From Wikipedia, the free encyclopedia
Using stars to measure Earth
Geodetic astronomy
or
astronomical geodesy
(
astro-geodesy
) is the application of
astronomical
methods into
geodetic networks
and other technical projects of
geodesy
.
Applications
[
edit
]
The most important applications are:
Measuring techniques
[
edit
]
Important measuring techniques are:
The
accuracy
of these methods depends on the
instrument
and its spectral wavelength, the measuring or scanning method, the time amount (versus economy), the
atmospheric
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.:
Astrogeodetic
leveling
is a local
geoid determination
method based on
vertical deflection
measurements. Given a starting value at one point, determining the
geoid undulations
for an area becomes a matter for simple
integration
of vertical deflection, as it represents the horizontal
spatial gradient
of the geoid undulation.
See also
[
edit
]
References
[
edit
]
External links
[
edit
]
|
---|
Overview
| |
---|
Subfields
| |
---|
Physical
phenomena
| |
---|
Related disciplines
| |
---|
|