Henri-Paul Nargeolet, who was nicknamed “Mr Titanic”, was one of five people onboard the Titan tourist sub when it lost contact with the surface after plunging down to visit the wreck in mid-June.

An attempted rescue operation in the North Atlantic briefly captivated the world before it found evidence that the vessel had imploded underwater, killing all on board.

The Titanic exhibition which opened in the French capital was “largely the result of the work, ingenuity and passion of Henri-Paul Nargeolet,” the event’s producer Pascal Bernardin said.

Nargeolet, 77, had been expected to attend the exhibition’s opening.

The explorer helped bring up many of the 260 objects on display – which include navigation instruments and hooks from the ship as well as watches and jewellery from its passengers – from the wreck.

The exhibition, which runs from July 18th to September 10th at the Porte de Versailles exhibition centre, starts off with a more than four-metre-long model of the mythic ship.

Visitors are then taken on a journey from the night the Titanic departed England for New York in April 1912, through the sinking of what was the world’s largest cruise ship after its hull was ruptured by an iceberg.

The exhibition features recreations of the ship’s cabins, grand staircase and even the oppressive atmosphere of its engine room.

A joint French-American expedition discovered the Titanic’s wreck nearly four kilometres underwater off the coast of Newfoundland in 1985.

Nargeolet directed or participated in six of the eight exploration missions to the wreck between 1987 and 2010, which brought back more than 5,000 objects to the surface.

The vessels used for those missions were quite different to the Titan.

Previously voiced concerns about the sub’s safety came to light after its implosion.

Titan’s US-based operator OceanGate, whose CEO Stockton Rush was among those killed onboard Titan, has suspended all its activities indefinitely.

It had charged $250,000 a seat on the submersible, which was about the size of an SUV car.

The US Coast Guard and Canadian authorities have launched probes into the cause of the tragedy.

Titanic l’Exposition runs at Porte de Versaille expo centre in eastern Paris from July 18th to September 10th. Tickets start at €24 – full details here