Geronimo L. Villanueva (born April 9, 1978) is a planetary astronomer at NASA Goddard Space Flight Center.

[7][8][9][10] His work on high-resolution molecular spectroscopy of planetary and cometary atmospheres led the International Astronomical Union to name minor planet 9724 after Villanueva,[11] while the American Astronomical Society awarded him the Urey Prize (young planetary scientist of the year) in 2015.

Villanueva is a planetary scientist who specializes in spectroscopic studies of planets, comets and small icy bodies.

[2][3] Villanueva also obtained the first astronomical measurement of water D/H of a periodic comet,[6] conducted a deep search for organics in the Martian atmosphere[7][8][9][10] and discovered multiple isotopic carbon dioxide bands on Mars at infrared wavelengths.

He develops non-LTE radiative transfer models and quantum molecular models at GSFC resulting in billions of spectral lines suitable for cometary, planetary and astrophysical sciences, including the study of exoplanets.