The Planetary Spectrum Generator (PSG) is an online tool for synthesizing planetary spectra
(atmospheres and surfaces) for a broad range of wavelengths (50 nm to 100 mm, UV/Vis/near-IR/IR/far-IR/THz/sub-mm/Radio) from any observatory (e.g., JWST, ALMA, Keck, SOFIA), any orbiter (e.g., MRO, ExoMars, Cassini, New Horizons), or any lander (e.g., MSL).
This is achieved by combining several state-of-the-art radiative transfer models, spectroscopic databases and planetary databases (i.e., climatological and orbital).
The radiative-transfer suite of PSG is applicable to a broad range of planetary objects
in our Solar System (e.g., planets, moons, comets, asteroids, TNOs, KBOs) and beyond (e.g., exoplanets).
The tool was developed and conceptualized in 2015 by Geronimo Villanueva (NASA-GSFC), with the tool first becoming online in 2016.
It has been only possible thanks to decades of meticulous work by hundreds of laboratory spectroscopists (e.g., Quirico and Schmitt 1997; Brown et al. 2013) and radiative transfer modelers (e.g., Edwards 1992; Clough et al. 2005).
Several planetary scientists have offered their help to further improve the capabilities of the tool, and please contact us if you have further suggestions or recommendations.
Emily Wilson (NASA, telluric spectral modeling and MERRA2), Michael Kelley (UMD, cometary dust emissions and Afρ),
Vincent Kofman (NASA, high-energy linelists), Matteo Crismani (NASA, ExoMars modeling),
Saxena Prabal (NASA, disk sub-sampling), Thomas Fauchez (NASA, GCMs and exoplanetary atmospheric templates).
Please refer to these publications when employing these PSG modules:
: Villanueva, G. L., Smith, M. D., Protopapa, S., Faggi, S., Mandell, A. M., Planetary Spectrum Generator: an accurate online radiative transfer suite for atmospheres, comets, small bodies and exoplanets, Journal of Quantitative Spectroscopy and Radiative Transfer, Volume 217, pp. 86-104 (2018).
: Villanueva, G. L., Mumma, M. J., Novak, R. E., Kaufl, H. U., Hartogh, P., Encrenaz, T., Tokunaga, A., Khayat, A., Smith, M. D., Strong water isotopic anomalies in the martian atmosphere: Probing current and ancient reservoirs. Science, Volume 348, Issue 6231, pp. 218-221 (2015).
: Smith, M. D.; Wolff, M. J.; Clancy, R. T.; Kleinböhl, A.; Murchie, S. L., Vertical distribution of dust and water ice aerosols from CRISM limb-geometry observations, JGR Planets, Volume 118, Issue 2, pp. 321-334 (2013).
: Protopapa et al., Pluto's global surface composition through pixel-by-pixel Hapke modeling of New Horizons Ralph/LEISA data, Icarus, Volume 287, p. 218-228 (2017).
: Villanueva, G. L., Mumma, M. J., DiSanti, M. A., Bonev, B. P., Gibb, E. L., Magee-Sauer, K., Blake, G. A., Salyk, C., The molecular composition of Comet C/2007 W1 (Boattini): Evidence of a peculiar outgassing and a rich chemistry. Icarus, Volume 216, Issue 1, p. 227-240 (2011).
: Villanueva, Geronimo L., The High Resolution Spectrometer for SOFIA-GREAT: Instrumentation, Atmospheric Modeling and Observations. PhD Thesis, Albert-Ludwigs-Universitaet zu Freiburg, ISBN 3-936586-34-9, Copernicus GmbH Verlag (2004).
: Villanueva, G. L., Mumma, M. J., Magee-Sauer, K., Ethane in planetary and cometary atmospheres: Transmittance and fluorescence models of the nu7 band at 3.3 μm. Journal of Geophysical Research, Volume 116, Issue E8, CiteID E08012 (2011).
: Villanueva, G. L., Mumma, M. J., Bonev, B. P., Novak, R. E., Barber, R. J., Disanti, M. A., Water in planetary and cometary atmospheres: H2
O/HDO transmittance and fluorescence models. Journal of Quantitative Spectroscopy and Radiative Transfer, Volume 113, Issue 3, p. 202-220. (2012).
: Villanueva, G. L., DiSanti, M. A., Mumma, M. J., Xu, L.-H., A Quantum Band Model of the nu3 Fundamental of Methanol (CH3
OH) and Its Application to Fluorescence Spectra of Comets. The Astrophysical Journal, Volume 747, Issue 1, article id. 37, 11 pp. (2012).
: Villanueva, G. L., Magee-Sauer, K., Mumma, M. J., Modeling of nitrogen compounds in cometary atmospheres: Fluorescence models of ammonia (NH3
), hydrogen cyanide (HCN), hydrogen isocyanide (HNC) and cyanoacetylene (HC3
N). Journal of Quantitative Spectroscopy and Radiative Transfer, Volume 129, p. 158-168. (2013).
Security, Performance and Compliance
The PSG servers and applications are frequently tested to ensure the highest standards of security, performance and online compliance.
These tests are performed employing state of the art industry tools (e.g., google analytics, mozilla observatory) that utilize
comprehensive and stringent methods. See below the latest scores obtained using these applications on the PSG servers.