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The Estimation of Plate Motions by Astronomical Methods
Canadian Journal of Earth Sciences, 1972Some of the problems involved in the detection of plate motions by astronomical methods are discussed with particular reference to a Herstmonceux–Calgary cooperative program using photographic zenith tubes. Analysis of the observations obtained in 1969 and 1970 shows that several decades of continued observation may suffice with present techniques to ...
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Geometric method to measure astigmatism aberration at astronomical telescopes
Applied Optics, 2007A simple geometrical method to measure the aberration of astigmatism present in the wavefront that emerges from a telescope is presented. The method is based on the analysis of the external contour of the image of a slightly defocused star. An expression elliptical edge is obtained, which links the rms value of Z22 to the geometric parameters of the ...
Esteban, Luna +3 more
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Rate of Change Methods in Astronomical Surveying
Journal of the Surveying and Mapping Division, 1980A method is described whereby longitude, latitude and azimuth can be obtained by taking sights on the sun at short timed intervals. Both rate of change of altitude with time and rate of change of bearing with altitude can be used to calculate the observer’s position and the direction of the meridian.
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Astronomical methods and calculations
The Physics Teacher, 1987Agnes Acker +2 more
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Design method of an astronomical telescope with reduced sensitivity to misalignment
Applied Optics, 1994Approximate formulas are derived for the axial coma resulting from tilt and decenter of a surface and for the spherical aberration resulting from a change in its axial position. These expressions include terms that represent aberrations induced by the subsystem preceding the surface in addition to other terms that are intrinsic contributions from the ...
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Lenghu on the Tibetan Plateau as an astronomical observing site
Nature, 2021Chunguang Zhang +2 more
exaly
Methods for astronomical image restoration
Procedings of The XXXVIII Iberian Latin American Congress on Computational Methods in Engineering, 2017Ana Paula Abranches de Castro e Shiguemori +7 more
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