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Multicomponent acquisition systems today record incomplete data because they do not measure rotations. Geophones or accelerometers provide linear motion and hydrophones provide pressure, but no current commercial acquisition system includes sensors that measure rotations. Without rotations, the data provide incomplete recording of the wavefield because in three dimensions, there are six degrees of freedom -three linear displacements and three rotations. In two small 2D seismic surveys recorded with six components, three-component geophones were deployed and three-component rotation sensors that measured pitch, roll, and yaw were deployed. Pitch was measured independently with closely spaced geophones. Measuring rotations with closely spaced geophones is not practical in production, but it can be used in research and development to validate rotationsensor data. A comparison of pitch measured by two independent methods finds that they fit after instrument designature. Data provided by rotation sensors have additional value because they can be used in analysis of singular value decomposition (SVD) to identify and separate ground roll and body waves.

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New far ultraviolet spectra of Jupiter with a significant improvement in sensitivity and spectral resolution have been obtained from a sounding rocket by using a 10-channel spectrometer behind a pointing telescope. The major results obtained from these spectra are (1) a new measurement of the Jovian H I X 1216-• brightness (a comparison with other measurements indicates that the Ly a emission is likely to be variable), (2) the measurement of the wavelength-depe_ndent albedo for Rayleigh scattered solar radiation from •1550 to 1875/[ with •25-/[ resolution making it possible to set new upper limits on the abundances of some of the minor,constituents in the upper Jovian atmosphere, and (3) a demonstration that weak emissions between •1250 and •1500 • and near 1600 • are probably the Lyreart bands of H•. excited by low-energy electrons. niques and the observed spectra are presented in section 3. Ifi section 4, spectral features are identified and discussed. EXPERIMENTAL DETAILS

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When lidar pulses travel through a short path that includes a relatively high concentration of aerosols, scattering phenomena can alter the power and temporal properties of the pulses significantly, causing undesirable effects in the received pulse. In many applications the design of the lidar transmitter and receiver must consider adverse environmental aerosol conditions to ensure the desired performance. We present an analytical model of lidar system operation when the optical path includes aerosols for use in support of instrument design, simulations, and system evaluation. The model considers an optical path terminated with a solid object, although it can also be applied, with minor modifications, to cases where the expected backscatter occurs from nonsolid objects. The optical path aerosols are characterized by their attenuation and backscatter coefficients derived by the Mie theory from the concentration and particle size distribution of the aerosol. Other inputs include the lidar system parameters and instrument response function, and the model output is the time-resolved received pulse. The model is demonstrated and experimentally validated with military fog oil smoke for short ranges (several meters). The results are obtained with a lidar system operating at a wavelength of 0.905 microm within and outside the aerosol. The model goodness of fit is evaluated using the statistical coefficient of determination whose value ranged from 0.88 to 0.99 in this study.

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