Analysis of information sources in references of the Wikipedia article "Чорная дзірка" in Belarusian language version.
The new orbital data now definitely exclude a dark cluster of astrophysical objects (e.g., neutron stars) or a ball of 10—60 keV fermions as possible configurations of the central mass concentration. The only nonblack hole configuration is a ball of hypothetical, heavy bosons, which would not be stable, however. The gravitational potential in the central light year of the Galactic center thus is almost certainly dominated by a massive black hole associated with Sgr A*.
The new orbital data now definitely exclude a dark cluster of astrophysical objects (e.g., neutron stars) or a ball of 10—60 keV fermions as possible configurations of the central mass concentration. The only nonblack hole configuration is a ball of hypothetical, heavy bosons, which would not be stable, however. The gravitational potential in the central light year of the Galactic center thus is almost certainly dominated by a massive black hole associated with Sgr A*.