This document summarizes the historical use of astro-geodetic observations in Serbia over three phases: before World War 1, between the two world wars, and after World War 2. It describes the key figures who performed early measurements, such as Stevan Bošković, and the instruments that were used. It also outlines the transition to newer techniques using computers, portable equipment, and GPS for timekeeping. Finally, it discusses future improvements to measuring systems and challenges around funding.

1. Historical Review Of
Astro-Geodetic Observations
In Serbia
Vukan Ogrizović
Belgrade University
Faculty Of Civil Engineering
Department Of Geodesy And Geoinformatics
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2. Geodesy & Astronomy
Geodesy [Vaníček, Krakiwsky, 1986.]
• Measurements and representation of the Earth,
including its gravity field, in a 3D time-varying
space
Types of geodetic measurements
• Terrestrial (relative)
• Satellite, gravimetric & astrometric (“absolute”)
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3. Role Of Geodetic Astronomy
Historically
• Positioning of state geodetic networks
• Orientation of networks
• Tracing of long traverses
Current tasks
• Calibration basis for inertial systems
• High-resolution geoid determination
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4. Astro-geodetic geoid
Astronomical levelling
Geoid undulations
dN = − ∫ ( ξ cos α + η cos α ) ds
B
A
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5. Astro-geodetic work in Serbia
Three phases
• Before 1st World War
• Between WW1 & WW2
• After WW2
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6. First determinations
Prehistory
• Scientific work of Stevan Bošković in Pulkovo
• Differences between surveys of Serbia and
neighbouring countries
Bošković’s conclusions
• Different orientation of state networks
• Neglected vertical deflections
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7. Determinations of Bošković
Some details about measurements
• Measurements performed between 1900 and 1911
• 30 latitude and 30 azimuths measured
• Processing finished in 1952
The time gap between measurements and processing
• Wars between 1912 and 1920
• Need for urgent topographic survey during wartime
• Carrying all collected material through Albania to Corfu
• Second World War
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8. Determinations of Bošković
Instruments used
• Two universal instruments Kern
• 12 chronometers
• aneroids
• thermometers
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9. Between Wars
Measurements held by Military Geographic Institute
• Meridian arc measurements (22nd meridian)
• Mean parallel 45°
• Determinations of Belgrade longitude
Campaigns were a part of the International
determinations of longitudes in 1926 and 1933
• 40 points determined
• results published only for 21
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10. After WW2
Relevant institutions
• Military geographic institute
• Federal geodetic directorate
• Astronomical observatory
• Institute of geodesy
What was measured
• Laplace points (Φ, Λ, α), 26 points
• geoid points (Φ, Λ), 33 points
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11. Today
Technical possibilities
• Intensive use of computers
• Easier time keeping
• Portability of equipment
Institutions working on geodetic problems
• Department of Geodesy & Geoinformatics
• Governmental Geodetic Authority
• Military Geographic Institute
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12. Equal Zenith Distances
• Advanced approach to a standard
astrometric method
• Need for portability - use of
geodetic equipment
• GPS as time-keeping system
1PPS
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13. Observing Zenithal Stars
• Modular construction
• Zenit-lot as an optical instrument
• CCD camera for star tracks
registration
• GPS micro-controller
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14. Future
Improvement of measuring systems
• Raising the integration level of modular systems
• Incorporating electronic levels for interpretation the
horizontal surface
• Device driver improvement
Problem
• Lack of appropriate funding
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15. “There’s no dark side of the Moon, really.
In the matter of fact, it’s all dark”
Thank you for your attention!
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