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Historical Review OfAstro-Geodetic Observations

In Serbia

Vukan Ogrizović

Belgrade University

Faculty Of Civil Engineering

Department Of Geodesy And Geoinformatics

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Geodesy & Astronomy

• Measurements and representation of the Earth, including its gravity field, in a 3D time-varying space

Geodesy [Vaníček, Krakiwsky, 1986.]

• Terrestrial (relative)• Satellite, gravimetric & astrometric (“absolute”)

Types of geodetic measurements

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Role Of Geodetic Astronomy

• Positioning of state geodetic networks• Orientation of networks• Tracing of long traverses

Historically

• Calibration basis for inertial systems• High-resolution geoid determination

Current tasks

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Astro-geodetic geoid

Astronomical levelling

Geoid undulations

B

AdsdN coscos

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Astro-geodetic work in Serbia

• Before 1st World War• Between WW1 & WW2• After WW2

Three phases

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First determinations

• Scientific work of Stevan Bošković in Pulkovo• Differences between surveys of Serbia and

neighbouring countries

Prehistory

• Different orientation of state networks• Neglected vertical deflections

Bošković’s conclusions

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Determinations of Bošković

• Measurements performed between 1900 and 1911• 30 latitude and 30 azimuths measured• Processing finished in 1952

Some details about measurements

• Wars between 1912 and 1920• Need for urgent topographic survey during wartime• Carrying all collected material through Albania to Corfu• Second World War

The time gap between measurements and processing

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Determinations of Bošković

• Two universal instruments Kern• 12 chronometers• aneroids• thermometers

Instruments used

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Between Wars

• Meridian arc measurements (22nd meridian)• Mean parallel 45°• Determinations of Belgrade longitude

Measurements held by Military Geographic Institute

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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After WW2

• Military geographic institute• Federal geodetic directorate• Astronomical observatory• Institute of geodesy

Relevant institutions

What was measured

• Laplace points (), 26 points• geoid points (), 33 points

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Today

• Intensive use of computers• Easier time keeping• Portability of equipment

Technical possibilities

Institutions working on geodetic problems

• Department of Geodesy & Geoinformatics• Governmental Geodetic Authority• Military Geographic Institute

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• Advanced approach to a standard astrometric method

• Need for portability - use of geodetic equipment

• GPS as time-keeping system

Equal Zenith Distances

1PPS

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• Modular construction

• Zenit-lot as an optical instrument

• CCD camera for star tracks registration

• GPS micro-controller

Observing Zenithal Stars

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Future

• Raising the integration level of modular systems• Incorporating electronic levels for interpretation the

horizontal surface• Device driver improvement

Improvement of measuring systems

• Lack of appropriate funding

Problem

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Thank you for your attention!

“There’s no dark side of the Moon, really. In the matter of fact, it’s all dark”