Cool, Cloudy Nights on an Ultrahot Neptune: A Panchromatic NIRISS/NIRSpec Transmission Spectrum of LTT 9779 b

arXiv:2609.36206 · astro-ph.EP · Submitted 2026-09-28 · Read on arXiv

astro-ph.EP

Submitted: 2026-09-28

Updated: 2026-09-28

Code: https://github.com/castro-gzlz/nep-des

Project page: https://lkreidberg.github.io/batman/docs/html/index.html

Terminology

• Metallicity — 52× in this paper · explained in 3 episodes
• Abundance — 28× in this paper · explained in 1 episode
• Trace — 8× in this paper · explained in 2 episodes
• Transmission spectroscopy — 7× in this paper · explained in 2 episodes
• Degeneracy — 5× in this paper · explained in 3 episodes
• Aperture — 4× in this paper · explained in 1 episode
• Calibration — 4× in this paper · explained in 7 episodes
• Forward modeling — 4× in this paper · explained in 2 episodes
• Consistency — 2× in this paper · explained in 3 episodes
• James Webb Space Telescope — 2× in this paper
• European Space Agency — 1× in this paper
• Robustness — 1× in this paper · explained in 5 episodes
• Verification — 1× in this paper · explained in 2 episodes

Sources

• JWST-SUPER I: New insights into irradiated warm Neptunes atmospheres from MIRI observations of HD 106315 c

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