris disks can be a source of contamination in MIRI exoplanet spectra.

Context. Long-period transiting exoplanets bridge the gap between the bulk of transit- and Doppler-based exoplanet discoveries, providing key insights into the formation and evolution of planetary systems. The wider separation between these planets and their host stars results in the exoplanets typically experiencing less radiation from their host stars; hence, they should maintain more of their original atmospheres, which can be probed during transit via transmission spectroscopy. Although the known population of long-period transiting exoplanets is relatively sparse, surveys performed by the Transiting Exoplanet Survey Satellite (TESS) and the Next Generation Transit Survey (NGTS) are now discovering new exoplanets to fill in this crucial region of the exoplanetary parameter space.

The kinematics of the stellar halo hold important clues to the assembly history and mass distribution of the Galaxy. In this study, we map the kinematics of stars across the Galactic halo with the H3 Survey. We find a complex distribution that breaks both azimuthal symmetry about the Z -axis and mirror symmetry about the Galactic plane. This asymmetry manifests as large variations in the radial velocity dispersion Gr r from as “cold” as 70 km s − 1 to as “hot” as 160 km s − 1 . We use stellar chemistry to distinguish accreted stars from in-situ stars in the halo, and find that the accreted population has higher σr and radially biased orbits, while the in-situ population has lower Gr r and isotropic orbits. As a result, the Galactic halo kinematics are highly heterogeneous and poorly approximated as being spherical or axisymmetric. We measure radial profiles of σr and the anisotropy parameter [3 over Galactocentric radii 10 −80 kpc, and find that discrepancies in the literature are due to the nonspherical geometry and heterogeneous nature of the halo. Investigating the effect of strongly asymmetric σr and [3 on equilibrium models is a path forward to accurately constraining the Galactic gravitational field, including its total mass.