
Geodetic astronomy is the application of astronomy methods into networks and technical projects of geodesy. The most important topics are: * Establishment of geodetic datum systems (e.g. ED50) or at expeditions * apparent places of stars, and their proper motions * precise astronomical navigation * astro-geodetic geoid determination and * modelling the rock density of the topography and of geological layers in the subsurface * Satellite geodesy using the background of stars (see also astrometry and cosmic triangulation) * Monitoring of the Earth rotation and polar wandering * Contribution to the time system of physics and geosciences Important measuring techniques are: * Latitude and longitude determination by theodolites, tacheometers, astrolabes or zenith cameras * time and star positions by observation of star transits, e.g. by meridian circles (visual, photographic or CCD) * Azimuth measurements ** for the exact orientation of geodetic networks ** for mutual transformations between terrestrial and space methods ** for improved accuracy by means of "Laplace points" at special fixed points * Vertical deflection measurements and their use ** in geoid determination ** in mathematical reduction of very precise networks ** for geophysical and geological purposes (see above) * VLBI with radio sources (quasars) * Astrometry of stars by scanning satellites like Hipparcos or the future Gaia. The accuracy of these methods depends on the instrument and its spectral wavelength, the measuring or scanning method, the time amount (versus economy), the atmoshere situation, the stability of the surface resp. the satellite, on mechanical and temperature effects to the instrument, on the experience and skill of the observer, and on the accuracy of the physical-mathematical models. Therefore the accuracy reaches from 60" (navigation, ~1 mile) to 0,001" and better (a few cm; satellites, VLBI), e.g.: * vertical deflections and azimuths ±1" up to 0,1" * geoid determination & hight systems ca. 5 cm up to 0,2 cm * astronomical lat/lon and star positions ±1" up to 0,01" * Hipparcos star positions ±0,001" * VLBI quasar positions and Earth's rotation poles 0,001 to 0,0001" (cm...mm) ==See also== * Astronomy * satellite * electro-optics * tacheometer * triangulation * space techniques Geodesy Astronomy
See other meanings of words starting from letter:
Words begining with Geodetic_Astronomy:
Geodetic_astronomy
Geodetic astronomy
Geodetic astronomy is the application of astronomy methods into networks and technical projects of geodesy. The most important topics are: * Establishment of geodetic datum systems (e.g. ED50) or at expeditions * apparent places of stars, and their proper motions * precise astronomical navigation * astro-geodetic geoid determination and * modelling the rock density of the topography and of geological layers in the subsurface * Satellite geodesy using the background of stars (see also astrometry and cosmic triangulation) * Monitoring of the Earth rotation and polar wandering * Contribution to the time system of physics and geosciences Important measuring techniques are: * Latitude and longitude determination by theodolites, tacheometers, astrolabes or zenith cameras * time and star positions by observation of star transits, e.g. by meridian circles (visual, photographic or CCD) * Azimuth measurements ** for the exact orientation of geodetic networks ** for mutual transformations between terrestrial and space methods ** for improved accuracy by means of "Laplace points" at special fixed points * Vertical deflection measurements and their use ** in geoid determination ** in mathematical reduction of very precise networks ** for geophysical and geological purposes (see above) * VLBI with radio sources (quasars) * Astrometry of stars by scanning satellites like Hipparcos or the future Gaia. The accuracy of these methods depends on the instrument and its spectral wavelength, the measuring or scanning method, the time amount (versus economy), the atmoshere situation, the stability of the surface resp. the satellite, on mechanical and temperature effects to the instrument, on the experience and skill of the observer, and on the accuracy of the physical-mathematical models. Therefore the accuracy reaches from 60" (navigation, ~1 mile) to 0,001" and better (a few cm; satellites, VLBI), e.g.: * vertical deflections and azimuths ±1" up to 0,1" * geoid determination & hight systems ca. 5 cm up to 0,2 cm * astronomical lat/lon and star positions ±1" up to 0,01" * Hipparcos star positions ±0,001" * VLBI quasar positions and Earth's rotation poles 0,001 to 0,0001" (cm...mm) ==See also== * Astronomy * satellite * electro-optics * tacheometer * triangulation * space techniques Geodesy Astronomy
See other meanings of words starting from letter:
G
GA | GB | GC | GD | GE | GF | GH | GI | GJ | GK | GL | GM | GN | GO | GP | GR | GS | GT | GU | GW | GX | GY | GZ |Words begining with Geodetic_Astronomy:
Geodetic_astronomy
Sponsored links: praca, nurkowanie.
These materials are based on Wikipedia and licensed under the GNU FDL
YouTube.com videos better site than Turbo Tax 2007
