Basic Formulae for the Computation of the Deflection of the Vertical from Astronomical Star Observations,
Abstract
In this report we deal with new concepts for determining the astrogeodetic deflection of the vertical, in the sense that we determine the xi and eta deflection components completely independently of the knowledge of the astronomic coordinates, latitude and longitude, hence reducing the time and cost of field work. The first part of this paper is devoted to finding a relationship between the deflection components with respect to a star or stars positions. We have found that the xi and eta components are related to either the difference between the astronomic and geodetic star zenith distances; azimuths; parallactic angles, or are based on a star rate of change in azimuth and zenith distance with respect to time. Except for the last one, star pairs must be considered. In the second part of this paper, we consider a method that deals with the solution for the deflection components xi and eta from observation of star pairs, as function of the astronomic and geodetic zenith distances. The effect of errors in evaluating the deflection components xi and eta as well as the polar migration, are considered.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1985
- Accession Number
- ADA154912
Entities
People
- A. A. Baldini
Organizations
- Geospatial Research Laboratory