down because we’d come that far and I had a good shot,” he said.
Their mission fully mapped the South Sandwich Trench in high
resolution for the first time. And that data showed Meteor Deep,
previously labeled the bottommost point, actually wasn’t in the
right place. The real nadir was some 30 kilometers away. Other car-
tographic discoveries included a second depression, and massive
underwater mountains nearly 1,500 meters high, as lofty at Mount
Pinatubo. (Vescovo and the mission crew will get to name them.)
From there, Pressure Drop headed to the other side of the planet,
passing around South Africa’s Cape Horn. In early April, Vescovo
dived the Java Trench, touching down 7,192 meters under the Indian
Ocean—another first. Then Lahey did a research dive so chief sci-
entist Jamieson could finally descend into his area of specialty, the
hadal zone, for the first time in his career.
There, Limiting Factor’s cameras caught a new species of snailfish,
and, in Jamieson’s words, “an extraordinary gelatinous animal.” He
thinks it’s something called a stalked ascidian, or sea squirt, and you
can see it for yourself on YouTube.
Jamieson often chafes at how the public reacts to discoveries like
this. Animals of the deep, he says, “are only ever wheeled out as a Vic-
torian freak show. The Pacific’s half the planet, but as soon you show
an animal from down below, it’s
like: ‘It’s weird! It’s alien!’ It’s not
alien. They cover more of the
planet than humans do. If any-
one’s the alien, it’s the human.”
Creatures that live in hadal
zones, in total darkness and at
almost unfathomable pressure,
fill a vital role in our earthly
ecosystem. Jamieson offers the
example of holothurians, com-
monly known as sea cucumbers,
as a species that does more for
Earth than rhinos or giraffes
or lions. “There are billions of
them all around the planet, con-
stantly irrigating the seafloor,
keeping it oxygenated.” But they
don’t look good in a zoo.
We probably react the way we
do because it’s all so unfamiliar.
Operating in the deep is a big
investment, and traditionally
the military has been disinter-
ested in the depths. Fear is a
factor too, albeit an irrational
one, if you ask expedition leader
McCallum. “When we look at
space, we don’t think of the dan-
ger,” he said. “But when we look
into the ocean, we immediately
think about the risk of drown-
ing. They both have dangers that have to be managed.
I think diving is probably safer.”
McCallum believes we’re entering a new era of
exploration in the deep. He says another company is
developing a second full-ocean-depth sub, though any
specifics, including the firm’s name, are still secret. In
the meantime, he’s already heard from individuals who
are interested in purchasing Limiting Factor. He also
thinks there’s an immediate market for a touring com-
pany to offer rides down to Challenger Deep: “I imagine
there are people in the world who might spend a million
dollars to be among the first 10 people to do that.”n May 13, 2019, the team made its biggest an-
nouncement yet. On his first dive in the Mariana
Trench—the fourth of his five deeps—Vescovo
set a new record. He reached 10,928 meters: at
least 12 meters beyond Don Walsh and Jacques
Piccard’s original achievement in 1960. (Despite fanfare,
James Cameron’s dive was slightly shallower.)Ship of Tools
Pressure Drop is Five
Deeps’ roving base, toting
the sub around the globe.58 FALL 2019 • POPSCI.COM
COURTESYFIVEDEEPSEXPEDITION