Simultaneous retrieval of orbital phase resolved JWST/MIRI emission spectra of the hot Jupiter WASP-43b: Evidence of water, ammonia and carbon monoxide

Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) (2024) stae1427

Authors:

Jingxuan Yang, Mark Hammond, Anjali AA Piette, Jasmina Blecic, Taylor J Bell, Patrick GJ Irwin, Vivien Parmentier, Shang-Min Tsai, Joanna K Barstow, Nicolas Crouzet, Laura Kreidberg, João M Mendonça, Jake Taylor, Robin Baeyens, Kazumasa Ohno, Lucas Teinturier, Matthew C Nixon

Observations of Titan’s Stratosphere during Northern Summer: Temperatures, CH3CN and CH3D Abundances

The Planetary Science Journal American Astronomical Society 5:5 (2024) 125-125

Authors:

Alexander E Thelen, Conor A Nixon, Martin A Cordiner, Emmanuel Lellouch, Sandrine Vinatier, Nicholas A Teanby, Bryan Butler, Steven B Charnley, Richard G Cosentino, Katherine de Kleer, Patrick GJ Irwin, Mark A Gurwell, Zbigniew Kisiel, Raphael Moreno

Abstract:

<jats:title>Abstract</jats:title> <jats:p>Titan’s atmospheric composition and dynamical state have previously been studied over numerous epochs by both ground- and space-based facilities. However, stratospheric measurements remain sparse during Titan’s northern summer and fall. The lack of seasonal symmetry in observations of Titan’s temperature field and chemical abundances raises questions about the nature of the middle atmosphere’s meridional circulation and evolution over Titan’s 29 yr seasonal cycle that can only be answered through long-term monitoring campaigns. Here, we present maps of Titan’s stratospheric temperature, acetonitrile (or methyl cyanide; CH<jats:sub>3</jats:sub>CN) abundance, and monodeuterated methane (CH<jats:sub>3</jats:sub>D) abundance following Titan’s northern summer solstice obtained with Band 9 (∼0.43 mm) Atacama Large Millimeter/submillimeter Array observations. We find that increasing temperatures toward high southern latitudes, currently in winter, resemble those observed during Titan’s northern winter by the Cassini mission. Acetonitrile abundances have changed significantly since previous (sub)millimeter observations, and we find that the species is now highly concentrated at high southern latitudes. The stratospheric CH<jats:sub>3</jats:sub>D content is found to range between 4 and 8 ppm in these observations, and we infer the CH<jats:sub>4</jats:sub> abundance to vary between ∼0.9% and 1.6% through conversion with previously measured D/H values. A global value of CH<jats:sub>4</jats:sub> = 1.15% was retrieved, lending further evidence to the temporal and spatial variability of Titan’s stratospheric methane when compared with previous measurements. Additional observations are required to determine the cause and magnitude of stratospheric enhancements in methane during these poorly understood seasons on Titan.</jats:p>

Exploring the directly imaged HD 1160 system through spectroscopic characterisation and high-cadence variability monitoring

Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) (2024) stae1315

Authors:

Ben J Sutlieff, Jayne L Birkby, Jordan M Stone, Annelotte Derkink, Frank Backs, David S Doelman, Matthew A Kenworthy, Alexander J Bohn, Steve Ertel, Frans Snik, Charles E Woodward, Ilya Ilyin, Andrew J Skemer, Jarron M Leisenring, Klaus G Strassmeier, Ji Wang, David Charbonneau, Beth A Biller

Into the red: An M-band study of the chemistry and rotation of β Pictoris b at high spectral resolution

Monthly Notices of the Royal Astronomical Society Oxford University Press (OUP) (2024) stae1277

Authors:

Luke T Parker, Jayne L Birkby, Rico Landman, Joost P Wardenier, Mitchell E Young, Sophia R Vaughan, Lennart van Sluijs, Matteo Brogi, Vivien Parmentier, Michael R Line

Does ‘net zero’ mean zero cows?

Bulletin of the Atomic Scientists Taylor & Francis 80:3 (2024) 153-157

Authors:

John Lynch, Raymond Pierrehumbert