On this page, we list the main changes that affected MATISSE and this web site.

Period 106: MATISSE is offered in both service and visitor mode on all the standard ATs and UTs configurations. Following succesfull commissioning, MATISSE is offered for the first time in P106 with GRAVITY as a fringe tracker (GRA4MAT mode). Among the possible spectral resolution available with the GRA4MAT mode, we also include for the very first time the HIGH+ spectral resolution in L and M-band. Please note: the turbulence categories for the GRA4MAT and for MATISSE stand-alone mode are different. The execution time of GRA4MAT concatenations is different from the one of MATISSE stand-alone. The details of the mode, and the limiting magnitudes are provided in the Instrument Description page. 

February 2020: open call for GRA4MAT mode Science verification. Deadline February 24th.

January 2020: a new version of the User and the Template Manuals have been released. They can be found in the Manual section from the menu on the left. The User and Template Manual, as well as the MATISSE webpages, are essential to prepare the phase 2 of the observations.

Period 105: during P105 MATISSE is offered in both service and visitor mode on all the standard ATs and UTs configurations. The following changes apply with respect to the previous call for proposal; the details are listed in the Instrument Description page.

  • The L-band limiting magnitudes have been updated, and the M-band medium and low resolution are now offered after succesfull commissioning. 
  • Due to additional commissioning scheduled during P105, that may lead to a revision of the instrument performances in M-band, the M-band medium resolution is not offered for monitoring programs.
  • The medium resolution L- and M-band modes, as well as the high resolution L-band are offered for specific spectral windows centered around spectral features of interest. Additional set-ups are available in visitor mode. The spectral windows available in service mode are listed in the Instrument Description page.

Following the introduction of the new phase 1 proposal preparation and submission tool, the following important changes apply to all the VLTI instruments.

  • A new atmospheric turbulence constraint replaces the current seeing constraint.
  • The way the requested VLTI baselines and VLTI observation types have to be specified has changed. From P105 on, alternative baseline configuration can be specified at P1 in a keyword list, in order of priority. Note that each run will be scheduled on one configuration. Most likely, it will be the first (primary) choice. However, a run may exceptionally be scheduled on an alternative choice if the primary choice of the baseline configuration cannot be scheduled. All set-ups of each run need to specify exactly the same baseline configuration. If different configurations are needed, different runs need to be specified, each with one configuration.

August 2018: The decision to offer MATISSE in ESO period 103 was made.  MATISSE will be offered for both service and visitor mode observing.  Due to the still ongoing commissioning, that may lead to revision of instrument capabilities and performances,MATISSE will not be offered for Large Programmes or Monitoring Programmes in P103.

MATISSE in the news

For the latest highlighted science results, please consult the ESO Press Release page.


  • ESO Press Release #1808 (5 March 2018) MATISSE Instrument Sees First Light on ESO's Very Large Telescope Interferometer