Results 71 to 80 of about 14,980 (205)

Evaluate the Prediction Level of Polar Motion Interpolation for 6 hr in Ideal and Real Environments

Earth and Space Science, Volume 13, Issue 1, January 2026.
Abstract With the increasing demands for global development, deep space exploration missions are taking place more frequently, rendering the traditional 24‐hr Polar Motion (PM) predictions inadequate for supporting the frequent operations of spacecraft.
Wei Miao, Xueqing Xu, Yonghong Zhou
wiley   +1 more source

The AUSTRAL VLBI observing program [PDF]

Journal of Geodesy, 2016
The AUSTRAL observing program was started in 2011, performing geodetic and astrometric very long baseline interferometry (VLBI) sessions using the new Australian AuScope VLBI antennas at Hobart, Katherine, and Yarragadee, with contribution from the Warkworth (New Zealand) 12 m and Hartebeesthoek (South Africa) 15 m antennas to make a southern ...
L. Plank, J. E. J. Lovell, J. N. McCallum, D. Mayer, C. Reynolds, J. Quick, S. Weston, O. Titov, S. S. Shabala, J. Böhm, T. Natusch, M. Nickola, S. Gulyaev   +12 more
openaire   +3 more sources

FinalKAN: A Dual‐Stream KAN Network Integrating Multisource Features for Radio Telescope Pointing Correction

Advances in Astronomy, Volume 2026, Issue 1, 2026.
This paper investigates the degradation of pointing accuracy in the Kunming 40‐m radio telescope due to long‐term equipment aging and environmental disturbances. Conventional linear pointing models are constrained by their linear modeling framework, making it difficult to accurately represent the nonlinear errors induced by temperature, wind speed, and
Yao He, Longfei Hao, Wei Dai, Fernando Aguado Agelet   +3 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, Keiichi Asada, Masanori Nakamura   +2 more
doaj   +1 more source

Multiwavelength VLBI observations of Sagittarius A* [PDF]

Astronomy & Astrophysics, 2010
14pages, 14 Figures, Accepted for publication in A& ...
Lu, R. -S., Krichbaum, T. P., Eckart, A., König, S., ~Kunneriath, D., Witzel, G., Witzel, A., Zensus, J. A.   +7 more
openaire   +2 more sources

A History of UNAVCO: Four Decades of Advancing Geodesy

Perspectives of Earth and Space Scientists, Volume 6, Issue 1, December 2025.
Abstract UNAVCO was a university‐governed consortium funded by the National Science Foundation (NSF), with support from the National Aeronautics and Space Administration (NASA) and the United States Geological Survey (USGS), to support geoscience research and education using geodesy.
Emily E. Zawacki, Donna J. Charlevoix, Charles M. Meertens, Jeffrey T. Freymueller, Tonie van Dam   +4 more
wiley   +1 more source

VERA’s 20 yr Evolution in Science and Technology

Galaxies
We review the past 20 yr evolution of VERA (VLBI Exploration of Radio Astrometry) in both science and techinology. VERA is a VLBI array in Japan which consists of four 20 m-diameter telescopes, originally dedicated to phase-referencing VLBI astrometry ...
Mareki Honma, Tomoya Hirota, Tomoaki Oyama, Akiharu Nakagawa   +3 more
doaj   +1 more source

Spectral Line VLBI Studies Using the ngEHT

Galaxies, 2023
Spectroscopy in the mm/sub-mm wavelength range is a powerful tool to study the gaseous medium in various astrophysical environments. The next generation Event Horizon Telescope (ngEHT) equipped with a wide-bandwidth backend system has great potential for
Dong-Jin Kim, Vincent Fish
doaj   +1 more source

VLBI Observations of the Nucleus of Centaurus A [PDF]

Symposium - International Astronomical Union, 1982
VLBI observations of the nucleus of Centaurus A have been made at three southern hemisphere observatories. Since Centaurus A is the nearest active galaxy, VLBI investigations are important because the physical processes in the nucleus can be studied in greater linear detail than in other similar galaxies.
R. A. Preston, A. E. Wehrle, D. D. Morabito, D. L. Jauncey, M. Batty, R. F. Haynes, A. E. Wright, G. D. Nicolson   +7 more
openaire   +1 more source

Globally Critical Infrastructure: The Unique Risks and Challenges

Risk Analysis, Volume 45, Issue 12, Page 4804-4817, December 2025.
ABSTRACT Critical infrastructure is typically identified at the national level. However, disruption to certain infrastructure systems, facilities, and assets can have negative consequences for global societies. Such globally critical infrastructure entails a distinct risk profile for both countries dependent on the infrastructure, and countries that ...
Zachary Kallenborn, Henry H. Willis
wiley   +1 more source