A method for the determination of abundance ratios in the outer planets—Application to Jupiter

摘要: Abstract A new method is defined for the determination of abundance ratios in atmospheres outer planets, using visible and near-infrared spectroscopic data. We have selected a set four conditions which determine choice pairs lines (or bands) two different species so that scattering processes are necessarily same both lines. Then, ratio can be measured directly from absorption coefficients these independent involved line formation. It shown large dispersion “apparent abundances” by RLM CH4 NH3 actually distributed as function strength lines, but seems much less dependent upon wavelength. These results then applied to 12C/13C, C/H, D/H, C/N atmosphere Jupiter. The derived values 12C/13C=89−10+12, C/H=6.2±2.1 × 10−4, D/H=1.3±1.0 10−5, C/N=19−7+13. In consequence, there no evidence enrichment deuterium carbon with respect hydrogen Jovian compared expected composition primordial nebula. Moreover, strong value suggests nitrogen trapped condensed compounds below cloud, possibly NH4SH or aqueous ammonia solutions.