The Celestial Frame and the Weighting of the Celestial Pole Offsets in the Computation of VLBI-Based Corrections for the Main Lunisolar Nutation Terms [PDF]
Sensors, 2021 Very long baseline interferometry (VLBI) is the only technique in space geodesy that can determine directly the celestial pole offsets (CPO). In this paper, we make use of the CPO derived from global VLBI solutions to estimate empirical corrections to ...
Víctor Puente, Marta Folgueira
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Probing a southern hemisphere VLBI Intensive baseline configuration for UT1 determination [PDF]
Earth, Planets and Space, 2022 The deviation of Universal Time from atomic time, expressed as UT1−UTC, reflects the irregularities of the Earth rotation speed and is key to precise geodetic applications which depend on the transformation between celestial and terrestrial reference ...
Sigrid Böhm +8 more
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Detection of a New Large Free Core Nutation Phase Jump [PDF]
Sensors, 2022 We announce the detection of a new large jump in the phase of the free core nutation (FCN). This is only the second such large FCN phase jump in more than thirty years of FCN monitoring by means of a very long baseline interferometry (VLBI) technique ...
Zinovy Malkin +2 more
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Radio Astronomical Antennas in the Central African Region to Improve the Sampling Function of the VLBI Network in the SKA Era? [PDF]
Sensors, 2022 On the African continent, South Africa has world-class astronomical facilities for advanced radio astronomy research. With the advent of the Square Kilometre Array project in South Africa (SA SKA), six countries in Africa (SA SKA partner countries) have ...
Marcellin Atemkeng +4 more
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The Astrophysical Journal Supplement Series, 2022 Abstract High-redshift radio sources provide plentiful opportunities for studying the formation and evolution of early galaxies and supermassive black holes. However, the number of known radio-loud active galactic nuclei (AGN) above redshift 4 is rather limited.
Máté Krezinger +9 more
openaire +7 more sources
A New Very Long Baseline Interferometry Method Based on the Uplink Signal
IEEE Access, 2020 Very long baseline interferometry (VLBI) is widely used for astronomical observations and navigation of deep space receivers. To solve the problems of the downlink signal being excessively weak to be received and the excessively large acquisition time, a
Linshan Xue, Weiren Wu, Xue Li
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Optical frequency comb integration in radio telescopes: advancing signal generation and phase calibration [PDF]
Light: Science & ApplicationsVery long baseline interferometry (VLBI) enables high-angular-resolution observations in astronomy and geodesy by synthesizing a virtual telescope with baselines spanning hundreds to thousands of kilometres. Achieving high instrumental phase stability in
Minji Hyun +10 more
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Sphero-Conical Modeling for the Estimation of Very Long Baseline Interferometry Invariant Point [PDF]
Sensors, 2022 A geodetic reference frame is a fundamental element in geoinformation fields such as autonomous navigation and digital twins. The international terrestrial reference frame is established and maintained using several space-geodetic techniques, including ...
Tae-Suk Bae, Chang-Ki Hong
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Promoting Earth-Based Radar Astronomical Observations of the Moon [PDF]
Sensors, 2020 Earth-based radar astronomical observations provide information on surface characteristics, orbits, and rotations for a wide variety of solar system objects.
Jing Sun +8 more
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Software and Techniques for VLBI Data Processing and Analysis
Universe, 2022 Very-long-baseline interferometry (VLBI) is a challenging observational technique, which requires in-depth knowledge about radio telescope instrumentation, interferometry, and the handling of noisy data.
Michael Janssen +2 more
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