Spectral comparison and stability of red regions on Jupiter

Abstract

A rare red cyclone visible on Jupiter in 1994 and 1995 falls in a class of vortices that are intensely colored, yet low altitude, unlike the Great Red Spot (GRS). Dynamical modeling indicates that the presence of nearby anticyclones both aids in formation and lead to the destruction of the cyclone. A study of absolute spectral reflectance from Hubble Space Telescope imaging data shows that GRS is not typically the "reddest" region of the planet. Rather, transient red cyclones and the reddest parts of the North Equatorial Belt show less reflectance than the GRS at all wavelengths, with enhanced absorption at wavelengths near 500 nm. Temporal analysis shows that the darkest regions of the North Equatorial Belt and transient red cyclones are relatively constant in color from 1995 to 2014, while the spectral slope and absolute brightness of the GRS core vary over time. Laboratory data of colored materials that yield a good qualitative fit to the GRS spectrum do not match the spectra of other regions, and wavelengths from 400 to 700 nm may be most diagnostic of chromophore identification.

PlanetCam UPV/EHU: A Two-channel Lucky Imaging Camera for Solar System Studies in the Spectral Range 0.38–1.7μm

“…Those wavelengths are extremely interesting to capture images where chromophore agents strongly absorb solar radiation as in Jupiter and Saturn (Simon-Miller et al 2001a, 2001bStrycker et al, 2011;Ordoñez et al, 2015) and Venus (Travis, 1978;Titov et al, 2012). The Vio filter also provides high contrast for detection of cloud features on Mars (Parker et al, 1999;Sanchez-Lavega et al, 2015). The U-Vio-B absorption range allows to characterize a particular type of absorbing aerosols of unknown origin in the giant planets and Venus whose spatial distribution seems to be related to particular dynamical features Hueso et al 2009;Pérez-Hoyos et al, 2009;Sánchez-Lavega et al, 2013).…”

“…The Vio filter covers the spectral range below 410 nm down to the atmospheric and detector cut-off, complementing the classical U (ultraviolet) and B (blue) bands, placed at both wavelength sides. Those wavelengths are extremely interesting to capture images where chromophore agents strongly absorb solar radiation as in Jupiter and Saturn (Simon-Miller et al 2001a, 2001bStrycker et al 2011;Ordonez-Etxebarria et al 2016;Simon et al 2015) and Venus (Travis 1978;Titov et al 2012). The Vio filter also provides high contrast for detection of cloud features on Mars (Parker et al 1999;Sánchez-Lavega et al 2015).…”