By JOHN MARKOFFSEPT
An
international team of archaeologists plans to return this month to the site of an ancient shipwreck off a Greek
island. This time, they will have the aid of an advanced diving suit that
will give them much more time to probe for new artifacts.
Alexandros Sotiriou, a diver,
during an Exosuit training dive in Massachusetts.
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Part robot and
part submarine, the lightweight suit, called the Exosuit, is intended to allow
a diver to work for long periods at depths of more than 1,000 feet, avoiding
time-consuming decompression periods. The suit provides a diver with freedom of
movement because of a propulsion system and from an unusual set of rotating
joints developed by Phil Nuytten, an explorer and diving technology specialist.
Evocative of
the “Iron Man” movies and their hero, Tony Stark, the aluminum-alloy suit
allows the operator to sit on a bicycle-type seat. It is connected to the
surface by a high-speed fiber-optic network that relays high-definition video,
and it has robotic grippers that will allow divers to manipulate artifacts
found at the site.
The Exosuit has
a self-contained life-support system designed to allow divers to work as long
as two and a half days without surfacing, though at first, the shifts will be
much shorter. Its rotary joints are extremely resilient; the smallest, at the
wrist, can withstand up to six tons of pressure on a small surface area, Mr.
Nuytten said.
“You feel like
you are in a segmented suit of armor,” said Brendan P. Foley, an archaeologist
at Woods
Hole Oceanographic Institution in Massachusetts and a director of the shipwreck
project who tested the suit this summer. “It’s funny — I was imagining I
was going to feel like Tony Stark, but I felt a lot like Lancelot.”
Nuytco
(pronounced NEWT-co), a company founded by Mr. Nuytten, has made similar
atmospheric diving suits for rescue operations for many of the world’s navies.
The suits are virtually weightless underwater, and a version developed for the
United States Office
of Naval Research will allow divers to swim with flippers for long periods
at great depths.
The shipwreck,
off the island of Antikythera, was discovered by Greek divers in 1900. A Roman
vessel that is believed to have sunk during the first century B.C., it held the
renowned Antikythera Mechanism, a mechanical device for
predicting celestial movement, along with luxury goods like pottery and bronze
statues.
Since the
original discovery, the Antikythera wreck was explored only once — by Jacques
Cousteau for several weeks in 1976 — until the fall of 2012, when a team of
divers from Woods Hole and a Greek government agency, the Hellenic Ephorate of
Underwater Antiquities, began a more systematic exploration of the waters
around the island.
The site also
holds a second shipwreck, and there is some historical evidence that the two
vessels were traveling together, perhaps carrying material from the conquests
of the Roman general Lucius Cornelius Sulla to be displayed in victory parades
in Rome.
Records from
the original dive indicate that one marble statue was dropped during efforts to
recover it. It is also possible that some objects that were moved from the shipwreck
and mistaken for boulders are also artifacts.
But the project
is as much about experimenting with new diving technology as it is about field
archaeology, said David A. Mindell, an engineering professor at the
Massachusetts Institute of Technology who has specialized in marine systems.
“Brendan is
really the only one who is doing what he is doing, especially in the deeper
waters,” he said of Dr. Foley. “That stuff is basically land archaeology
translated to scuba gear.”
This is the
third year the divers will operate at the site. On each expedition, they have
added advanced technologies.
Previously,
they used closed-circuit rebreathers — devices that scrub carbon dioxide from
exhaled breath, allowing the diver to inhale it again — and diver propulsion
vehicles equipped with high-resolution cameras.
A fragment of the Antikythera
Mechanism
at the National Archaeological Museum in Athens.
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On this year’s
expedition, they will also use several underwater robots, including an
autonomous vehicle called the Iver, which will be operated by scientists from
the Australian Centre for Marine Robotics. That will make it possible to create
a 3D map of the shipwreck sites.
Dr. Foley said
he hoped the Exosuit would be used for up to three dives each day during the
monthlong expedition, with each dive lasting two to three hours. A small group
of divers will share the Exosuit, with others using equipment that requires
decompression.
Theotokis Theodoulou, an
archaeologist, before
a training dive in the Exosuit at Woods Hole
Oceanographic Institution in Massachusetts.
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Although the
Antikythera Mechanism was recovered at the beginning of the last century, it wasn’t
until 1974 that scientists began to unravel the mystery of its design. Although
it has been described as a primitive computer, it is not programmable, and
Michael T. Wright, a British historian who has reconstructed the mechanism, has
said he considers it to be an elaborate planetarium.
Only about half
of the original mechanism has been recovered, and the researchers are hoping to
find the remaining portion.
Archaeologists
believe it was not a unique device. Indeed, according to Dr. Foley, there are historical
references to other kinds of mechanisms in early manuscripts.
“This is the
kind of thing that quite literally wakes me up in the middle of the night,” he
said. “I can’t sleep because I’m so excited.”
nytimes.com