Results 101 to 110 of about 33,024 (227)

Evolution of the Termination Region of the Parsec-scale Jet of 3C 84 Over the Past 20 yr

The Astrophysical Journal
We present the kinematics of the parsec-scale jet in 3C 84 from 2003 November to 2022 June observed with the Very Long Baseline Array at 43 GHz. We find that the C3 component, a bright feature at the termination region of the jet component ejected from ...
Minchul Kam, Jeffrey A. Hodgson, Jongho Park, Motoki Kino, Hiroshi Nagai, Sascha Trippe, Alexander Y. Wagner   +6 more
doaj   +1 more source

VLBA Astrometry of the Galactic Double Neutron Stars PSR J0509+3801 and PSR J1930–1852: A Preliminary Transverse Velocity Distribution of Double Neutron Stars and its Implications

The Astrophysical Journal
The mergers of double neutron star (DNS) systems are believed to drive the majority of short γ -ray bursts (SGRBs), while also serving as production sites of heavy r -process elements.
Hao Ding, Adam T. Deller, Joseph K. Swiggum, Ryan S. Lynch, Shami Chatterjee, Thomas M. Tauris   +5 more
doaj   +1 more source

Spacecraft-spacecraft very long baseline interferometry. Part 1: Error modeling and observable accuracy [PDF]

In Part 1 of this two-part article, an error budget is presented for Earth-based delta differential one-way range (delta DOR) measurements between two spacecraft.
Border, J. S., Edwards, C. D., Jr.
core   +1 more source

Precision tracking systems of the immediate future: A discussion [PDF]

, 1972
The present status and future expectations of four satellite tracking systems, satellite-to-satellite tracking, lasers, very long baseline interferometry (VLBI) and geoceiver are briefly ...
Smith, D. E.
core   +1 more source

An accuracy assessment of Magellan Very Long Baseline Interferometry (VLBI) [PDF]

Very Long Baseline Interferometry (VLBI) measurements of the Magellan spacecraft's angular position and velocity were made during July through September, 1989, during the spacecraft's heliocentric flight to Venus. The purpose of this data acquisition and
Border, J. S., Engelhardt, D. B., Kronschnabl, G. R.   +2 more
core   +1 more source

The Subparsec-scale Structure and Evolution of Centaurus A. III. A Multi-epoch Spectral and Polarimetric VLBA Study

The Astronomical Journal
The Centaurus A radio galaxy, due to its proximity, presents itself as one of the few systems that allow the study of relativistic jet outflows at subparsec distances from the central supermassive black holes, with high signal to noise.
S. Prabu, S. J. Tingay, A. Bahramian, J. C. A. Miller-Jones, C. M. Wood, S. P. O’Sullivan   +5 more
doaj   +1 more source

Polar motion and UT1: Comparison of VLBI, lunar laser, satellite laser, satellite Doppler, and conventional astrometric determinations [PDF]

Very long baseline interferometry observations made with a 3900 km baseline interferometer (Haystack Observatory in Massachusetts to Owens Valley Observation in California) were used to estimate changes in the X-component of the position of the Earth's ...
Clark, T. A., Coates, R. J., Corey, B. E., Counselman, C. C., III, Hinteregger, H. F., King, R. W., Ma, C., Robertson, D. S., Ryan, J. W., Shapiro, I. I.   +9 more
core   +1 more source

The First Very Long Baseline Interferometric SETI Experiment

, 2012
The first Search for Extra-Terrestrial Intelligence (SETI) conducted with Very Long Baseline Interferometry (VLBI) is presented. By consideration of the basic principles of interferometry, we show that VLBI is efficient at discriminating between SETI ...
Avruch, Backus, Bastian, Batalha, Black, Blair, Borucki, Bracewell, Broderick, C. M. Trott, Deller, Deller, Drake, Fey, Fey, H. Rampadarath, Harp, J. S. Morgan, Kay, Kettenis, Korpela, Montebugnoli, Perryman, Rhee, S. J. Tingay, Shostak, Symons, Taylor, Thompson, Turnbull, Vogt, Wayth   +31 more
core   +1 more source

Phase versus delay in geodetic VLBI [PDF]

The conditions for the applicability of the phase observable in very long baseline interferometry are discussed and examples of adequate observation programs are given.
Campbell, J.
core   +1 more source

Very-Long-Baseline Interferometry [PDF]

, 2017
A. Richard Thompson, James M. Moran, George W. Swenson   +2 more
openaire   +1 more source