Institute for Advanced Study / Princeton University Joint Astrophysics Colloquium

The GRAVITY experiment at the Very Large Telescope Interferometer (VLTI) has fundamentally redefined the landscape of high-angular-resolution astronomy. By delivering routine milli-arcsecond imaging, a thousandfold increase in sensitivity, and micro-arcsecond astrometry, it has pushed the boundaries of the field. The recent GRAVITY+ upgrade featuring laser guide star adaptive optics further expands its sky coverage and sensitivity by orders of magnitude. While initially focused on key programs like the Galactic Center, GRAVITY and the VLTI now serve a broad range of research, including exoplanets, star and planet formation, stellar physics, compact objects, and extragalactic astrophysics out to cosmological distances. This presentation gives an overview of the key results, with special focus on the Galactic Center and supermassive black holes, discusses existing limitations, and outlines future developments.