GRAVITY and the VLTI have transformed optical interferometry with groundbreaking results on the Galactic Center, active galactic nuclei, and exoplanets.

The GRAVITY+ project will upgrade GRAVITY and the VLTI in order to open up the extragalactic sky for milliarcsecond-resolution interferometric imaging, and give access to targets as faint as K = 22 mag. GRAVITY+ will measure the black hole masses of active galactic nuclei across cosmic time, and obtain high-quality exoplanet spectra and orbits.

GRAVITY+ will provide wide-field off-axis fringe tracking, and improved sensitivity and contrast from new natural guide star and laser guide star adaptive optics for all VLT 8 m unit telescopes. The GRAVITY+ upgrades can start immediately, and can be implemented incrementally, keeping the impact on operation to a minimum. They will add new, globally unique science capabilities with every step. As an infrastructure upgrade of the VLTI, GRAVITY+ will serve all present and future VLTI instruments along with their communities.

Following a summer 2020 recommendation by ESO’s STC, GRAVITY+ is entering a Phase A process in order to become ESO’s next VLT facility instrument. GRAVITY+ will be built by a consortium including MPE, INSU/CNRS, University of Cologne, MPIA, CENTRA, and University of Southampton, in close collaboration with ESO.

This picture shows the upgrade of GRAVITY and the VLTI to GRAVITY+ for faint-science, all-sky, high-contrast, milliarcsecond interferometric imaging. The key elements are improved instrument throughput and vibration control, wide-field off-axis fringe tracking, state-of-the-art adaptive optics, and laser guide stars for all telescopes.

Science cases for GRAVITY+ include:

  • The Galactic Center
  • Galaxy AGN coevolution and the masses of supermassive Black Holes, including super-Eddington accretion, tidal disruption events, and supermassive Black Hole binaries
  • Characterization of exoplanets
  • Young suns and their planet-forming disks
  • Microlenses
  • Massive stars
  • Intermediate-mass black holes

More information on the GRAVITY+ concept and science can be found in this document, which is based on the GRAVITY+ proposal to ESO.

Upcoming Events

Go to Editor View