Nobody knows what happened to the world's greatest free-diver.

World champion deep sea diver feared dead.

Natalia Molchanova was the best female free-diver in the world.

For those who don’t know, free diving is a sport which involves plunging as deep as possible into the ocean without oxygen.

Molchanova has been crowned world champion 23 times and holds 40 world records.

At her best, Molchanova has dived a record of 71 metres without air, and can hold her breath for nine minutes.

Yet, over the weekend, it was announced Natalia Molchanova went missing during a deep sea dive.

On Sunday, 53-year-old Molchanova headed to the Balearic Sea in Spain for a leisurely 40 metre dive.

However, after diving into the sea that day — the champion never resurfaced.

Authorities fear she is most likely dead.

The New York Times described the currents in the Molchanova’s diving spot as “unpredictable and powerful”, and pose the possibility the Russian national was “swept away”.

The article also postures she may have blacked out, been attacked by a shark, or faced a cold snap in the water that shocked her system.

The truth is, there are several possible answers to Molchanova’s disappearance — and we won’t know what really happened until her body is found.

Three days later, the search party — comprised of private and Coast Guard boats, a helicopter and an underwater robot capable of searching the ocean up to 500m deep — is still trying to locate her body.

Meanwhile, tributes have poured in for the champion.

Will Trubridge, a 15-time free diving world record holder, sent his condolences to the Molchanova family.

The world has lost its greatest free diver,”he said. “I don’t think anybody would dispute that.”

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On top of her medals and records, Molchanova was previously a champion swimmer and could swim distances of 243 metres with flippers, or “fins” as the industry calls them.

She was an accomplished academic and held a PhD in pedagogical science.

Her possible death has shaken the diving world, but, as the President of the global governing body for freediving AIDA, told the New York Times: “we are playing with the ocea, and when you play with the ocean you know who is the strongest one.”

In a statement sharing the news of Molchanova’s disappearance, AIDA said she had a “passion for freediving that burned so deep inside of her that she dedicated her life to it.”

“Natalia is a proud mother of Oksana and Alexey. She loved children and was awaiting the day when she would become a Grandmother,” it said.

“She was an inspiration to all freedivers and despite being one of the fiercest competitors in the world, she was always calm and relaxed during competitions. She said ‘birth and death are important, but freediving competitions are just games for adults.'”

Do you have a news tip? Email us at news@mamamia.com.au. 

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