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Between 1973 December 1 and 1974 February 2, optical emission lines from the gas cloud surrounding comet Kohoutek were observed using a double Fabry-Perot etalon spectrometer at Kitt Peak National Observatory. The spectrometer had a resolving power of 40,000, corresponding to a velocity resolution of about 7.5 km sec-1. With this resolution it was possible to use the cometearth relative velocity to resolve faint cometary Hα λ6563,  λ6300 and other emission lines from geocoronal and airglow emissions and to study the cometary line profiles in order to obtain information about the composition, effective temperatures, outflow velocities, and production rates of atoms and ions in the cometary envelope.
This poster described a method under development that promises to be useful for 3-D spectroscopic studies of extremely faint, spatially extended astronomical sources. The method, which we call Spatial Heterodyne Spectroscopy (SHS), is a relative of the conventional scanning Fourier Transform Spectrometer (FTS), but is free of any scanning elements. We foresee ground-based and space applications for studies of the interstellar medium and the upper atmospheres of solar system objects. Basic configurations that have been tested in the laboratory were described. The SHS instrument we are currently emphasizing for development is intended for a rocket experiment to measure C IV λ1548,51 doublet emission at a resolving power of 20,000 from the hot ISM. Eventually we hope to provide velocity-resolved all-sky maps of selected FUV lines to complement maps obtained at other wavelengths.
Our interests in the general field of astrophysics lie principally in two areas: 1) the study of extremely faint emission lines from the interstellar medium, galactic halo, and intergalactic clouds, and 2) the study of neutral and ionized components of the outer atmospheres of solar system objects, including the earth. These studies require instruments of the highest possible area-solid angle product, but typically do not require extremely high spatial resolution. This paper highlights our past work in these areas, and discusses new instrumental approaches we are developing.
The Wisconsin Plasma Astrophysics Laboratory (WiPAL) is a flexible user facility designed to study a range of astrophysically relevant plasma processes as well as novel geometries that mimic astrophysical systems. A multi-cusp magnetic bucket constructed from strong samarium cobalt permanent magnets now confines a
, fully ionized, magnetic-field-free plasma in a spherical geometry. Plasma parameters of
provide an ideal testbed for a range of astrophysical experiments, including self-exciting dynamos, collisionless magnetic reconnection, jet stability, stellar winds and more. This article describes the capabilities of WiPAL, along with several experiments, in both operating and planning stages, that illustrate the range of possibilities for future users.
An essential aspect of carbon (C) accounting is the development of methods and technologies for measurement and monitoring of C pools and fluxes. Forest and agricultural systems are key to the C cycle, as they hold and rapidly exchange large amounts of C, and human-influenced dynamics of C in these systems are very large. Wetlands, streams, and rivers are important reservoirs and exchange points for C, with C in land and hydrologic systems vulnerable to land-use impacts and other natural disturbance forces. In the context of climate change, the sizes of C pools and magnitudes of C fluxes (see Chapter 2) need to be both well understood for modeling purposes and accurately monitored to quantify and attribute changes driven by land-change processes and confounded by climate-change forces.
Direct-measurement methods for C accounting, such as a ground-based inventories, can be inappropriate for covering large landscapes to document extensive C pools or for repeating measurements needed to adequately account for C dynamics. However, if properly deployed, remote sensing systems can be used to provide the spatially synoptic and temporally frequent coverage needed to document land conditions and changes over time (Cohen and Goward 2004; Houghton and Goetz 2008). Remote sensing tools and techniques have developed since the first airborne sensors (photographic cameras) were deployed in the early 1900s. They have progressed from simple passive recording devices to advanced passive and active sensing systems operating from airborne and spaceborne platforms. Remote sensing science includes the data collection technologies and data analysis techniques developed to use remotely sensed data within the framework of spatial data analyses.
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