Natalia Molchanova, 53, the world's greatest free diver, took a chartered boat off the coast of Ibiza on Sunday, went diving, and never resurfaced. After more than two days of searching, the New York Times reports Molchanova is not expected to be found alive.

Free diving is different than scuba diving because divers hold their breath instead of using any kind of equipment to breath. A post on the diver's official Facebook page explains Molchanova was separated from the friends she went diving with while they were out in 30 to 40 meters (about 130 feet) of water.

In 2013, Molchanova was the first woman to ever cross the 100-meter diving barrier at a world championship diving contest in Kalamata, Greece. She has broken 41 other world records and is a 23-time world champion in free diving, according to CNN. She could hold her breath for nine minutes at a time at these depths.

The Times reports that the water temperature in Ibiza where Molchanova was diving was about 79 degrees, though farther below the surface it drops to 65. Such a big difference in temperatures could potentially "shock a diver's system," but unless Molchanova's body is found, it is impossible to say what actually happened to her. 

Molchanova's son Alexey, who is also a free diver, told the Times he believes his mother is gone. "It seems she'll stay in the sea," he said. "I think she would like that."

Update 8/6, 12:54 p.m.: According to ESPN, Spain's maritime rescue services have halted their search for Molchanova after almost four days of searching. Her family plans to continue searching underwater in the area by using a remote-controlled robot.

According to the New York Times, Molchanova was giving a private diving lesson to two people. She dropped a line about 65 feet down (which is normal for beginner-level free divers) and was supposed to escort her students down each time they took a dive. Molchanova's son believes his mother may have taken a deeper dive on her own while her students were resting.

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Tess Koman
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Tess Koman covers breaking (food) news, opinion pieces, and features on larger happenings in the food world. She oversees editorial content on Delish. Her work has appeared on Cosmopolitan.com, Elle.com, and Esquire.com.