Evidence for magnetic field aligned currents during the substorms of March 18, 1969
Magnetic field aligned currents during 18 March 1969 substorms, observing electric field by Ba plasma cloud motion for magnetic perturbation field
Akasofu, S.-I.↗
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The influence of field-aligned currents on auroral electron temperatures
Auroral electron temperature, noting field aligned energy transport current effects
Jones, R. A.↗
Field aligned continuity of Hall current electrojets and other consequences of density gradients in the auroral ionosphere
Polar cap magnetic variation mechanism based on electric field aligned continuity of Hall current auroral electrojets, noting ionospheric electron density gradients effects
Heppner, J. P.↗
MESS /Misalignment Estimation Software System/ for in-flight alignment and calibration of spacecraft attitude sensors
Misalignment estimation software system /MESS/ for in-flight celestial and inertial reference attitude sensor alignment and calibration on OAO
Desjardins, R.↗
Solar experiment alignment system
Sensor system determines absolute alignment of optical axis of experiment package relative to solar vector and provides control information to permit pointing experiment anywhere on solar disc to absolute accuracy of the order of two arc seconds in center and five arc seconds on limb.
Fain, D. L.↗
Optical alignment of electrodes on electrical discharge machines
Shadowgraph system projects magnified image on screen so that alignment of small electrodes mounted on electrical discharge machines can be corrected and verified. Technique may be adapted to other machine tool equipment where physical contact cannot be made during inspection and access to tool limits conventional runout checking procedures.
Boissevain, A. G.↗
Alignment microscope for rotating laser scanner
Microscopic assembly for alignment of rotary laser focuses on small film area along scan line at oblique angle. Suitable choice of angle and location of optical components project laser beam line as X coordinate reticle. Coordination with horizontal recticle line included microscope facilitates Y coordinate position indexing.
Maciel, A., Jr.↗
A method for star vector determination from alignment optical telescope sighting
A method is described for determining the measured star vector in LM body coordinates when the measurement data consist of a spiral measurement, a cusor measurement, and a time associated with each measurement. The method is defined from alignment optical telescope (AOT) sightings from the LM on the lunar surface. This formulation will be coded into the real-time computer complex off-line AOT and gravity (AOT+G) bench program, the Gravity-Optics LM Attitude and Position (GOLAP) program.
Crigler, S. W.↗
Apollo experience report: Onboard navigational and alignment software
The onboard navigational and alignment routines used during the nonthrusting phases of an Apollo mission are discussed as to their limitations, and alternate approaches that have more desirable capabilities are presented. A more efficient procedure for solving Kepler's equation, which is used in the calculation of Kepler's problem and Lambert's problem is included, and a sixth-order predictor scheme with a Runge-Kutta starter is recommended for numerical integration. The extension of the rendezvous navigation state to include angle biases and the use of a fixed coordinate system is also evaluated.
Savely, R. T.↗
Zero gravity shadow shield aligner
Apparatus for aligning shadow shields and cryogenic storage tanks in outer space with the sun
Howard, F. S.↗
Hanle-effect mean-life measurements on aligned fast ions.
Mean lives of several levels of the first two ionized states of argon were obtained by Hanle-effect measurements on the fast-beam particles, following coherent alignment of the magnetic substates by beam-foil interaction. The g factors of the levels were obtained by observation of quantum beats. Mean lives are compared with results of the usual beam-foil mean-life measurement technique. We show that the Hanle effect can sometimes clarify beam-foil results.
Church, D. A.↗
Automated cloud tracking using precisely aligned digital ATS pictures.
Discussion of the interactive man-computer system (WIMDCO) for measuring cloud motion from ATS pictures. The multipicture model of ATS navigation is used for consecutive ATS digital picture alignment to provide the required precision in cloud motion measurements by automated tracking techniques. Cloud motion is measured by tracking clouds between two digital pictures with the aid of two-dimensional cross correlation analysis. The fast Fourier transform method and other programming techniques are used for time and cost minimization. Cloud motion vectors were computed over three time intervals in July, 1969. The EW and NS components were reproducible within roughly 2 knots.
Smith, E. A.↗
A synoptic study of the nature and effects of field aligned low energy electron precipitation in the auroral regions
A synoptic study is presented of field-aligned precipitation events observed during a 16-month period, representing a full 4 pi precession of the satellite orbital plane in magnetic local time. The morphology of this type of precipitation, its nature, and relationships between this phenomenon and other geophysical events are discussed in the context of the 16-month data base.
Berko, F. W.↗
Seasonal and altitude variations in field-aligned precipitation occurrence
Data from more than 7500 orbits of the polar-orbiting satellite OGO-4 have been analyzed to determine the existence of seasonal, altitude, or universal time differences in the occurrence of field-aligned electrons. Unexpected variations in frequency of occurrence have been found at different altitudes and in different seasons. In particular, the probability of observing this phenomenon at high latitudes was found to be greatest in the winter months at the highest altitudes attained by OGO-4. A localized parallel electric field acceleration mechanism is presented which could account for the particle observations.
Berko, F. W.↗
Real-time Optical Alignment and Diagnostic System (ROADS)
The ultimate and most frequent usage of ROADS will be the alignment of subassemblies (collector and collimator) prior to their installation in a chamber. The system as designed has inherent associated capabilities well applied to acceptance testing of the No. 4 mirror, prediction of in-chamber performance, generation of a catalog of test results and other data, providing data for the plotting of isointensity lines, and other applications which are discussed. The ROADS system will collect, process, display, analyze, and retain data as required for components, partial subassemblies, complete subassemblies, complete modules, and multimodular arrays.
Source record↗
Space shuttle GN and C equation document no. 20: Fine alignment gyro torquing angles
The procedure for aligning the inertial reference unit of the space shuttle by celestial references is discussed. The gyro torquing angles required to go from the present stable member to the desired stable member are determined. The inputs are the transformation matrix from the reference to the desired stable member coordinates and the unit vectors to the two target stars in both the reference and present stable member coordinates. The equations involved in establishing the reference are developed.
St.amand, J.↗
Collimator of multiple plates with axially aligned identical random arrays of apertures
A collimator is disclosed for examining the spatial location of distant sources of radiation and for imaging by projection, small, near sources of radiation. The collimator consists of a plurality of plates, all of which are pierced with an identical random array of apertures. The plates are mounted perpendicular to a common axis, with like apertures on consecutive plates axially aligned so as to form radiation channels parallel to the common axis. For near sources, the collimator is interposed between the source and a radiation detector and is translated perpendicular to the common axis so as to project radiation traveling parallel to the common axis incident to the detector. For far sources the collimator is scanned by rotating it in elevation and azimuth with a detector to determine the angular distribution of the radiation from the source.
Hoover, R. B.↗
Eutectic superalloys strengthened by aligned delta, Ni3Cb lamellae, gamma-prime, Ni3Al precipitates and reduced interlamellar spacing.
Monovariant eutectic alloys, located on the liquidus trough between the binary eutectic gamma, Ni - delta, Ni3Cb and the ternary eutectic gamma, Ni - gamma-prime, Ni3Al - delta, Ni3Cb, were identified which permitted the production of aligned lamellae within a nickel solid solution matrix containing the precipitate gamma-prime. These alloys exhibited great insensitivity in their composite microstructures to solidification parameters such as growth rate temperature gradient, and were found to be remarkably uniform in composition along their length.
Lemkey, F. D.↗