CRISM (Compact Reconnaissance Imaging Spectrometer for Mars) is a hyperspectral imager that will be launched on the MRO (Mars Reconnaissance Orbiter) spacecraft in August 2005. MRO's objectives are to recover climate science originally to have been conducted on the Mars Climate Orbiter (MCO), to identify and characterize sites of possible aqueous activity to which future landed missions may be sent, and to characterize the composition, geology, and stratigraphy of Martian surface deposits. MRO will operate from a sun-synchronous, near-circular (255x320 km altitude), near-polar orbit with a mean local solar time of 3 PM.CRISM's spectral range spans the ultraviolet (UV) to the mid-wave infrared (MWIR), 383 nm to 3960 nm. The instrument utilizes a Ritchey-Chretien telescope with a 2.12° field-of-view (FOV) to focus light on the entrance slit of a dual spectrometer. Within the spectrometer, light is split by a dichroic into VNIR (visible-near-infrared, 383-1071 nm) and IR (infrared, 988-3960 nm) beams. Each beam is directed into a separate modified Offner spectrometer that focuses a spectrally dispersed image of the slit onto a two dimensional focal plane (FP). The IR FP is a 640 x 480 HgCdTe area array; the VNIR FP is a 640 x 480 silicon photodiode area array. The spectral image is contiguously sampled with a 6.6 nm spectral spacing and an instantaneous field of view of 61.5 µradians. The Optical Sensor Unit (OSU) can be gimbaled to take out along-track smear, allowing long integration times that afford high signal-to-noise ratio (SNR) at high spectral and spatial resolution. The scan motor and encoder are controlled by a separately housed Gimbal Motor Electronics (GME) unit. A Data Processing Unit (DPU) provides power, command and control, and data editing and compression.CRISM acquires three major types of observations of the Martian surface and atmosphere. In Multispectral Mapping Mode, with the gimbal pointed a planet nadir, data are collected at frame rates of 15 or 30 Hz. A commandable subset of wavelengths is saved by the DPU and binned 5:1 or 10:1 cross-track. The combination of frame rates and binning yields pixel footprints of 100 or 200 m. In this mode, nearly the entire planet can be mapped at wavelengths of key mineralogic absorption bands to select regions of interest. In Targeted Mode, the gimbal is scanned over ±60°f rom nadir to remove most along-track motion, and a region of interest is mapped at full spatial and spectral resolution. Ten additional abbreviated, pixel-binned observations are taken before and after the main hyperspectral image at longer atmospheric path lengths, providing an emission phase function (EPF) of the site for atmospheric study and correction of surface spectra for atmospheric effects. In Atmospheric Mode, the central observation is eliminated and only the EPF is acquired. Global grids of the resulting lower data volume observation are taken repeatedly throughout the Martian year to measure seasonal variations in atmospheric properties.

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A traveling compression region (TCR) is a several‐minute long compression of the lobe magnetic field produced by a plasmoid as it moves down the tail. They are generally followed by a longer interval of southward tilting magnetic fields. This study reports the first comprehensive survey of TCRs in the distant magnetotail. A total of 116 TCRs were identified in the ISEE 3 magnetic field observations. Of this population, 37 TCRs were observed to be separated by 30 min or more from any other TCR and are termed “isolated” events. “Paired” events are defined as two TCRs separated by less than 30 min. There were 36 such TCRs corresponding to 18 paired events. “Multiple” events were also observed in which more than two TCRs occurred in a series without a gap between TCRs of more than 30 min. The 11 multiple events identified in this study had an average of about four traveling compression regions each for a total of 43 TCRs. The mean amplitude, ΔB/B, and duration, ΔT, for all TCRs were found to be 7.6% and 158 s, respectively. TCRs occurring as isolated events were the largest (ΔB/B = 8.8% and ΔT = 218 s) and those associated with multiple events were the smallest (ΔB/B = 5.6% and ΔT = 84 s). The mean duration of the period of southward tilting Bz following isolated TCRs was 12.3 min. This time interval was found to be quite similar to the average spacing between TCRs in paired and multiple events, 11.2 and 10.2 min, respectively. TCR amplitude and duration were found to be independent of location within the tail lobes suggesting that the plasmoids which cause the TCRs maintain approximately constant volume and shape as they move down the tail. Mean plasmoid dimensions estimated from TCR duration and amplitude under the assumption of a quasi‐rigid magnetopause are 35 RE (length) × 15 RE (width) × 15 RE (height). Utilizing auroral kilometric radiation, the AL index, Pi 2 pulsations at two ground stations, and energetic particle data from three geosynchronous spacecraft, it is found that over 91% of the TCR events identified in this study followed substorm onsets or intensifications. The number of TCR events identified in this study are consistent with their release in association with a new substorm onset every 4‐6 hrs. The results of this study strongly suggest that the release of plasmoids down the tail near the time of expansion phase onset is an integral step in the substorm process and an important element in the substorm energy budget.

A method is presented which allows estimation of the variation of the rate of magnetic reconnection at the day side magnetopause. This is achieved using observations of the cusp particle precipitation made by low‐altitude polar‐orbiting spacecraft. In this paper we apply the technique to a previously published example of a cusp intersection by the DMSP F7 satellite. It is shown that the cusp signature in this case was produced by three separate bursts of reconnection which were of the order of 10 min apart, each lasting roughly 1 min. This is similar to the variation of reconnection rate which is required to explain typical flux transfer event signatures at the magnetopause.

Copper powder was sprayed by the cold-gas dynamic method. In-flight particle velocities were measured with a laser-two-focus system as a function of process parameters such as gas temperature, gas pressure, and powder feed rate. Particle velocities were uniform in a relatively large volume within the plume and agreed with theoretical predictions. The presence of the substrate was found to have no significant effect on particle velocities. Cold-spray deposition efficiencies were measured on aluminum substrates as a function of particle velocity and incident angle of the plume. Deposition efficiencies of up to 95% were achieved. The critical velocity for deposition was determined to be about 640 meters per second.