Charge‐coupled device spectral images of spatially resolved regions of Jupiter in the 6190‐ and 8900‐Å methane and 6450‐Å ammonia bands during the 1989 Opposition

Abstract

High‐quality charge‐coupled device spectroscopic observations at different regions of Jupiter in the spectral regions λλ 6000–6600 and 8700–9200 Å at a resolution of 1.2 Å have been obtained. These spectra allowed us to obtain the center‐to‐limb curves of the equivalent widths of the CH4 6190‐Å band, the NH3 6450‐Å band, and the band depth of the 8900‐Å band, as well as their latitudinal distribution. Some asymmetries in the center‐to‐limb distribution of the equivalent widths of the CH4 6190‐Å and NH3 6450‐Å bands were detected, as well as a very prominent decrease toward the planetary limbs for the ammonia band. The latitudinal variations of the CH4 6190‐Å and NH3 6450‐Å equivalent widths were strongly correlated for fractional radii less than 0.4, with a maximum of absorption at the North Equatorial Belt. The South Equatorial Belt, undetectable at visible and near‐infrared continuum wavelengths, was discernable at λ = 8900 Å. Model computations for the Equatorial Region assuming three aerosol layer models gave some constraints on tropospheric atmospheric parameters during the 1989 Jupiter opposition date.