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
doaj +2 more sources
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
doaj +2 more sources
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
doaj +2 more sources
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
doaj +2 more sources
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
doaj +2 more sources
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
doaj +2 more sources
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
doaj +2 more sources
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
doaj +1 more source
Astrometric Apparent Motion of High-redshift Radio Sources
The Astronomical Journal, 2023 Radio-loud quasars at high redshift ( z ≥ 4) are rare objects in the universe and rarely observed with Very Long Baseline Interferometry (VLBI). But some of them have flux density sufficiently high for monitoring of their apparent position.
Oleg Titov +12 more
doaj +1 more source
VLBI Type Experimental Observation of GPS [PDF]
Journal of Astronomy and Space Sciences, 2010 As a preparatory study for Global Positioning System-Very Long Baseline Interferometry (GPS-VLBI) hybrid system, we examined if VLBI type observation of the GPS signal is realizable through a test experiment.
Younghee Kwak +6 more
doaj +1 more source