The ability of the near future second generation VLTI instrument GRAVITY to
constrain the properties of the Galactic center black hole is investigated. The
Galactic center infrared flares are used as probes of strong-field gravity,
within the framework of the hot spot model according to which the flares are
the signature of a blob of gas orbiting close to the black hole's innermost
stable circular orbit. Full general relativistic computations are performed,
together with realistic observed data simulations, that lead to conclude that
GRAVITY could be able to constrain the black hole's inclination parameter.Comment: 5 pages, 3 figures, to appear in the Proceedings of the French
Society of Astronomy and Astrophysics (SF2A