mariana trench
TRANSCRIPT
The Mariana Trench or Marianas Trench[1] is the deepest part of the world's oceans. It is
located in the western Pacific Ocean, to the east of the Mariana Islands. The trench is about
2,550 kilometres (1,580 mi) long but has an average width of only 69 kilometres (43 mi). It
reaches a maximum-known depth of 10.911 km (10,911 ± 40 m) or 6.831 mi (36,069 ±
131 ft) at the Challenger Deep, a small slot-shaped valley in its floor, at its southern
end,[2] although some unrepeated measurements place the deepest portion at 11.03
kilometres (6.85 mi).[3]
At the bottom of the trench the water column above exerts a pressure of 1,086 bars
(15,750 psi), over 1000 times the standard atmospheric pressure at sea level. At this
pressure the density of water is increased by 4.96%, making 95 litres of water under the
pressure of the Challenger Deep contain the same mass as 100 litres at the surface. The
temperature at the bottom is 1 to 4 °C.[4]
The trench is not the part of the seafloor closest to the center of the Earth. This is because
the Earth is not a perfect sphere: its radius is about 25 kilometres (16 mi) less at the poles
than at the equator.[5] As a result, parts of the Arctic Ocean seabed are at least 13 kilometres
(8.1 mi) closer to the Earth's center than the Challenger Deep seafloor.
Xenophyophores have been found in the trench by Scripps Institution of
Oceanography researchers at a record depth of 10.6 km (6.6 mi) below the sea surface.[6] On
17 March 2013, researchers reported data that suggested microbial life forms thrive within
the trench.[7][8]
Contents
[hide]
1 Names
2 Geology
3 Measurements
o 3.1 Descents
o 3.2 Planned descents
4 Life
5 Possible nuclear waste disposal site
6 See also
7 Notes
8 External links
Names
The Mariana Trench is named for the nearby Mariana Islands (in turn named Las Marianas in
honor of Spanish Queen Mariana of Austria, widow of Philip IV of Spain). The islands are part
of the island arc that is formed on an over
for the islands), on the western side of the trench.
Geology
The Mariana Trench is part of the
the boundary between two tectonic plates
the Pacific Plate, is subducted
west. Crustal material at the western edge of the Pa
crust on earth (up to 170 million years old), and is therefore cooler and more dense; hence
its great height difference relative to the higher
deepest area at the plate bound
The movement of the Pacific and Mariana plates is also indirectly responsible for the
formation of the Mariana Islands
upper mantle due to release of water that is trapped in minerals of the subducted portion of
the Pacific Plate.
Measurements
The Pacific plate is subducted beneath the Mariana Plate, creating the Mariana trench, and
(further on) the arc of the Mariana islands, as water trapped in the plate is released and
explodes upward to form island volcanoes.
See also: Challenger Deep
The trench was first sounded during the
depth of 4,475 fathoms (8.184
Grossen Ozeans by Petermann, which showed a
sounding. In 1899USS Nero, a converted collier, recorded a depth of 5269
31,614 ft).[10]Challenger II surveyed the trench using
and vastly easier way to measure depth than the sounding equipment and drag lines used in
the original expedition. During this survey, the deepest par
when the Challenger II measured a depth of 5,960
at 11°19′N 142°15′E, known as the
that is formed on an over-riding plate, called the Mariana Plate (also named
for the islands), on the western side of the trench.
The Mariana Trench is part of the Izu-Bonin-Mariana subduction system that forms
tectonic plates. In this system, the western edge of one plate,
subducted (i.e., thrust) beneath the smaller Mariana Plate
west. Crustal material at the western edge of the Pacific Plate is some of the oldest oceanic
crust on earth (up to 170 million years old), and is therefore cooler and more dense; hence
its great height difference relative to the higher-riding (and younger) Mariana Plate. The
deepest area at the plate boundary is the Mariana Trench proper.
The movement of the Pacific and Mariana plates is also indirectly responsible for the
Mariana Islands. These volcanic islands are caused by flux melting
upper mantle due to release of water that is trapped in minerals of the subducted portion of
is subducted beneath the Mariana Plate, creating the Mariana trench, and
(further on) the arc of the Mariana islands, as water trapped in the plate is released and
explodes upward to form island volcanoes.
during the Challenger expedition in 1875, which recorded a
(8.184 km).[9] In 1877 a map was published called
by Petermann, which showed a Challenger Tief at the location of that
, a converted collier, recorded a depth of 5269
surveyed the trench using echo sounding, a much more precise
and vastly easier way to measure depth than the sounding equipment and drag lines used in
the original expedition. During this survey, the deepest part of the trench was recorded
measured a depth of 5,960 fathoms (10,900 m, 35,760
, known as theChallenger Deep.[11]
plate, called the Mariana Plate (also named
system that forms
. In this system, the western edge of one plate,
Mariana Plate that lies to the
cific Plate is some of the oldest oceanic
crust on earth (up to 170 million years old), and is therefore cooler and more dense; hence
riding (and younger) Mariana Plate. The
The movement of the Pacific and Mariana plates is also indirectly responsible for the
flux melting of the
upper mantle due to release of water that is trapped in minerals of the subducted portion of
is subducted beneath the Mariana Plate, creating the Mariana trench, and
(further on) the arc of the Mariana islands, as water trapped in the plate is released and
in 1875, which recorded a
Tiefenkarte des
at the location of that
fathoms (9,636 m,
, a much more precise
and vastly easier way to measure depth than the sounding equipment and drag lines used in
t of the trench was recorded
(10,900 m, 35,760 ft)
In 1957, the Soviet vessel Vityaz reported a depth of 11,034 m (36,201 ft), dubbed
the Mariana Hollow.[3]
In 1962, the surface ship M.V. Spencer F. Baird recorded a maximum depth of 10,915 m
(35,840 ft), using precision depth gauges.
In 1984, the Japanese survey vessel Takuyō (拓洋), collected data from the Mariana Trench
using a narrow, multi-beam echo sounder; it reported a maximum depth of 10,924 m, also
reported as 10,920 ± 10 metres.[12]
Remotely Operated Vehicle KAIKO reached the deepest area of Mariana trench and made
the deepest diving record of 10,911 m on March 24, 1995.[13]
During surveys carried out between 1997 and 2001, a spot was found along the Mariana
Trench that had depth similar to that of the Challenger Deep, possibly even deeper. It was
discovered while scientists from the Hawaii Institute of Geophysics and Planetology were
completing a survey around Guam; they used a sonar mapping system towed behind the
research ship to conduct the survey. This new spot was named the HMRG (Hawaii Mapping
Research Group) Deep, after the group of scientists who discovered it.[14]
On 1 June 2009 sonar mapping of the Challenger Deep by the Simrad EM120 sonar
multibeam bathymetry system for deep water (300–11,000 m) mapping aboard the RV Kilo
Moana (mothership of the Nereus vehicle), has indicated a spot with a depth of 10,971 m
(35,994 ft). The sonar system uses phase and amplitude bottom detection, with an accuracy
of better than 0.2% of water depth across the entire swath (implying the depth figure is
accurate to less than ± 22 metres).[15][16]
In 2011, it was announced at the American Geophysical Union Fall Meeting that a US Navy
hydrographic ship equipped with a multibeam echosounder conducted a survey which
mapped the entire trench to 100 m resolution.[2] The mapping revealed the existence of four
rocky outcrops thought to be former seamounts.[17]
The Mariana Trench is a site chosen by researchers at Washington University and the Woods
Hole Oceanographic Institution in 2012 for a seismic survey to investigate the
subsurface water cycle. Using seismometers and hydrophones the scientists are able to map
structures as deep as 60 mi (97 km) beneath the surface.[18]
Descents
The Bathyscaphe Trieste (designed by
bottom of the Marianas Trench.
Four descents have been achieved. The first was the manned descent by Swiss
Italian-built, United States Navy
1:06 pm on 23 January 1960, with U.S. Navy Lieut
board.[11][20] Iron shot was used for
systems indicated a depth of 11,521 m (37,799
(35,814 ft).[21] The depth was estimated from a conversion of
calculations based on the water density
This was followed by the unmanned
expeditions directly measured very similar depths of 10,902 to 10,916 m.
The fourth was made by Canadian film director
reached the bottom of the Mariana Trench in the submersible vessel
Challenger.[22][23][24]
Planned descents
As of February 2012, at least three other teams are planning piloted submarines to reach the
bottom of the Mariana Trench. These include: Triton Submarines, a Florida based company
that designs and manufactures private submarines, for which a crew of three will take 120
minutes to reach the seabed;[25]
Group, designed by Graham Hawkes
take 140 minutes to reach the seabed;
based near San Francisco and set up in 1992, for which a crew of two or three will take 90
minutes to reach the seabed.[27]
Life
The expedition conducted in 1960 observed (with great surprise because of the high
pressure) at the bottom large living creatures such as a
long,[21] and a shrimp.[28] According to Piccard, "The bottom appeared light and clear, a
waste of firm diatomaceous ooze".
supposed sighting of the flatfish, and it is suggested that the creature may instead have been
a sea cucumber.[29][30]
During the second expedition, the unmanned vehicle Kaikō collected mud samples from
the seabed.[31] Tiny organisms were found to be living in those samples.
In July 2011 a research expedition deployed untethered landers, called dropcams, equipped
with digital video and lights to explore
living organisms, some gigantic single
centimeters), belonging to the class of
(designed by Auguste Piccard), the first manned vehicle to reach the
bottom of the Marianas Trench.[19]
Four descents have been achieved. The first was the manned descent by Swiss
United States Navy-owned bathyscaphe Trieste which reached the bottom at
pm on 23 January 1960, with U.S. Navy Lieutenant Don Walshand Jacques Piccard
Iron shot was used for ballast, with gasoline for buoyancy.[11]
systems indicated a depth of 11,521 m (37,799 ft), but this was later revised to 10,916 m
The depth was estimated from a conversion of pressure measured and
water density from sea surface to seabed.[20]
This was followed by the unmanned ROVs Kaikō in 1996 and Nereus in 2009. The first three
expeditions directly measured very similar depths of 10,902 to 10,916 m.
The fourth was made by Canadian film director James Cameron in 2012. On 26 March, he
reached the bottom of the Mariana Trench in the submersible vessel Deepsea
As of February 2012, at least three other teams are planning piloted submarines to reach the
bottom of the Mariana Trench. These include: Triton Submarines, a Florida based company
designs and manufactures private submarines, for which a crew of three will take 120 [25] Virgin Oceanic, sponsored by Richard Branson
Graham Hawkes, and piloted by Chris Welsh, for which the solo pilot will
take 140 minutes to reach the seabed;[26] and DOER Marine, a marine technology company,
based near San Francisco and set up in 1992, for which a crew of two or three will take 90 [27]
The expedition conducted in 1960 observed (with great surprise because of the high
pressure) at the bottom large living creatures such as a sole or flounder about 30
According to Piccard, "The bottom appeared light and clear, a
ooze".[21] Many marine biologists are now sceptical of the
sighting of the flatfish, and it is suggested that the creature may instead have been
During the second expedition, the unmanned vehicle Kaikō collected mud samples from
Tiny organisms were found to be living in those samples.
In July 2011 a research expedition deployed untethered landers, called dropcams, equipped
with digital video and lights to explore this region of the deep sea. Amongst many other
living organisms, some gigantic single-celled amoebas with a size of more than 4 inches (10
centimeters), belonging to the class ofxenophyophores were observed.[32]
), the first manned vehicle to reach the
Four descents have been achieved. The first was the manned descent by Swiss-designed,
which reached the bottom at
Jacques Piccard on
The onboard
sed to 10,916 m
measured and
in 2009. The first three
in 2012. On 26 March, he
Deepsea
As of February 2012, at least three other teams are planning piloted submarines to reach the
bottom of the Mariana Trench. These include: Triton Submarines, a Florida based company
designs and manufactures private submarines, for which a crew of three will take 120
Richard Branson's Virgin
, and piloted by Chris Welsh, for which the solo pilot will
, a marine technology company,
based near San Francisco and set up in 1992, for which a crew of two or three will take 90
The expedition conducted in 1960 observed (with great surprise because of the high
about 30 cm (1 ft)
According to Piccard, "The bottom appeared light and clear, a
Many marine biologists are now sceptical of the
sighting of the flatfish, and it is suggested that the creature may instead have been
During the second expedition, the unmanned vehicle Kaikō collected mud samples from
In July 2011 a research expedition deployed untethered landers, called dropcams, equipped
this region of the deep sea. Amongst many other
celled amoebas with a size of more than 4 inches (10 [32] Xenophyophores
are noteworthy for their size, their extreme abundance on the seafloor and their role as
hosts for a variety of organisms.
Possible nuclear waste disposal site
Like other oceanic trenches, the Mariana Trench has been proposed as a site for
waste disposal,[33][34] in the hope that tectonic plate
eventually push the nuclear waste deep into the
nuclear waste is prohibited by international law.
zones are associated with very large
unpredictable and possibly adverse to the safety of long
Trieste is a Swiss-designed, Italian
crew of two reached a record maximum depth of about 10,911 metres (35,797
deepest known part of the Earth
Trench near Guam in the Pacific
designer Auguste Piccard) and US Navy Lieutenant
Nekton.
Trieste was the first manned vessel to have reached the bottom of the Challenger Deep.
1 Design
2 The Mariana Trench dives
3 Other deep dives by Trieste
4 In art and literature
5 See also
6 References
7 Further reading
8 External links
Design[edit]
This section
improve this section by
material may be challenged and
are noteworthy for their size, their extreme abundance on the seafloor and their role as
hosts for a variety of organisms.
le nuclear waste disposal site
Like other oceanic trenches, the Mariana Trench has been proposed as a site for
in the hope that tectonic plate subduction occurring at the site might
eventually push the nuclear waste deep into the Earth's mantle. However, ocean dumping of
nuclear waste is prohibited by international law.[33][34][35] Furthermore, plate subduction
zones are associated with very large megathrust earthquakes, the effects of which are
unpredictable and possibly adverse to the safety of long-term disposal.[34]
Italian-built deep-diving research bathyscaphe
crew of two reached a record maximum depth of about 10,911 metres (35,797
Earth's oceans, the Challenger Deep, in the Mariana
Pacific. On 23 January 1960, Jacques Piccard(son of the boat's
) and US Navy Lieutenant Don Walsh achieved the goal of
was the first manned vessel to have reached the bottom of the Challenger Deep.
Contents
[hide]
This section does not cite any references or sources.
improve this section by adding citations to reliable sources
material may be challenged and removed. (January 2011)
are noteworthy for their size, their extreme abundance on the seafloor and their role as
Like other oceanic trenches, the Mariana Trench has been proposed as a site for nuclear
occurring at the site might
. However, ocean dumping of
Furthermore, plate subduction
, the effects of which are
bathyscaphe, which with her
crew of two reached a record maximum depth of about 10,911 metres (35,797 ft), in the
Mariana
(son of the boat's
achieved the goal of Project
was the first manned vessel to have reached the bottom of the Challenger Deep.
Please help
adding citations to reliable sources. Unsourced
(January 2011)
General arrangement drawing, showing the main features
Trieste consisted of a float chamber filled with
pressure sphere to hold the crew. This configuration (dubbed a
allowed for a free dive, rather than the previous
lowered to depth and raised from a ship by cable.
Trieste was designed by the Swiss scientist Auguste Piccard and originally built in Italy. His
pressure sphere, composed of two sections, was built by the company Acciaierie
upper part was manufactured by the company
Territory of Trieste (on the border between Italy and Yugoslavia); hence the name chosen for
the bathyscaphe. The installation of the pressure sphere was done in the Cantiere nav
di Castellammare di Stabia, near
the Mediterranean Sea near the
with the bathyscaphe FNRS-2.
of operation in the Mediterranean Sea, the
Navy in 1958 for $250,000.
At the time of Project Nekton, the
this was a series of floats filled with 85,000 litres (22,000
ballast tanks were included at either end of the vessel, as well as releasable iron ballast in
two conical hoppers along the bottom, fore and aft of the crew sphere. The crew occupied
the 2.16 m (7.09 ft) pressure sphere, attached to the underside of the float and accessed
from the deck of the vessel by a vertical shaft that penetrated the float and continued down
to the sphere hatch.
The pressure sphere provided just enough room for two people. It provided completely
independent life support, with a closed
modern spacecraft and spacesuits: oxygen was provided from pressure cylinders, and carbon
dioxide was scrubbed from breathing air by being passed through canisters of
Power was provided by batteries.
General arrangement drawing, showing the main features
consisted of a float chamber filled with gasoline(petrol) for buoyancy
pressure sphere to hold the crew. This configuration (dubbed a bathyscaphe
allowed for a free dive, rather than the previous bathysphere designs in which a sphere was
to depth and raised from a ship by cable.
was designed by the Swiss scientist Auguste Piccard and originally built in Italy. His
pressure sphere, composed of two sections, was built by the company Acciaierie
upper part was manufactured by the company Cantieri Riuniti dell'Adriatico
(on the border between Italy and Yugoslavia); hence the name chosen for
the bathyscaphe. The installation of the pressure sphere was done in the Cantiere nav
, near Naples.Trieste was launched on 26 August 1953 into
near the Isle of Capri. The design was based on previous experience
. Trieste was operated by the French Navy. After several years
of operation in the Mediterranean Sea, the Trieste was purchased by the United States
, the Trieste was more than 15 m (50 ft) long. The majority of
this was a series of floats filled with 85,000 litres (22,000 US gal) of gasoline, and water
ballast tanks were included at either end of the vessel, as well as releasable iron ballast in
along the bottom, fore and aft of the crew sphere. The crew occupied
ft) pressure sphere, attached to the underside of the float and accessed
from the deck of the vessel by a vertical shaft that penetrated the float and continued down
The pressure sphere provided just enough room for two people. It provided completely
independent life support, with a closed-circuit rebreather system similar to that u
modern spacecraft and spacesuits: oxygen was provided from pressure cylinders, and carbon
dioxide was scrubbed from breathing air by being passed through canisters of
Power was provided by batteries.
buoyancy, with a separate
bathyscapheby the Piccards),
designs in which a sphere was
was designed by the Swiss scientist Auguste Piccard and originally built in Italy. His
pressure sphere, composed of two sections, was built by the company Acciaierie Terni. The
Cantieri Riuniti dell'Adriatico, in the Free
(on the border between Italy and Yugoslavia); hence the name chosen for
the bathyscaphe. The installation of the pressure sphere was done in the Cantiere navale
was launched on 26 August 1953 into
. The design was based on previous experience
. After several years
United States
ft) long. The majority of
gal) of gasoline, and water
ballast tanks were included at either end of the vessel, as well as releasable iron ballast in
along the bottom, fore and aft of the crew sphere. The crew occupied
ft) pressure sphere, attached to the underside of the float and accessed
from the deck of the vessel by a vertical shaft that penetrated the float and continued down
The pressure sphere provided just enough room for two people. It provided completely
system similar to that used in
modern spacecraft and spacesuits: oxygen was provided from pressure cylinders, and carbon
dioxide was scrubbed from breathing air by being passed through canisters of soda-lime.
Don Walsh and Jacques Piccard aboard
The Trieste was subsequently fitted with a new pressure sphere, manufactured by
the Krupp Steel Works of Essen, Germany
ring and two caps).
To withstand the enormous pressure of 1.25
Challenger Deep, the sphere's walls were 12.7 centimetres (5.0
was overdesigned to withstand considerably more than the rated pressure). The sphere
weighed 13 metric tons in air and eight metric tons in water (giving it an average specific
gravity of 13/(13-8) = 2.6 times that of sea water). The float was necessary because of the
sphere's density: it was not possible to design a sphere large enough to hold a person that
could withstand the necessary pressures, yet also have metal walls thin
sphere to be neutrally buoyant. Gasoline was chosen as the float fluid because it is less
dense than water, incompressible even at extreme pressure, thus retaining its buoyant
properties and negating the need for thick, heavy walls for the f
Close-up of pressure sphere, with forward ballast silo at left
Don Walsh and Jacques Piccard aboard Trieste
was subsequently fitted with a new pressure sphere, manufactured by
Essen, Germany, in three finely-machined sections (an equatorial
To withstand the enormous pressure of 1.25 metric tons per cm² (110 MPa
Challenger Deep, the sphere's walls were 12.7 centimetres (5.0 in) thick (it
to withstand considerably more than the rated pressure). The sphere
in air and eight metric tons in water (giving it an average specific
8) = 2.6 times that of sea water). The float was necessary because of the
sphere's density: it was not possible to design a sphere large enough to hold a person that
could withstand the necessary pressures, yet also have metal walls thin enough for the
sphere to be neutrally buoyant. Gasoline was chosen as the float fluid because it is less
dense than water, incompressible even at extreme pressure, thus retaining its buoyant
properties and negating the need for thick, heavy walls for the float chamber.
up of pressure sphere, with forward ballast silo at left
was subsequently fitted with a new pressure sphere, manufactured by
machined sections (an equatorial
MPa) at the bottom of
in) thick (it
to withstand considerably more than the rated pressure). The sphere
in air and eight metric tons in water (giving it an average specific
8) = 2.6 times that of sea water). The float was necessary because of the
sphere's density: it was not possible to design a sphere large enough to hold a person that
enough for the
sphere to be neutrally buoyant. Gasoline was chosen as the float fluid because it is less
dense than water, incompressible even at extreme pressure, thus retaining its buoyant
loat chamber.
Observation of the sea outside the craft was conducted directly by eye, via a single, very
tapered, cone-shaped block of
identified which would withstand the external pressure. Outside illumination for the craft
was provided by quartz arc-light
atmospheres of pressure without any modification.
Nine tons of magnetic iron pellets were placed on the craft as
descent and allow ascent, since the extreme water pressures would not have permitted
compressed air ballast-expulsion tanks to be used at great depths. This additional weight
was held in place at the throats of two hopper
of an electrical failure the bathyscaphe would automatically rise to the surface.
Transported to the Naval Electronics Laboratory
modified extensively by the Americans, and then used in a series of deep
in the Pacific Ocean during the next few years, culminating in the dive to the bottom of the
Challenger Deep during January 1960.
23 January 1960: Trieste just before the record dive. The destroyer escort
background.
The Mariana Trench dives[edit
Trieste departed San Diego on 5 October 1959 for Guam aboard the freighter
participate in Project Nekton, a series of very deep dives in the Mariana Trench.
On 23 January 1960, she reached the ocean floor in the Challenger Deep (the deepest
southern part of the Mariana Trench), carrying Jacques Piccard and Don Walsh.
the first time a vessel, manned or unmanned, had reached the deepest known point of the
Earth's oceans. The onboard systems indicated a depth of 11,521 metres (37,799
although this was revised later to 10,916 metres (35,814
measurements have found Challenger Deep to be between 10,911 metres (35,797
10,994 metres (36,070 ft) deep.
The descent to the ocean floor took 4 hours 47 minutes at a des
second (3.0 ft/s).[3][4] After passing 9,000
panes cracked, shaking the entire vessel.
ocean floor, eating chocolate bars for sustenance. The temp
Observation of the sea outside the craft was conducted directly by eye, via a single, very
shaped block of acrylic glass (Plexiglas), the only transparent substance
identified which would withstand the external pressure. Outside illumination for the craft
lightbulbs, which proved to be able to withstand the over 1,000
atmospheres of pressure without any modification.
Nine tons of magnetic iron pellets were placed on the craft as ballast, both to speed the
descent and allow ascent, since the extreme water pressures would not have permitted
expulsion tanks to be used at great depths. This additional weight
was held in place at the throats of two hopper-like ballast silos by electromagnets, so in case
of an electrical failure the bathyscaphe would automatically rise to the surface.
lectronics Laboratory's facility in San Diego, California
modified extensively by the Americans, and then used in a series of deep-submergence tests
the Pacific Ocean during the next few years, culminating in the dive to the bottom of the
Challenger Deep during January 1960.
just before the record dive. The destroyer escortUSS
edit]
departed San Diego on 5 October 1959 for Guam aboard the freighter
, a series of very deep dives in the Mariana Trench.
1960, she reached the ocean floor in the Challenger Deep (the deepest
southern part of the Mariana Trench), carrying Jacques Piccard and Don Walsh.
a vessel, manned or unmanned, had reached the deepest known point of the
Earth's oceans. The onboard systems indicated a depth of 11,521 metres (37,799
although this was revised later to 10,916 metres (35,814 ft); fairly recently, more accurate
ements have found Challenger Deep to be between 10,911 metres (35,797
ft) deep.[2]
The descent to the ocean floor took 4 hours 47 minutes at a descent rate of 0.9 metres per
After passing 9,000 m (30,000 ft) one of the outer Plexiglas window
panes cracked, shaking the entire vessel.[5] The two men spent barely twenty minutes on the
ocean floor, eating chocolate bars for sustenance. The temperature in the cabin was 7°C
Observation of the sea outside the craft was conducted directly by eye, via a single, very
), the only transparent substance
identified which would withstand the external pressure. Outside illumination for the craft
bulbs, which proved to be able to withstand the over 1,000
ballast, both to speed the
descent and allow ascent, since the extreme water pressures would not have permitted
expulsion tanks to be used at great depths. This additional weight
llast silos by electromagnets, so in case
of an electrical failure the bathyscaphe would automatically rise to the surface.
San Diego, California, Trieste was
submergence tests
the Pacific Ocean during the next few years, culminating in the dive to the bottom of the
USS Lewis is in the
departed San Diego on 5 October 1959 for Guam aboard the freighter Santa Maria to
, a series of very deep dives in the Mariana Trench.
1960, she reached the ocean floor in the Challenger Deep (the deepest
southern part of the Mariana Trench), carrying Jacques Piccard and Don Walsh.[1] This was
a vessel, manned or unmanned, had reached the deepest known point of the
Earth's oceans. The onboard systems indicated a depth of 11,521 metres (37,799 ft),
ft); fairly recently, more accurate
ements have found Challenger Deep to be between 10,911 metres (35,797 ft) and
cent rate of 0.9 metres per
e outer Plexiglas window
The two men spent barely twenty minutes on the
erature in the cabin was 7°C
(45°F) at the time. While at maximum depth, Piccard and Walsh unexpectedly regained the
ability to communicate with the support ship, USS Wandank (ATA-204), using
a sonar/hydrophone voice communications system.[6] At a speed of almost a mile per second
(about five times the speed of sound in air), it took about seven seconds for a voice message
to travel from the craft to the support ship and another seven seconds for answers to return.
While at the bottom, Piccard and Walsh observed a number of
small sole and flounder.[7] Their claim the fish were swimming would prove at least some
vertebrate life can withstand the extreme pressure at the oceans' deepest point.[8] They
noted that the floor of the Challenger Deep consisted of "diatomaceous ooze". The ascent
took 3 hours 15 minutes.
Other deep dives by Trieste[edit]
Beginning in April 1963, Trieste was modified and used in the Atlantic Ocean to search for
the missing submarine USS Thresher (SSN-593). Trieste was delivered to Boston Harbor by
USS Point Defiance (LSD-31) under the command of Captain H. H. Haisten. In August
1963, Trieste found the wreck off the coast of New England, 8,400 ft (2,600 m) below the
surface.[9] Trieste was changed, improved and redesigned so many times that almost no
original parts remain. She was transported to the Washington Navy Yard where she was
exhibited along with the Krupp pressure sphere in the National Museum of the U.S. Navy at
the Washington Navy Yard in 1980. Her original Terni pressure sphere was incorporated into
the Trieste II.
In art and literature[edit]
The book "Ten Miles High, Two Miles Deep" (1957) (Whitlesey House, ISBN B0006AV2JW)
documents Picard's research on the stratosphere, as well as his work with the Trieste,
especially the design and construction.
The song 'The Trench' by Danish composer Ste van Holm is a tribute to the Mariana Trench
dives.
Voyage Of The Trieste - an instrumental track on The Chocolate Watchband's 1968 LP The
Inner Mystique.
The Trieste figures prominently in the 2008 novel The Extraordinary Event of Pia
H. by Canadian writer Nicola Vulpe.
The producers of the TV show Star Trek: The Next Generation named ship's captain Jean-Luc
Picard after Jacques Piccard.[10] They would later name one of the show's starships the U.S.S.
Trieste, after the bathyscaphe. She was noted for being small and slow.[11]
A bathyscaphe (/ˈbæθɨskeɪf/ or /ˈbæθɨskæf/) is a free-diving self-propelled deep-
sea submersible, consisting of a crew cabin similar to a bathysphere, but suspended below a
float rather than from a surface cable, as in the classic bathysphere design.[1]
The float is filled with gasoline because this is readily available, buoyant, and for
purposes, incompressible. The incompressibility of the gasoline means the tanks can be very
lightly constructed as the pressure inside and outside the tanks equalises and they are not
required to withstand any pressure differential at all. B
withstand a huge pressure differential and is massively built.
easily by replacing gasoline with water, which is denser.
Auguste Piccard, inventor of the first bathyscaphe, composed the name
the Ancient Greek words βαθύς
1 Mode of operation
2 History of development
3 Accomplishments
4 See also
5 References
6 External links
Mode of operation[edit]
To descend, a bathyscaphe floods air tanks with sea water, but unlike a
in the flooded tanks cannot be displaced with compressed air to ascend, because the water
pressures at the depths for which the craft was designed to operate are too great. For
example, the pressure at the bottom of the
a standard "H-type" compressed
released to ascend, the shot being lost to the ocean floor. The iron shot containers are in the
form of one or more hoppers which are open at the bottom throughou
shot being held in place by an electromagnet at the neck. This is a
requires no power to ascend; in fact, in the event of a power failure, shot
and ascent is automatic.
Internal arrangement of Trieste
History of development[edit]
The float is filled with gasoline because this is readily available, buoyant, and for
purposes, incompressible. The incompressibility of the gasoline means the tanks can be very
lightly constructed as the pressure inside and outside the tanks equalises and they are not
required to withstand any pressure differential at all. By contrast the crew cabin must
withstand a huge pressure differential and is massively built. Buoyancy can be trimmed
easily by replacing gasoline with water, which is denser.
, inventor of the first bathyscaphe, composed the name bathyscaphe
βαθύςbathys ("deep") and σκάφος skaphos ("vesse
Contents
[hide]
To descend, a bathyscaphe floods air tanks with sea water, but unlike a submarine
in the flooded tanks cannot be displaced with compressed air to ascend, because the water
pressures at the depths for which the craft was designed to operate are too great. For
example, the pressure at the bottom of the Challenger Deep is more than seven times that in
type" compressed gas cylinder. Instead, ballast in the form of
released to ascend, the shot being lost to the ocean floor. The iron shot containers are in the
form of one or more hoppers which are open at the bottom throughout the dive, the iron
shot being held in place by an electromagnet at the neck. This is a fail-safe
requires no power to ascend; in fact, in the event of a power failure, shot runs out by gravity
Trieste.
The float is filled with gasoline because this is readily available, buoyant, and for all practical
purposes, incompressible. The incompressibility of the gasoline means the tanks can be very
lightly constructed as the pressure inside and outside the tanks equalises and they are not
y contrast the crew cabin must
can be trimmed
bathyscaphe using
("vessel"/"ship").
submarine the water
in the flooded tanks cannot be displaced with compressed air to ascend, because the water
pressures at the depths for which the craft was designed to operate are too great. For
is more than seven times that in
ballast in the form of iron shot is
released to ascend, the shot being lost to the ocean floor. The iron shot containers are in the
t the dive, the iron
safe device as it
runs out by gravity
The first bathyscaphe was dubbed FNRS-2, named after the Fonds National de la Recherche
Scientifique, and built inBelgium from 1946 to 1948 by Auguste Piccard. (FNRS-1 had been
the balloon used for Piccard's ascent into the stratosphere in 1938). Propulsion was provided
by battery-driven electric motors.[1] The float held 10,000 gallons of aviation gasoline. There
was no access tunnel; the sphere had to be loaded and unloaded while on deck. The first
journeys were detailed in the Jacques Cousteau book The Silent World. As described in the
book, "the vessel had serenely endured the pressure of the depths, but had been destroyed
in a minor squall". FNRS-3 was a new submersible, using the crew sphere from the
damaged FNRS-2, and a new larger 20,000 gallon float.
Piccard's second bathyscaphe was actually a third vessel Trieste, which was purchased by
the United States Navy from Italy in 1957.[1] It had two water ballast tanks and eleven
buoyancy tanks holding 120,000 litres of gasoline.[2]
Accomplishments[edit]
In 1960 Trieste, carrying Piccard's son Jacques Piccard and Lt. Don Walsh, reached the
deepest known point on the Earth's surface, the Challenger Deep, in theMariana Trench.[1]
The onboard systems indicated a depth of 37,800 ft (11,521 m) but this was later corrected
to 35,813 ft (10,916 m) by taking into account variations arising from salinity and
temperature. Later and more accurate measurements made in 1995 have found the
Challenger Deep to be shallower at 35,798 ft (10,911 m).
The bathyscaphe was equipped with a powerful light, which illuminated a small flounder-like
fish, putting to rest the question of whether or not there was life at such a depth in the
complete absence of light. The crew of the Trieste noted that the floor consisted
of diatomaceous ooze and reported observing "some type of flatfish, resembling a sole,
about 1 foot long and 6 inches across" lying on the seabed.[3]
In 1995, the Japanese sent an unmanned submersible to this depth, Kaikō, but it was later
lost at sea. In 2009, a team from the Woods Hole Oceanographic Institution sent a robotic
submarine named Nereus to the bottom of the trench.[4]
On 25 March 2012, James Cameron reached the Challenger Deep in the Deepsea
Challenger submersible.[5][6][7]
A submarine is a watercraft capable of independent operation underwater. It differs from
a submersible, which has more limited underwater capability. The term most commonly
refers to a large, crewed, autonomous vessel. It is also sometimes used historically or
colloquially to refer to remotely operated vehicles and robots, as well as medium-sized or
smaller vessels, such as the midget submarine and the wet sub. Used as an adjective in
phrases such as submarine cable, "submarine" means "under the sea". The
noun submarine evolved as a shortened form of submarine boat (and is often further
shortened to sub).[1] For reasons of naval tradition, submarines are usually referred to as
"boats" rather than as "ships", regardless of their size.
Although experimental submarines had been built before, submarine design took off during
the 19th century, and they were adopted by several navies. Submarines were first widely
used during World War I (1914–1918), and now figure in many large navies. Military usage
includes attacking enemy surface ships (merchant and military), submarines, aircraft
carrier protection, blockade running, ballistic missile submarines as part of a nuclear strike
force, reconnaissance, conventional land attack (for example using a cruise missile), and
covert insertion of special forces. Civilian uses for submarines include marine science,
salvage, exploration and facility inspection/maintenance. Submarines can also be modified
to perform more specialized functions such as search-and-rescue missions or undersea
cable repair. Submarines are also used in tourism, and for undersea archaeology.
Most large submarines consist of a cylindrical body with hemispherical (and/or conical) ends
and a vertical structure, usually located amidships, which houses communications and
sensing devices as well as periscopes. In modern submarines, this structure is the "sail" in
American usage, and "fin" in European usage. A "conning tower" was a feature of earlier
designs: a separate pressure hull above the main body of the boat that allowed the use of
shorter periscopes. There is a propeller (or pump jet) at the rear, and various hydrodynamic
control fins. Smaller, deep diving and specialty submarines may deviate significantly from
this traditional layout. Submarines change the amount of water and air in their ballast
tanks to decrease buoyancy for submerging or increase it for surfacing.
Submarines have one of the widest ranges of types and capabilities of any vessel. They range
from small autonomous examples and one or two-person vessels that operate for a few
hours, to vessels that can remain submerged for six months—such as
the Russian Typhoon class, the biggest submarines ever built. Submarines can work at
greater depths than are survivable or practical for human divers.[2] Modern deep-diving
submarines derive from the bathyscaphe, which in turn evolved from the diving bell.