Humans Aren’t Meant to Explore the Depths of the Ocean. They Still Insist on Doing It and Asking a Question: How Deep Can a Submarine Go?

Lt. Isaac Peral boarded the world’s first electrically powered submarine on Sep. 8, 1888 in the Bay of Cadiz, Spain. However, at that time, humankind had already been trying for two centuries to develop an effective method of exploring the ocean’s depths.

For decades, every time a new device went underwater, scientists wondered how deep it would go, its limitations, and whether it would come back safe and sound. Nearly a century later, the questions remain the same (though there are some answers).

Submarines can reach great depths under extreme pressure, but do we know their limits?

What’s the deepest a human being has ever gone in the ocean? According to the latest measurements, the Mariana Trench in the Pacific Ocean is about 6,856 miles below the surface. The truth is that humankind hasn’t been able to reach that depth.

On Jan. 23, 1960, U.S. Navy Lt. Don Walsh and famed Swiss oceanographer Jacques Piccard used a specially designed bathyscaphe (the Trieste) to reach the 6,782-mile depth of the Challenger Deep, southeast of Guam, after a journey of more than four hours.

It almost cost them their lives, but it was the record to beat for years—and other explorers have broken it many times. Caladan Oceanic founder Victor Vescovo holds the current record: 6,788 miles, reached in April 2019.

However, ‘regular’ submarines cannot reach these depths. It’s unnecessary. German media outlet t-online reports that today’s naval submarines typically go about 0.3 miles deep. Certain types of nuclear submarines easily reach 0.55 miles. In fact, in recent years, they’ve gone much deeper, according to an English translation provided by Google.

Nevertheless, the oceans remain a great unknown. Experts often say that humans know more about the surfaces of Mars, Venus, and Mercury compared to the ocean floor. Despite their best efforts, explorers have only mapped roughly one-fifth of the ocean floor and aren’t progressing much.

And that’s strange because the ocean is becoming increasingly important. There are dozens of things for which knowledge of the seafloor is critical, such as ocean circulation, tidal dynamics, and tsunami prediction. Experts need this information to locate our marine food supply, transport sediment, and map underwater geohazards. It’s also important when it comes to the installation of submarine cables, pipelines, and the extraction of minerals, oil, and gas. And let’s not forget about infrastructure development, construction, and maintenance.

Despite all of this, and even though it’s 2024, we still don’t know much about the seafloor.

Image | Darren Halstead (Unsplash)

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