Results 41 to 50 of about 23,959 (174)

Wilbur Norman Christiansen 1913-2007

, 2011
W. N. ('Chris') Christiansen was an innovative and influential radio astronomy pioneer. The hallmarks of his long and distinguished career in science and engineering, spanning almost five decades, were his inventiveness and his commitment to, and success
Frater, R. H., Goss, W. M.
core   +1 more source

Concentric circles and spiral configurations for large correlator arrays in radio astronomy [PDF]

, 2018
Aperture synthesis arrays are commonly used in radio astronomy to take images of radio point sources, with the planned Square Kilometre Array (SKA) being the most common example.
Abidin, Zamri Zainal, Chen, Zhizhang (David), Kiehbadroudinezhad, Samiramis, Kiehbadroudinezhad, Shahideh, Shahabi, Adib, Short, Ian C., Čada, Michael   +6 more
core   +2 more sources

Novel Insights on Ocean Internal Waves: Quantitative Surface Manifestations and Upper Ocean Layer Displacements From the Surface Water Ocean Topography Mission (SWOT) Measurements

Earth and Space Science, Volume 13, Issue 2, February 2026.
Abstract The Surface Water and Ocean Topography (SWOT) mission provides unprecedented high‐resolution simultaneous observations of both sea surface height anomalies and sea surface roughness. Specifically, it enables more precise analysis of strong internal waves. Off the Amazon Shelf, in the Indonesian Seas, and near the Mascarene Ridge, internal wave
V. Cheshm Siyahi, V. Kudryavtsev, B. Chapron, F. Collard   +3 more
wiley   +1 more source

First Resolution of Microlensed Images of a Binary-lens Event

The Astrophysical Journal
We resolve the multiple images of the binary-lens microlensing event ASASSN-22av using the GRAVITY instrument of the Very Large Telescope Interferometer (VLTI).
Zexuan Wu, Subo Dong, A. Mérand, Christopher S. Kochanek, Przemek Mróz, Jinyi Shangguan, Grant Christie, Thiam-Guan Tan, Thomas Bensby, Joss Bland-Hawthorn, Sven Buder, Frank Eisenhauer, Andrew P. Gould, Janez Kos, Tim Natusch, Sanjib Sharma, Andrzej Udalski, J. Woillez, David A. H. Buckley, I. B. Thompson, Karim Abd El Dayem, Anthony Berdeu, Jean-Philippe Berger, Guillaume Bourdarot, Wolfgang Brandner, Richard I. Davies, Denis Defrère, Catherine Dougados, Antonia Drescher, Andreas Eckart, Maximilian Fabricius, Helmut Feuchtgruber, Natascha M. Förster Schreiber, Paulo Garcia, Reinhard Genzel, Stefan Gillessen, Gernot Heißel, Sebastian Hönig, Mathis Houlle, Pierre Kervella, Laura Kreidberg, Sylvestre Lacour, Olivier Lai, Romain Laugier, Jean-Baptiste Le Bouquin, James Leftley, Bruno Lopez, Dieter Lutz, Felix Mang, Florentin Millour, Miguel Montargès, Hugo Nowacki, Mathias Nowak, Thomas Ott, Thibaut Paumard, Karine Perraut, Guy Perrin, Romain Petrov, Pierre-Olivier Petrucci, Nicolas Pourre, Sebastian Rabien, Diogo C. Ribeiro, Sylvie Robbe-Dubois, Matteo Sadun Bordoni, Daryl Santos, Jonas Sauter, Jules Scigliuto, Taro T. Shimizu, Christian Straubmeier, Eckhard Sturm, Matthias Subroweit, Calvin Sykes, Linda Tacconi, Frédéric Vincent, Felix Widmann, the GRAVITY+ collaboration   +75 more
doaj   +1 more source

First astronomical unit scale image of the GW Ori triple. Direct detection of a new stellar companion [PDF]

, 2011
Young and close multiple systems are unique laboratories to probe the initial dynamical interactions between forming stellar systems and their dust and gas environment.
Artymowicz, Bate, Berger, C. Bechet, Cohen, E. Pedretti, E. Thiébaut, F. Longa, F. Malbet, Hillenbrand, J. D. Monnier, J.-P. Berger, K. Perraut, M. Benisty, M. Lacasse, Mathieu, Menten, Monnier, Monnier, N. Carleton, Ochi, P. A. Schuller, P. Haguenauer, P. Kern, P. Labeye, P. Schloerb, Pauls, Pedretti, Pedretti, R. Millan-Gabet, S. Ragland, S. Renard, Sandstrom, Schloerb, Shevchenko, Siess, W. Traub   +36 more
core   +2 more sources

Real Heights of SuperDARN F Region Echoes Inferred From Electron Density Measurements by the Rankin Inlet and RISR‐C Radars

Radio Science, Volume 61, Issue 2, February 2026.
Abstract This study is one of the first attempts to estimate statistically the real height of SuperDARN F region echoes in the polar cap. To achieve this, measurements of the electron density in the scattering volume of the Rankin Inlet SuperDARN radar are compared with the electron density profiles measured by the incoherent scatter radar RISR‐C ...
Alexander V. Koustov, Mehdi Ghalamkarian Nejad, Hayden Fast, Pavlo V. Ponomarenko   +3 more
wiley   +1 more source

Photon orbital angular momentum and torque metrics for single telescopes and interferometers

, 2012
Context. Photon orbital angular momentum (POAM) is normally invoked in a quantum mechanical context. It can, however, also be adapted to the classical regime, which includes observational astronomy. Aims.
Elias, Harwit, N. M. Elias, Rau, Tamburini, Tamburini   +5 more
core   +1 more source

Accuracy Estimation of Astronomical Constants from Long Baseline Interferometer Observations [PDF]

Symposium - International Astronomical Union, 1974
Inherent in Very Long Baseline Interferometry (VLBI) is the potentiality of determining relative angular positions of radio sources to an accuracy which is superior to present methods by at least one order of magnitude. For VLBI observations such as time delay, fringe frequency and fringe phase the sensitivity to the uncertainties of astronomical ...
openaire   +1 more source

Six‐Component Electromagnetic Wave Measurements of Sprite‐Associated Lightning

Radio Science, Volume 61, Issue 2, February 2026.
Abstract Low frequency electromagnetic waves emitted by sprite‐producing lightning are normally measured using vertical electric fields or horizontal magnetic fields. Here we report for the first time the simultaneous measurement of electromagnetic waves from sprite‐producing lightning in all six electromagnetic field components Ex,Ey,Ez,Hx,Hy,andHz ...
Martin Füllekrug, Michael Kosch, Gavin Dingley, Xue Bai, Liliana Macotela   +4 more
wiley   +1 more source

High‐Latitude Electrodynamics and Thermospheric Density Variations During the 2024 Gannon Storm

Space Weather, Volume 24, Issue 2, February 2026.
Abstract This study investigates high‐latitude electrodynamics and thermospheric density variations during the 2024 Gannon's storm. First, the auroral precipitation module of Auroral Spectra and High‐Latitude Electric field variabilitY, ASHLEY‐A, is improved to more accurately capture the location of auroral precipitation observed during this ...
Qingyu Zhu, Sarah Vines, Marc Hairston, Yun‐Ju Chen, Phillip Anderson, Cheng Sheng, Yue Deng   +6 more
wiley   +1 more source