An open association of Institutes and Laboratories willing to collaborate in the exploitation and development of long baseline interferometry.

The European Interferometry Initiative (Eii) is an open association of Institutes and Laboratories willing to collaborate in the exploitation and development of optical long baseline interferometry in optical/infrared astronomy. The Eii confederates the activities included in the European Commission instruments of the 6th, 7th and H2020 R&D program, including the most recent Optical/RadioNet Pilot Program. The current Eii activities are:

  • The establishment of a network of VLTI expertise centres across Europe
  • A joint research activity preparing for the third generation of VLTI instruments
  • The Fizeau staff exchange programme
  • The organisation of VLTI training summer schools and VLTI open days

Funding for the activities was obtained through the OPTICON/RadioNet Pilot Program (2021-2024; grant agreement 101004719), OPTICON - the Optical Infrared Co-ordination Network for astronomy - Horizon 2020 (2017-2020, grant agreement 730890), OPTICON FP7 II (2013-2016, grant agreement 312430), OPTICON FP7 (2009-2012, grant agreement 226604), ONTHEFRINGE (2006-2008: grant MSCF-CT-2005-029954) and OPTICON FP6 (2002-2006, RII3-Ct-2004-001566).

The MoU and Management composition can be found here.


This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 101004719. This material reflects only the authors views and the Commission is not liable for any use that may be made of the information contained therein.



OPTICON/RadioNet Pilot Program

Under H2020-INFRAIA-2018-2020, the European Commission approved the project OPTICON/RadioNet Pilot (ORP), which mobilizes the two flagship communities of advanced radio and optical/infrared astronomy.

12th VLTI Summer School

The 12th VLTI Interferometry School will be held online on the week of September 16-19, 2024 and in Porquerolles, Provence (France) on the week of September 22-28, 2024. Pre-registration is now closed.

EII Early Career Prize

To promote excellence, the Eii is happy to invite nominations (March 1-April 15) for the Eii Early Career Prize. The prize will be awarded every 2 years by the Eii Scentific Council to a young scientist distinguished in optical/IR interferometry.

ERIS 2024

The 10th European Radio Interferometry School (ERIS2024) will take place at the Instituto de Astrofísica de Andalucía (IAA-CSIC), in Granada (Spain) from the 30th of September to the 4th of October 2024.The deadline for registration is Friday May 10.

NEON 2024

The 2024 NEON Observing School will be held at the National Observatory of Athens (Greece) from the 13th to the 25th of October 2024. The deadline for applications is Friday May 31.

ORP School on Multi-Messenger Astrophysics

The ORP School on Multi-messenger Astrophysics will be hosted by the Durham University (UK) from the 2nd to the 6th of September 2024. The application deadline is Friday June 14.