Here's who's on board the missing Titanic tourist sub

• A submersible carrying five tourists to the Titanic wreckage went missing in the ocean Sunday.
• The passengers include the submersible company's CEO, a UK space tourist, "Mr. Titanic," and a father and son.

A Titanic-touring submersible was carrying five people when it went missing in the ocean on Sunday.

The submersible, called Titan, lost communications with its mothership on Sunday as it carried the tourists down to the wreckage of the RMS Titanic. The voyage is operated by the company OceanGate.

Here's who is on board the missing sub.

Stockton Rush: The CEO of the Titanic tourism company

The OceanGate CEO, Stockton Rush, is one of the passengers on board the missing submersible, according to Reuters and CNN.

In a 2019 interview, Rush lamented "obscenely safe" diving security regulations. He held that line in a November 2022 episode of the "Unsung Science" podcast.

"At some point, safety just is pure waste," Rush told CBS journalist David Pogue for the podcast. "I think I can do this just as safely by breaking the rules."

According to his biography on OceanGate's website, Rush became the youngest pilot rated for jet transport in 1981, at age 19. He went on to obtain a bachelor's degree in Aerospace Engineering from Princeton University and an MBA from the UC Berkeley Haas School of Business, both institutions confirmed to Insider via email.

Rush told Pogue his greatest concern was obstacles that would prevent the sub from getting to the surface.

"Overhangs, fish nets, entanglement hazards," he said. "It's pretty clear — if it's an overhang, don't go under it. If there is a net, don't go near it. So, you can avoid those if you are just slow and steady."

Hamish Harding: A British adventurer who's been to space and the South Pole

Hamish Harding, 58, was adding the Titanic to his growing portfolio of daring expeditions.

Last year, he boarded Blue Origin's New Shepard rocket for a 10-minute flight to the edge of space, roaring through the skies to reach temporary weightlessness 66.5 miles above Earth. He has also completed two record-breaking missions to the South Pole, the first one featuring astronaut Buzz Aldrin.

Harding is also a pilot and holds at least four Guinness World Records, including the longest time spent navigating the Mariana Trench — the deepest part of the ocean — and a record for the fastest planet-circling flight crossing both poles, Insider previously reported.

Harding has been widely reported to be a billionaire, though his exact net worth is unknown, per Forbes. He is the chairman of Action Aviation, a Dubai-based aircraft sales firm.

Paul-Henry Nargeolet: A French diver known as "Mr. Titanic"

Paul-Henry Nargeolet, 77, has already visited the Titanic wreckage at least 35 times, Insider previously reported.

He was formerly a commander in the French navy, and was part of the first human expedition to visit the wreck site of the Titanic in 1987.

The first time he laid eyes on the Titanic wreckage, "it was absolutely unbelievable," Nargeolet told Forbes in 2012.

"Usually, on the submersibles, everyone is talking, there is always noise. But as we approached the bow, we all went silent," Nargeolet said at the time, adding, "There was absolutely no sound in the sub. I was in awe."

Nargeolet's spokesman told the BBC that the famed diver was one of the five passengers on the missing submersible.

Shahzada and Suleman Dawood: A father-son exploring duo

Shahzada Dawood, a 48-year-old British-Pakistani businessman, and his 19-year-old son, Suleman Dawood, are also on board the missing submersible.

The elder Dawood is vice chairman of the Dawood Hercules Corporation, which is part of the family business Dawood Group, according to a biography of the businessman on the website of the Search for Extraterrestrial Intelligence Institute (SETI), where he is on the board of trustees.

According to the bio, he is an "ardent animal lover" and lives in the UK with his wife, two children, dog, and cat.

"We are very grateful for the concern being shown by our colleagues and friends and would like to request everyone to pray for their safety," the Dawood family said in a statement to CBS News.