OP Lunch Talk #22


Gerónimo Villanueva (NASA Goddard Space Flight Center) talks about “the Planetary Spectrum Generator (PSG): a comprehensive modeling and retrieval tool”.

“The Planetary Spectrum Generator (PSG) is an online radiative-transfer suite (https://psg.gsfc.nasa.gov) applicable to a broad range of planets, comets, asteroids, small-bodies and exoplanets, which is now widely used by the planetary community, with up to 1 million hits/month. PSG can synthesize planetary spectra (atmospheres and surfaces) for a broad range of wavelengths (0.1 μm to 100 mm, UV/Vis/near-IR/IR/far-IR/THz/sub-mm/Radio) from any telescope, observatory, orbiter or rover. This is achieved by combining several state-of-the-art radiative transfer models, spectroscopic databases and planetary climatological models. PSG has three-dimensional orbital calculator for all objects in the solar-system and confirmed exoplanets, while the radiative-transfer models can ingest billions of spectral lines from hundreds of species from several spectroscopic repositories. It integrates the latest radiative-transfer and scattering methods in order to compute high resolution spectra via line-by-line calculations, and utilizes the efficient correlated-k method at moderate resolutions. PSG includes a realistic noise calculator that integrates several telescope / instrument configurations (e.g., interferometry, coronagraphs) and detector technologies (e.g., CCD, heterodyne detectors, bolometers). PSG also includes a robust 3D climate module (GlobES), permitting to compute exoplanetary spectra and phase curves by ingesting a broad range of climatological data. Beyond the computation of spectra, PSG has also an advanced retrieval package implementing two advanced methods: optimal estimation and an efficient nested sampling Bayesian framework. In this presentation, I will present the latest developments and applications of the tool.”

Should we have any questions for the speaker, or anybody within the planetary science community who might be able to answer you, please ask below; or share any useful resources related to the topic.