Laser Ranging and Very-Long-Baseline Interferometry for Geodetic Applications

Laser Ranging and Very-Long-Baseline Interferometry for Geodetic Applications PDF Author: Irwin I. Shapiro
Publisher:
ISBN:
Category :
Languages : en
Pages : 7

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Book Description
Three distinct tasks were undertaken to advance the application of space techniques to the measurement of geodetic parameters: error analyses were performed to estimate the accuracy with which the locations of satellite tracking stations and the motion of the earth's pole may be determined from laser-ranging observations of the LAGEOS satellite; a numerical model of the moon's rotation was developed to support the analysis of lunar laser ranging observations; and a very-long-baseline interferometry (VLBI) system was constructed and installed at the Onsala Space Observatory in Sweden for use in a program to monitor the earth's rotation through observations of extragalactic radio sources. The details of this work have been described in three previously published reports. (Author).

Laser Ranging and Very-Long-Baseline Interferometry for Geodetic Applications

Laser Ranging and Very-Long-Baseline Interferometry for Geodetic Applications PDF Author: Irwin I. Shapiro
Publisher:
ISBN:
Category :
Languages : en
Pages : 7

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Book Description
Three distinct tasks were undertaken to advance the application of space techniques to the measurement of geodetic parameters: error analyses were performed to estimate the accuracy with which the locations of satellite tracking stations and the motion of the earth's pole may be determined from laser-ranging observations of the LAGEOS satellite; a numerical model of the moon's rotation was developed to support the analysis of lunar laser ranging observations; and a very-long-baseline interferometry (VLBI) system was constructed and installed at the Onsala Space Observatory in Sweden for use in a program to monitor the earth's rotation through observations of extragalactic radio sources. The details of this work have been described in three previously published reports. (Author).

Analysis of Laser Ranging and VLBI (Very Long Baseline Interferometry) Observations for Geodetic Purposes

Analysis of Laser Ranging and VLBI (Very Long Baseline Interferometry) Observations for Geodetic Purposes PDF Author: United States. National Technical Information Service
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Very Long Baseline Interferometry

Very Long Baseline Interferometry PDF Author: Marcello Felli
Publisher: Springer Science & Business Media
ISBN: 9400924283
Category : Science
Languages : en
Pages : 436

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Book Description
The quest for high resolution has preoccupied radio astronomers ever since radio waves were first detected from space fifty years ago. This venture was par ticularly stimulated by the discovery of quasars, and led to the development of interferometer techniques using baselines of transglobal dimensions. These meth ods have become known as Very Long Baseline Interferometry (VLBI). Arrays of radio telescopes situated all over the Earth (or even in space) are regularly used for researches in radio astronomy, reaching resolutions as small as a fraction of a milli arcsecond. The technique also allows the measurement of the positions of the radio telescopes to a few millimeters and so VLBI has become a major tool in geodesy and the study of the rotation of the Earth. VLBI has now passed the pioneer stage and is becoming a standard facility available to astronomers and geodesists, requiring the coordination of the operations of indpendently owned radio telescopes around the world. In Europe observatories from England, Federal Republic of Germany, France, Italy, Poland, Sweden and The Netherlands are coordinated in their VLBI activity by the European VLBI Network Consortium (EVN). The Programme Committee of the EVN allocates time to scientific projects on a routine basis three times a year. The Unites States has a similar arrangement of a network of independent radio observatories, and joint experiments using 'Global Network' are often made.

Analysis of Laser Ranging and VLBI Observations for Geodetic Purposes

Analysis of Laser Ranging and VLBI Observations for Geodetic Purposes PDF Author: I. I. Shapiro
Publisher:
ISBN:
Category :
Languages : en
Pages : 18

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Book Description
From three (Very Long Baseline Interferometry) VLBI experiments carried out in 1977 and 1978, the distances between the antenna at Onsala (Sweden) and radio telescopes at Haystack (Massachusetts), Green Bank (West Virginia) and Owens Valley (California) have been determined with formal standard errors as small as a few centimeters and repeatability generally within the 99% confidence interval of the root-sum-squares of these standard errors. Overall it appears that subdecimeter precision has been achieved in these estimates of baseline lengths. Using these data, we have also determined changes in UT1 and in the x and y components of polar motion. (Author).

Precise Geodetic Infrastructure

Precise Geodetic Infrastructure PDF Author: National Research Council
Publisher: National Academies Press
ISBN: 0309163293
Category : Science
Languages : en
Pages : 157

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Book Description
Geodesy is the science of accurately measuring and understanding three fundamental properties of Earth: its geometric shape, its orientation in space, and its gravity field, as well as the changes of these properties with time. Over the past half century, the United States, in cooperation with international partners, has led the development of geodetic techniques and instrumentation. Geodetic observing systems provide a significant benefit to society in a wide array of military, research, civil, and commercial areas, including sea level change monitoring, autonomous navigation, tighter low flying routes for strategic aircraft, precision agriculture, civil surveying, earthquake monitoring, forest structural mapping and biomass estimation, and improved floodplain mapping. Recognizing the growing reliance of a wide range of scientific and societal endeavors on infrastructure for precise geodesy, and recognizing geodetic infrastructure as a shared national resource, this book provides an independent assessment of the benefits provided by geodetic observations and networks, as well as a plan for the future development and support of the infrastructure needed to meet the demand for increasingly greater precision. Precise Geodetic Infrastructure makes a series of focused recommendations for upgrading and improving specific elements of the infrastructure, for enhancing the role of the United States in international geodetic services, for evaluating the requirements for a geodetic workforce for the coming decades, and for providing national coordination and advocacy for the various agencies and organizations that contribute to the geodetic infrastructure.

Very Long Baseline Interferometry and Geodetic Applications

Very Long Baseline Interferometry and Geodetic Applications PDF Author: David Neil McLintock
Publisher:
ISBN:
Category : Base measuring
Languages : en
Pages :

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Very Long Baseline Interferometry and Geodetic Applications

Very Long Baseline Interferometry and Geodetic Applications PDF Author: D. N. McLintock
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Proposed Satellite Laser Ranging and Very Long Baseline Interferometry Sites for Crustal Dynamic Investigations

Proposed Satellite Laser Ranging and Very Long Baseline Interferometry Sites for Crustal Dynamic Investigations PDF Author: Paul D. Lowman
Publisher:
ISBN:
Category : Geodesy
Languages : en
Pages : 59

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Geodetic and Astrometric Applications of Very Long Baseline Interferometry

Geodetic and Astrometric Applications of Very Long Baseline Interferometry PDF Author: Hans Franz Hinteregger
Publisher:
ISBN:
Category : Astronomical geography
Languages : en
Pages : 167

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On Principles, Methods and Recent Advances in Studies Towards a Gps-Based Control System for Geodesy and Geodynamics

On Principles, Methods and Recent Advances in Studies Towards a Gps-Based Control System for Geodesy and Geodynamics PDF Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781723241215
Category :
Languages : en
Pages : 114

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Book Description
Although Very Long Baseline Interferometry (VLBI) and Satellite Laser Ranging (SLR) are becoming increasingly important tools for geodynamic studies, their future role may well be fulfilled by using alternative techniques such as those utilizing the signals from the Global Positioning System (GPS). GPS, without the full implementation of the system, already offers a favorable combination of cost and accuracy and has consistently demonstrated the capability to provide high precision densification control in the regional and local areas of the VLBI and SLR networks. This report reviews VLBI and SLR vis-a-vis GPS and outlines the capabilities and limitations of each technique and how their complementary application can be of benefit to geodetic and geodynamic operations. It demonstrates, albeit with a limited data set, that dual-frequency GPS observations and interferometric type analysis techniques make possible the modelling of the GPS orbits for several days with an accuracy of a few meters. The use of VLBI or SLR sites as fiducial stations together with refinements in the orbit determination procedures can greatly reduce the systematic errors in the GPS satellite orbits used to compute the positions of non-fiducial locations. In general, repeatability and comparison with VLBI of the GPS determined locations are of the order of between 2 parts in 10 to the 7th power and 5 parts in 10 to the 8th power for baseline lengths less than 2000 km. This report is mainly a synthesis of problems, assumptions, methods and recent advances in the studies towards the establishment of a GPS-based system for geodesy and geodynamics and is one phase in the continuing effort for the development of such a system. To some, including the author, it seems reasonable to expect within the next few years that more evidence will show GPS to be as a powerful and reliable a tool as mobile VLBI and SLR are today, but largely more economical. Delikaraoglou, Demitris Goddard Space Flight Center GL...