Colloquium Abstract - Cigan - 2024Nov15

November 15, 2024

11:00am Mountain

Phil Cigan (USNO)

 

Reference Frames and Beyond: VLBI for Astrometry, Geodesy, and Astronomy

 

Abstract

Very Long Baseline Interferometry is a useful technique for creating extremely high-resolution astronomical images, but it is also a critical tool for astrometry and geodesy, to maintain our frames of reference on both land and sky.  The Celestial and Terrestrial Reference Frames, and the derived Earth Orientation Parameters, have a broad range of navigational, scientific, and commercial importance. The United States Naval Observatory is a key player in international VLBI projects that support these efforts, and is a center of vigorous research aimed at understanding the underlying properties of the AGN reference sources used in this work and more. This presentation will give a brief overview of the use of VLBI for reference frames, astrometry, and geodesy from the perspective of a traditional astronomer, highlight some recent research into the positional variability of the reference sources, and mention several interesting projects at USNO that will be of interest to the astronomy community.


Local Host: Jay Blanchard

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