doi.eso.org

• GRAVITY Collaboration
• Sturm, Eckhard [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Cao, Yixian [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Clenet, Yann [LESIA, Paris Observatory, Université PSL, Sorbonne University, Paris Cité University, CNRS, France]
• Davies, Ric [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Dexter, Jason [Max Planck Institut for Extraterrestrial Physics, Garching, Germany; JILA and Department of Astrophysical and Planetary Sciences, University of Colorado, USA]
• Eckart, Andreas [I. Physikalisches Institut, University of Cologne, Germany]
• Eisenhauer, Frank [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Genzel, Reinhard [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Gratadour, Damien [LESIA, Paris Observatory, Université PSL, Sorbonne University, Paris Cité University, CNRS, France]
• Hönig, Sebastian [Department of Physics and Astronomy, University of Southampton, UK]
• Kishimoto, Makoto [Department of Physics, Kyoto Sangyo University, Kita-ku, Japan]
• Lacour, Sylvestre [LESIA, Paris Observatory, Université PSL, Sorbonne University, Paris Cité University, CNRS, France]
• Lutz, Dieter [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Millour, Florentin [Lagrange Laboratory, Côte d’Azur Observatory, Côte d’Azur University, CNRS, Nice, France]
• Netzer, Hagai [School of Physics and Astronomy, Tel Aviv University, Israel]
• Perrin, Guy [LESIA, Paris Observatory, Université PSL, Sorbonne University, Paris Cité University, CNRS, France]
• Peterson, Brad [retired]
• Petrucci, Pierre-Olivier [Grenoble Alpes University, CNRS, IPAG, Grenoble, France]
• Pfuhl, Oliver [ESO; Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Prieto, M. Almudena [Astrophysics Institute of the Canaries, La Laguna, Tenerife, Spain]
• Rouan, Daniel [LESIA, Paris Observatory, Université PSL, Sorbonne University, Paris Cité University, CNRS, France]
• Santos, Daryl [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Shangguan, Jinyi [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Shimizu, Taro [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Stock, Matthias Raphael [Physics Department, Technical University of Munich, Germany]
• Waisberg, Idel [Max Planck Institut for Extraterrestrial Physics, Garching, Germany; Department of Particle Physics & Astrophysics, Weizmann Institute of Science, Rehovot, Israel]
• Woillez, Julien [European Southern Observatory (ESO)]
• de Zeeuw, Tim [Leiden Observatory, Leiden University, the Netherlands; Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Amorim, Antonio [Faculty of Sciences, University of Lisbon, Portugal]
• Brandner, Wolfgang [Max Planck Institute for Astronomy, Garching, Germany]
• Garcia, Paolo J. V. [CENTRA – Center for Astropysics and Gravitation, IST, University of Lisbon, Portugal]
• Gillessen, Stefan [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Förster Schreiber, Natascha M. [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Ott, Thomas [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Paumard, Thibaut [LESIA, Paris Observatory, Université PSL, Sorbonne University, Paris Cité University, CNRS, France]
• Perraut, Karine [Grenoble Alpes University, CNRS, IPAG, Grenoble, France]
• Straubmeier, Christian [I. Physikalisches Institut, University of Cologne, Germany]
• Tacconi, Linda. J. [Max Planck Institut for Extraterrestrial Physics, Garching, Germany]
• Sternberg, Amiel [School of Physics and Astronomy, Tel Aviv University, Israel]
• Tristram, Konrad R. W. [European Southern Observatory (ESO)]

Thanks to the superb sensitivity and resolution of GRAVITY, ESO’s near-infrared beam combiner for the Very Large Telescope Interferometer, our Large Programme study of the inner regions of active galactic nuclei (AGN) has delivered several recent breakthroughs. We have spatially resolved the broad line region (BLR) for three nearby AGN, supporting the rotating disc model, directly measuring the masses of their supermassive black holes (SMBHs), and testing the BLR radius-luminosity (R-L) scaling relation. We have measured the hot dust sizes for eight AGN and fully imaged the hot dust structure for two AGN. Our dust sizes also test the hot dust R-L scaling relation, revealing the first evidence for luminosity-dependent deviations from the expected relation. The novel GRAVITY data provide unique insight into the physics around SMBHs. In addition, they test the basic assumptions behind mass measurements based on the R-L scaling relation and reverberation mapping, which is currently the only method for measuring black hole masses in large surveys and out to high redshift. Our observations provide an entirely new, independent method for measuring SMBH masses. With GRAVITY+, we will be able to vastly expand to both larger samples and higher redshifts with the ultimate goal of tracing black hole growth and galaxy coevolution through cosmic time.