On the prospects of imaging Sagittarius A* from space
Abstract
Very Long Baseline Interferometry (VLBI) at sub-millimeter waves has the potential to image the shadow of the black hole in the Galactic Center, Sagittarius A* (Sgr A*), and thereby test basic predictions of the theory of general relativity. We investigate the imaging prospects of a new Space VLBI mission concept. The setup consists of two satellites in polar or equatorial circular Medium-Earth Orbits with slightly different radii, resulting in a dense spiral-shaped uv-coverage with long baselines, allowing for extremely high-resolution and high-fidelity imaging of radio sources. We simulate observations of a general relativistic magnetohydrodynamics model of Sgr A* for this configuration with noise calculated from model system parameters. After gridding the uv-plane and averaging visibilities accumulated over multiple months of integration, images of Sgr A* with a resolution of up to 4 μ as could be reconstructed, allowing for stronger tests of general relativity and accretion models than with ground-based VLBI.
- Publication:
-
Perseus in Sicily: From Black Hole to Cluster Outskirts
- Pub Date:
- 2020
- DOI:
- 10.1017/S1743921318007676
- arXiv:
- arXiv:2005.01339
- Bibcode:
- 2020IAUS..342...24R
- Keywords:
-
- Galaxy: center;
- techniques: interferometric;
- techniques: high angular resolution;
- Astrophysics - Instrumentation and Methods for Astrophysics;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 4 pages, 4 figures, published in Proceedings IAU Symposium No. 342, 2018