2.7- to 4.1-μm spectrophotometry of icy satellites of Saturn and Jupiter

We present spectrophotometry in the 27–41 μm spectral region for icy satellites of Saturn (Tethys, Dione, Rhea, Iapetus, and Hyperion) and Jupiter (Europa, Ganymede, and Callisto). The 3.6-μm reflectance peak characteristic of fine-grained water ice is observed prominently on the satellites of Saturn, faintly on the leading side of Europa, and not all on Ganymede, Callisto, or the dark side of Iapetus. The spectral reflectances of these icy satellites may be affected by their equilibrium surface temperatures and magnetospheric effects.     

The Balderton Sand and Gravel: Pre-Ipswichian cold stage fluvial deposits near Lincoln,England

The Balderton Terrace marks a former course of the River Trent between Newark and the Lincoln Gap. The principal deposit, the Balderton Sand and Gravel, is interpreted as a braided river sediment. Ice wedge casts truncated by intraformational erosion surfaces at many levels indicate syndepositional permafrost. Remnant cover deposits overlying the Balderton Sand and Gravel include the partly aeolian Whisby Sand. Locally, both the upper part of the Balderton Sand and Gravel and the cover deposits exhibit features indicative of temperate climate pedogenesis. All these deposits are affected by subsequent cryoturbation. On the basis of these features and the geomorphological and topographical relationship to other terrace deposits of the area, the Balderton Sand and Gravel and Whisby Sand are regarded as post-Hoxnian and pre-lpswichian, i.e. Wolstonian. Electron spin resonance age determinations for fossil elephant teeth and amino acid analyses on molluscs from the Balderton Sand and Gravel suggest correlation with Oxygen Isotope Stage 6. The Balderton Sand and Gravel has yielded a cold-climate mammalian fauna dominated by woolly mammoth and woolly rhinoceros, though rarer species suggest periods of milder climate. Silts from channels near the base of the deposit have produced pollen, mollusc, ostracod and beetle assemblages also indicating a cold climate.     

Neutral gas composition measurements between 80 and 120 km

Atmospheric composition in the turbopause regime was determined by four rocket-borne mass spectrometers, which employed shock-freezing cryo-ion sources. Number densities of N₂, O₂, O, Ar and CO₂ are presented for these experiments. The results are compared with those of other rocket experiments taken from the literature. Ar/N₂ ratios are analyzed with respect to atmospheric turbulence. Magnitude and variability of atomic oxygen layer maximum density and layer content are discussed. Variations of O densities and simultaneous Ar/N₂ ratio changes are compared. Six CO₂ measurements are discussed in terms of CO₂/N₂ ratios.     

An ion-exchange technique for concentrating ammonia from small volumes of seawater

An ion-exchange technique was used to concentrate ammonia from seawater. Precipitation of bivalent cations, prior to concentration, reduced the variability of ammonia recovery from the ion-exchange column and lengthened column life. Analysis of the eluate was by the phenolhypochlorite reaction. The method was designed for use with small seawater samples (>10ml) and has the advantage that it can be adapted for use with small volumes of seawater with no loss in sensitivity. In a 10 ml seawater example NH₃-N concentrations of 10–150 μg l^?1 were accurately determined.     

On the Principle of Least Interaction Action and the Laplacean satellites of Jupiter and Uranus

The Principle of Least Interaction Action, which explains the observed preference in the Solar System for two-satellite resonant configurations, is shown to apply also to the Laplacean satellites of Jupiter and Uranus, in the sense that these triplet resonant structures lie close to configurations for which the time-mean of the action associated with the mutual interaction of the satellites is an overall minimum. Far from the minimum configuration, significant changes take place in the major semi-axes on time-scales ～10⁶-10⁷y. Both systems require times ～10⁸ y to come close to the minimum configuration; to approach resonance to the observed precision of the Laplace relationship (3×10^?4 for the Uranian case, 2×10^?7 for the Jovian case) requires, for both systems, a time closely comparable with the age of the solar system.