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Tests of gravity theories using observations of the Galactic Center and the center of the galaxy M87. Advances in astronomy in 2019 It is now generally accepted that there is a supermassive black hole at the Galactic Center, however one should support this hypothesis or choose an alternative model with two observational techniques namely (a) monitoring the orbits of bright stars near the Galactic Center using the largest telescopes, (b) measuring the size and shape of shadows around the black hole, giving an alternative opportunity to estimate the parameters of the black hole using the Event Horizon Telescope. A few years ago, the LIGO-Virgo collaboration not only detected gravitational waves and binary black holes, but also found the upper limit of the graviton mass $m_g < 1.2 \times 10^{-22}$~eV (Abbott et al. 2016). In paper \cite{Zakharov_16} it is shown that the observations of the largest telescopes Keck and VLT (GRAVITY) motion of the bright star S2 in the vicinity of the Galactic Center allow with comparable accuracy to limit the mass of the graviton, namely, at the level of $m_g < 2.9 \times 10^{-21}$~eV. Further studies by Zakharov et al. (2018) showed that accurate observations of the trajectories of bright stars can improve the current estimate of the graviton mass obtained from the analysis of the gravitational-wave signal of the LIGO--Virgo collaboration. Currently, these predictions are confirmed by the results of GRAVITY observations of the group working on the largest European telescopes in Chile, and our approach to estimate the parameters of alternative theories of gravity is used in processing the latest observations of the motions of bright stars with the VLT (GRAVITY) and Keck groups. In 2019 estimates of graviton mass done in paper by Zakharov et al. (2016) along with the LIGO--Virgo collaboration estimates are included in the section that provides estimates of graviton mass in the Particle Data Group Review, which collects quantities whose knowledge is important in particle physics (Tanabashi et al. 2018). Analysis of the size of shadows around a supermassive black hole at the galactic center (or/and at the center of M87) observed with the Event Horizon Telescope also limits the parameters of various alternative theories of gravity (Zakharov, 2019). In regard to a recent decision of the Breakthrough Prize committee to award the Event Horizon Telescope team and the Nobel Committee's decision to award J. Peebles (for his results in physical cosmology) and M. Mayor and D. Queloz for the discovery of the first exoplanet near a solar type star, we discuss their works and works of other people which are related to results. One can say that 10 years after UNESCO's celebration of the year of astronomy, 2019 may also be recognized as a very successful year for astronomy and astrophysics. References Abbott, B. P. et al.: Phys. Rev. Lett. 2016. V. 116. 061102. Zakharov, A. F., Jovanovic, P., Borka, D., Borka Jovanovic, V., J. Astropart. Phys. (JCAP) 05 (2016) 045. Zakharov, A. F., Jovanovi\'c P., Borka D. \& Borka Jovanovi\'c, V.// J. Cosm. Astropart. Phys. (JCAP) 04 (2018) 050. Tanabashi M. et al. (Particle Data Group), // Phys. Rev. D 2018, 030001 and 2019 update. Zakharov, A. F., Intern. J. Mod. Phys. D. 2019. V. 28, 1941003.