Speaker: Dr. Laurent Loinard, Institute of Radio Astronomy and Astrophysics, National Autonomous University of Mexico
Date/Time: February 14, 2025 / 12 noon central.
Location: Loomis 236
Zoom: https://illinois.zoom.us/j/82318062756?pwd=M3g1MFF6cytsOWFEbmU0UW1XWVoxQT09
Title: Black hole imaging and astrometry with the next generation of radio interferometers
Abstract: Very Long Baseline Interferometry (VLBI) is intimately linked to black holes and their astrometry. This relation goes both ways: VLBI astrometry has, for instance, enabled exquisitely accurate determinations of (i) black hole properties through precise distance measurements, (ii) the motion of the supermassive black hole at the center of the Milky Way, and (iii) the (local) Hubble constant value thanks to megamaser sources. Conversely, distant black holes are the anchors used for all VLBI astrometry. In this colloquium, I will provide a review of these topics, and discuss how the intimate relationship between black holes and astrometry will change with the advent of the future generation of VLBI arrays (particularly the ngEHT and the ngVLA).