KM3NeT - Deployment

Welcome, ORCA-42!

8 July 2026 – A very successful sea operation took place during last week-end, leading to a new extension of the ORCA submarine telescope off the coast of Toulon, France.

During the operation, four new detection units were installed in the deep sea and connected to the detector in a record time of an average 8.5 hours of operation per unit.

Ancillary actions were also performed, including a deep-sea inspection of some detection units, recovery of one acoustic emitter of the positioning system which requires some maintenance and recovery of biofouling traps installed years ago which will provide new insights on how to preserve the transparency of the glass of the optical modules in the deep sea over very extended periods.

At the end of the operation, the apparatus comprises 42 detection units.

As usual, the operation was performed with two ships: the Castor 02 of Foselev, for deployment of the detection units, and the Janus II of SAAS (formerly Comex), equipped with the Apache deep-sea remotely operated vehicle (ROV), for submarine operations.

Many thanks to the crews offshore as well as to the team who performed the functional tests of the new detection units from the shore station and anyone else involved in making this great step forward possible!

Welcome, ORCA42!

Sonar map of the deep-sea installations at ORCA at the end of the operation, comprising two nodes for submarine connections (marked N1 and N2), a calibration base (CB) connected to an instrumentation unit (IU), and a total of 42 detection units (DUs) – those installed during the latest campaign are marked.


Three more detection units for KM3NeT/ORCA

1 May 2023 – During a two days sea operation, 27-28 April 2023, three detection units were successfully connected to the ORCA detector of KM3NeT in a record time of just over 24 hours. In addition, an acoustic beacon was recovered for battery replacement. The total number of deployed ORCA units is now 18, as visible in the sonar scan above.

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Liveblog about the ongoing sea operation for ARCA

10 September 2021 – In the evening of September 10, five new detection units of KM3NeT, onboard the Handin Tide, will sail from Malta headed to the KM3NeT/ARCA detection site. This site is located 80 km off the coast of Capo Passero, Sicily (Italy). During a 1-week operation, the detection units will be deployed and connected to the ARCA neutrino telescope at 3,500 m depth, adding up to the six already in operation.

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Handin Tide left the harbour of Malta

10 September 2021 – the Handin Tide left the port of Malta around 5 p.m. CEST.

The navigation to the KM3NeT site is estimated to take about 10 hours.

The weather forecast is good. The activity on site will start early morning tomorrow.

Keep following the  ARCA-blog.



ORCA is operational

8 March 2019 – Last month, the KM3NeT team of CPPM, Marseille together with the ship crews successfully installed an ORCA detection unit. It was the first unit connected to the refurbished main electro-optical cable to shore. After a few weeks of technology tests, the unit is given free for physics runs. ORCA is operational! Read more