Results 51 to 60 of about 27,177 (193)
Symposium - International Astronomical Union, 2001 I briefly review the means by which VLBI observations can determine the position, proper motion, and parallax of a pulsar, consider a subset of the applications of such results, and highlight recent developments in pulsar gating at JIVE.
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Decoherence in LOFAR-VLBI beamforming [PDF]
Astronomy & Astrophysics, 2020 We show that the use of a superstation (a phased array created using multiple stations of an interferometric array) created in post-processing for LOFAR-VLBI observations introduces a direction-dependent loss of signal in the image. We show this effect using simulations and real data.
Bonnassieux E. +3 more
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Earth and Space Science, Volume 12, Issue 10, October 2025.Abstract High‐precision Earth Rotation Parameter (ERP) products often experience delays that range from several days to weeks. The use of precise forecasting models can effectively compensate for the impact of such delays. Based on a systematic analysis of the forecasting capabilities of the traditional harmonic least squares fitting and autoregressive
Chen Ren +4 more
wiley +1 more source
The Gould's Belt Distances Survey
, 2012 Very Long Baseline Interferometry (VLBI) observations can provide the position of compact radio sources with an accuracy of order 50 micro-arcseconds. This is sufficient to measure the trigonometric parallax and proper motions of any object within 500 pc
Loinard, Laurent
core +1 more source
International Astronomical Union Colloquium, 1990 AbstractVLBI observations using a satellite in earth orbit and ground antennas in Japan and Australia were conducted in 1986, 1987, and 1988. Sources were detected on space-ground baselines at both observing frequencies: 2.3 and 15 GHz. The coherence on space-ground baselines for 340 s was 90% at 2.3 GHz and 76% at 15 GHz.
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Estimation and Attribution of Horizontal Land Motion Measured by the Greenland GNSS Network
Journal of Geophysical Research: Solid Earth, Volume 130, Issue 9, September 2025.Abstract Horizontal land motion, as observed by geodetic techniques such as Global Navigation Satellite Systems (GNSS), is generally dominated by tectonic plate movement. However, in regions that are currently or formerly glaciated, such as Greenland, the deformation of the solid Earth due to surface loading complicates the separation of tectonic and ...
D. Longfors Berg +6 more
wiley +1 more source
Modeling Nearby Low-Luminosity Active-Galactic-Nucleus Jet Images at All VLBI Scales
Galaxies, 2022 Relativistic jets from nearby low-luminosity active-galactic-nuclei (LLAGN) were observed by Very-Long Baseline Interferometry (VLBI) across many orders of magnitude in space, from milliparsec to sub-parsec scales, and from the jet base in the vicinity ...
Hung-Yi Pu +2 more
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Proceedings of 8th European VLBI Network Symposium — PoS(8thEVN), 2007 3 pages, 2 figures, to appear in the proceedings of the 8th EVN symposium held in Torun, Poland, September ...
Doi, Akihiro +17 more
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A Review of Machine Learning‐Based Ionospheric Spatial and Temporal Modeling
Journal of Geophysical Research: Machine Learning and Computation, Volume 2, Issue 3, September 2025.Abstract The ionosphere introduces disturbances and errors in radio signals for satellite communication and navigation, requiring precise modeling to mitigate these effects. However, accurate ionospheric modeling faces challenges due to the complex spatio‐temporal variations caused by intricate coupling with the lower atmosphere and Earth's magnetic ...
Shuyin Mao +2 more
wiley +1 more source
Earth rotation variations observed by VLBI and the Wettzell “G” ring laser during the CONT17 campaign [PDF]
Advances in Geosciences, 2019 The VLBI (Very Long Baseline Interferometry) technique can provide the full set of parameters needed for the transformation between celestial and terrestrial reference frames with high accuracy.
S. Böhm +5 more
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