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arXiv · 2005.01339

On the prospects of imaging Sagittarius A* from space

Freek Roelofs·Heino Falcke·Christiaan Brinkerink·Monika Moscibrodzka·Leonid I. Gurvits·Manuel Martin-Neira·Volodymyr Kudriashov·Marc Klein-Wolt·Remo Tilanus·Michael Kramer·Luciano Rezzolla
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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.

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Freek Roelofs, Heino Falcke, Christiaan Brinkerink, Monika Moscibrodzka, Leonid I. Gurvits, Manuel Martin-Neira, Volodymyr Kudriashov, Marc Klein-Wolt, Remo Tilanus, Michael Kramer, Luciano Rezzolla. 2020-05-04. On the prospects of imaging Sagittarius A* from space. https://doi.org/10.1017/s1743921318007676

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