Space processing applications payload equipment study. Volume 1: Executive summary

A study was conducted to derive and collect payload information on the anticipated space processing payload requirements for the Spacelab and space shuttle orbiter planning activities. The six objectives generated by the study are defined. Concepts and requirements for space processing payloads to accommodate the performance of the shuttle-supported research phase are analyzed. Diagrams and tables of data are developed to show the experiments involved, the power requirements, and the payloads for shared missions

Space processing applications payload equipment study. Volume 2B: Payload interface analysis (power/thermal/electromagnetic compatibility)

As a part of the task of performing preliminary engineering analysis of modular payload subelement/host vehicle interfaces, a subsystem interface analysis was performed to establish the integrity of the modular approach to the equipment design and integration. Salient areas that were selected for analysis were power and power conditioning, heat rejection and electromagnetic capability (EMC). The equipment and load profiles for twelve representative experiments were identified. Two of the twelve experiments were chosen as being representative of the group and have been described in greater detail to illustrate the evaluations used in the analysis. The shuttle orbiter will provide electrical power from its three fuel cells in support of the orbiter and the Spacelab operations. One of the three shuttle orbiter fuel cells will be dedicated to the Spacelab electrical power requirements during normal shuttle operation. This power supplies the Spacelab subsystems and the excess will be available to the payload. The current Spacelab sybsystem requirements result in a payload allocation of 4.0 to 4.8 kW average (24 hour/day) and 9.0 kW peak for 15 minutes

Space processing applications payload equipment study. Volume 2D: SPA supplemental power and heat rejection kit

The design and application of a supplementary power and heat rejection kit for the Spacelab are discussed. Two subsystems of electric power and thermal control were analyzed to define the requirements for the power and heat rejection kit (PHRK). Twelve exemplary experiments were defined and power timelines were developed. From these timeline, the experiment requirements for sustained power, peak power, and energy were determined. The electrical power subsystem of the PHRK will consist of two fuel cells, oxygen and hydrogen reactant tank assemblies, water storage tanks, plumbing, cabling, and inverters to convert the nominal 28 volt dc fuel cell output to ac power

Space processing applications payload equipment study. Volume 3: Programmatics

The programmatic aspects of the space processing applications program and the methods of accommodating SPA payloads aboard the Shuttle/Spacelab host vehicle are discussed. An examination of the NASA traffic model shows that there exists a potential for 178 SPA payloads from the overall total of 727 flights specified. This could represent up to one quarter of the total shuttle flights during the 12-year-long period covered by the traffic model. The SPA payload will range from austere for shared flight opportunities to dedicated where space processing will encompass the total flight payload allocations. The major modes of use to SPA will include dedicated Spacelab missions, shared Spacelab missions and shared automated payloads attached to the pallet with the necessary control and display equipment in the host vehicle. Several layout drawings and artist's renderings have been completed to illustrate the various potential configurations available to accommodate the SPA payload equipment

Ferromagnetic resonance force microscopy on microscopic cobalt single layer films

We report mechanical detection of ferromagnetic resonance signals from microscopic Co single layer thin films using a magnetic resonance force microscope (MRFM). Variations in the magnetic anisotropy field and the inhomogeneity of were clearly observed in the FMR spectra of microscopic Co thin films 500 and 1000 angstrom thick and 40 X 200 micron^2 in lateral extent. This demonstrates the important potential that MRFM detection of FMR holds for microscopic characterization of spatial distribution of magnetic properties in magnetic layered materials and devices.Comment: 4 pages, 2 figures, RevTex. To be published in Applied Physics Letters, October 5, 199

Ferromagnetic resonance imaging of Co films using magnetic resonance force microscopy

Lateral one-dimensional imaging of cobalt (Co) films by means of microscopic ferromagnetic resonance (FMR) detected using the magnetic resonance force microscope (MRFM) is demonstrated. A novel approach involving scanning a localized magnetic probe is shown to enable FMR imaging in spite of the broad resonance linewidth. We introduce a spatially selective local field by means of a small, magnetically polarized spherical crystallite of yttrium iron garnet (YIG). Using MRFM-detected FMR signals from a sample consisting of two Co films, we can resolve the ∼20 μm lateral separation between the films. The results can be qualitatively understood by consideration of the calculated spatial profiles of the magnetic field generated by the YIG sphere

Perturbation of magnetostatic modes observed by ferromagnetic resonance force microscopy

Magnetostatic modes of yttrium iron garnet (YIG) films are investigated by ferromagnetic resonance force microscopy. A thin-film "probe" magnet at the tip of a compliant cantilever introduces a local inhomogeneity in the internal field of the YIG sample. This influences the shape of the sample's magnetostatic modes, thereby measurably perturbing the strength of the force coupled to the cantilever. We present a theoretical model that explains these observations; it shows that the tip-induced variation of the internal field creates either a local "potential barrier" or "potential well" for the magnetostatic waves. The data and model together indicate that local magnetic imaging of ferromagnets is possible, even in the presence of long-range spin coupling, through the introduction of localized magnetostatic modes predicted to arise from sufficiently strong tip fields

The magnetic-resonance force microscope: a new tool for high-resolution, 3-D, subsurface scanned probe imaging

The magnetic-resonance force microscope (MRFM) is a novel scanned probe instrument which combines the three-dimensional (3-D) imaging capabilities of magnetic-resonance imaging with the high sensitivity and resolution of atomic-force microscopy. It will enable nondestructive, chemical-specific, high-resolution microscopic studies and imaging of subsurface properties of a broad range of materials. The MRFM has demonstrated its utility for study of microscopic ferromagnets, and it will enable microscopic understanding of the nonequilibrium spin polarization resulting from spin injection. Microscopic MRFM studies will provide unprecedented insight into the physics of magnetic and spin-based materials. We will describe the principles and the state-of-the-art in magnetic-resonance force microscopy, discuss existing cryogenic MRFM instruments incorporating high-Q, single-crystal microresonators with integral submicrometer probe magnets, and indicate future directions for enhancing MRFM instrument capabilities

Mid-Infrared Ethane Emission on Neptune and Uranus

We report 8- to 13-micron spectral observations of Neptune and Uranus from the NASA Infrared Telescope Facility spanning more than a decade. The spectroscopic data indicate a steady increase in Neptune's mean atmospheric 12-micron ethane emission from 1985 to 2003, followed by a slight decrease in 2004. The simplest explanation for the intensity variation is an increase in stratospheric effective temperature from 155 +/- 3 K in 1985 to 176 +/- 3 K in 2003 (an average rate of 1.2 K/year), and subsequent decrease to 165 +/- 3 K in 2004. We also detected variation of the overall spectral structure of the ethane band, specifically an apparent absorption structure in the central portion of the band; this structure arises from coarse spectral sampling coupled with a non-uniform response function within the detector elements. We also report a probable direct detection of ethane emission on Uranus. The deduced peak mole fraction is approximately an order of magnitude higher than previous upper limits for Uranus. The model fit suggests an effective temperature of 114 +/- 3 K for the globally-averaged stratosphere of Uranus, which is consistent with recent measurements indicative of seasonal variation.Comment: Accepted for publication in ApJ. 16 pages, 10 figures, 2 table