Digital zenith camera system for Astro-Geodetic applications in Turkey

Abstract

There are several current investigations on gravity field of the earth in Geodesy and Geophysics. Earth sciences and space researches are also interested in gravity studies. Geoid, which approximately has an equal potential to the potential of mean sea level, is the main datum for height systems and is used for coordinate transformation, reduction of measurements, subsurface density variations and similar scientific studies. Current studies focus on the determination of cm level geoid, in order to use Global Navigation Satellite Systems GNSS such as Continuously Operating Reference Stations CORS-TR/TUSAGA-Active in Turkey effectively. This study introduces general information about recent astro-geodetic observations performed by different institutions all over Europe. Furthermore, it also gives some details about data acquisition, instrumentation and processing technique that focuses on observation principle and new technologies used in modern Geodetic Astronomy. Finally, this study introduces the system design and the first observations of a Digital Zenith Camera System DZCS used in Istanbul, Turkey

Keywords

• Geodetic astronomy,Digital zenith camera systems,Vertical deflections,Geoid

Türkiye'deki Astro-Jeodezik uygulamalar için sayısal zenit kamera sistemi

Abstract

Jeodezi ve Jeofizik alanlarında yerin gravite alanının belirlenmesi ile ilgili pek çok güncel çalışma bulunmaktadır. Potansiyeli, ortalama deniz yüzeyi potansiyeline yakın olan jeopotansiyel yüzey “geoit”, bir düşey datum olarak yükseklik sistemlerinin temelini oluşturur ve bu nedenle, koordinat transformasyonu, ölçülerin indirgenmesi, yoğunluk araştırmaları ve benzeri çalışmalarda özel bir öneme sahiptir. Bir santimetre geoidinin belirlenmesi ile ilgili çalışmalar devam etmektedir. Bir cm-geoidi GNSS’den Türkiye için TUSAGA-Aktif rasyonel yararlanmanın temel koşuludur. Bu çalışmada güncel astro-jeodezik gözlemlere ilişkin Avrupa genelinde devam eden çalışmalara yer verilmiştir. Bu çalışma ayrıca veri elde etme, ölçme ekipmanları ve değerlendirme yöntemleri ile gözlem esasları ve Jeodezik Astronomide yeni teknolojiler ile ilgili gelişmeleri içermektedir. Bu çalışmanın son kısmında ise İstanbul’da tasarlanan ve ilk test gözlemleri gerçekleştirilen Sayısal Zenit Kamera Sistemi tanıtılmaktadır

Keywords

• Jeodezik astronomi,Sayısal zenit kameralar,Çekül sapmaları,Geoit

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