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基于图象的信息隐藏的C源码

Trinity Site: 1945-1995.
  A National Historic Landmark
  White Sands Missile Range, New Mexico




Contents:

 Radiation at Trinity Site.
 How to Get to Trinity Site.
 Trinity Site National Historic Landmark.
 The Manhattan Project.
 The Theory.
 Building a test site.
 Jumbo.
 Bomb Assembly.
 The test.
 After the explosion.
 It's the Schmidt house.
 Afterwards.
 White Sands Missile Range.
 Reading List.


 
"The effects could well be called unprecedented, magnificent,
beautiful, stupendous, and terrifying.  No man-made phenomenon of such
tremendous power had ever occurred before.  The lighting effects
beggared description.  The whole country was lighted by a searing
light with the intensity many times that of the midday sun."

Brig. Gen. Thomas Farrell



Radiation at Trinity Site


In deciding whether to visit ground zero at Trinity Site, the
following information may prove helpful to you.

Radiation levels in the fenced, ground zero area are low.  On an
average the levels are only 10 times greater than the region's natural
background radiation.  A one-hour visit to the inner fenced area will
result in a whole body exposure of one-half to one milliroentgen.

To put this in perspective, a U.S. adult receives an average exposure
of 90 milliroentgens every year from natural and medical sources.  For
instance, the Department of Energy says we receive between 35 and 50
milliroentgens every year from the sun and from 20 to 35
milliroentgens every year from our food.  Living in a brick house adds
50 milliroentgens of exposure every year compared to living in a frame
house.  Finally, flying coast to coast in a jet airliner gives an
exposure of between three and five milliroentgens on each trip.

Although radiation levels are low, some feel any extra exposure should
be avoided.  The decision is yours.  It should be noted that small
children and pregnant women are potentially more at risk than the rest
of the population and are generally considered groups who should only
receive exposure in conjunction with medical diagnosis and treatment.
Again, the choice is yours.

At ground zero, Trinitite, the green, glassy substance found in the
area, is still radioactive and must not be picked up.


Typical radiation exposures for Americans
 Per The National Council on Radiation Protection

On hour at ground zero = 1/2 mrem

Cosmic rays from space = 40 mrem at sea level per year

Radioactive minerals in rocks and soil = 55 mrems per year

Radioactivity from air, water, and food = anywhere from 20 to 400 mrem
per year

About 22 mrem per chest X-ray and 900 mrem for whole-mouth dental X-
rays

Smoking one pack of cigarettes a day for one year = 40 mrem

Miscellaneous such as watch dials and smoke detectors = 2 mrem per
year



How to Get to Trinity Site


Trinity Site, where the world's first atomic bomb was exploded in
1945, is normally open to the public twice a year--on the first
Saturday in April and October.

Trinity is located on the northern end of the 3,200-square-mile White
Sands Missile Range, N.M., between the towns of Carrizozo and Socorro,
N.M.  There are two ways of entering the restricted missile range on
tour days.

Visitors can enter through the range's Stallion Range Center which is
five miles south of Highway 380.  The turnoff is 12 miles east of San
Antonio, N.M. , and 53 miles west of Carrizozo, N.M.  The Stallion
gate will be open 8 a.m. to 2 p.m.  Visitors arriving at the gate
between those hours will receive handouts and will be allowed to drive
unescorted the 17 miles to Trinity Site.  The road is paved and
marked.

The other way of entering the missile range is by travelling with a
caravan sponsored by the Alamogordo (N.M.) Chamber of Commerce.  The
caravan forms at the Otero County Fairgrounds in Alamogordo and leaves
at 8 a.m.  Visitors entering this way will travel as an escorted group
with military police to and from Trinity Site.  The drive is 170 miles
round trip.  There are no service station facilities on the missile
range.  The caravan is scheduled to leave Trinity Site at 12:30 p.m.
for the return to Alamogordo.  The caravan may leave later if there is
a large number of vehicles in the returning caravan.

In 1995, an additional open house will be conducted on July 16, the
50th anniversary of the Trinity test.  Visitors may enter the missile
range through the Stallion Range Center gate from 5 to 11 a.m.  There
will be no caravan leaving from Alamogordo, N.M., for this event.  The
early hours will allow visitors to be on-site at 5:29:45 a.m., the
time the Trinity Site detonation occurred, and should help visitors
avoid the 100-plus degree afternoon temperatures common here in July.

Included on the Trinity Site tour is Ground Zero where the atomic bomb
was placed on a 100-foot steel tower and exploded on July 16, 1945.  A
small monument now marks the spot.  Visitors also see the McDonald
ranch house where the world's first plutonium core for a bomb was
assembled.  The missile range provides historical photographs and a
Fat Man bomb casing for display.  There are no ceremonies or speakers.

Portable toilet facilities are available on site.  Hot dogs and sodas
are sold at the parking lot.  Cameras are allowed at Trinity Site, but
their use is strictly prohibited anywhere else on White Sands Missile
Range.

For more information, contact the White Sands Missile Range Public
Affairs Office at [phone]/1700.



Trinity Site National Historic Landmark


Trinity Site is where the first atomic bomb was tested at 5:29:45 a.m.
Mountain War Time on July 16, 1945.  The 19 kiloton explosion not only
led to a quick end to the war in the Pacific but also ushered the
world into the atomic age.  All life on Earth has been touched by the
event which took place here.

The 51,500-acre area was declared a national historic landmark in
1975.  The landmark includes base camp, where the scientists and
support group lived; ground zero, where the bomb was placed for the
explosion; and the McDonald ranch house, where the plutonium core to
the bomb was assembled.  On your visit to Trinity Site you will be
able to see ground zero and the McDonald ranch house.  In addition, on
your drive into the Trinity Site area you will pass one of the old
instrumentation bunkers which is beside the road just west of ground
zero.



The Manhattan Project


The story of Trinity Site begins with the formation of the Manhattan
Project in June 1942.  The project was given overall responsibility of
designing and building an atomic bomb.  At the time it was a race to
beat the Germans who, according to intelligence reports, were building
their own atomic bomb.

Under the Manhattan Project three large facilities were constructed.
At Oak Ridge, Tenn., huge gas diffusion and electromagnetic process
plants were built to separate uranium 235 from its more common form,
uranium 238.  Hanford, Wash. became the home for nuclear reactors
which produced a new element called plutonium.  Both uranium 235 and
plutonium are fissionable and can be used to produce an atomic
explosion.

Los Alamos was established in northern New Mexico to design and build
the bomb.  At Los Alamos many of the greatest scientific minds of the
day labored over the theory and actual construction of the device.
The group was led by Dr. J. Robert Oppenheimer who is credited with
being the driving force behind building a workable bomb by the end of
the war.



The Theory


Los Alamos scientists devised two designs for an atomic bomb--one
using the uranium and another using the plutonium.  The uranium bomb
was a simple design and scientists were confident it would work
without testing.  The plutonium bomb worked by compressing the
plutonium into a critical mass which sustains a chain reaction.  The
compression of the plutonium ball was to be accomplished by
surrounding it with lens-shaped charges of conventional explosives.
They were designed to all explode at the same instant.  The force is
directed inward, thus smashing the plutonium from all sides.

In an atomic explosion, a chain reaction picks up speed as atoms
split, releasing neutrons plus great amounts of energy.  The escaping
neutrons strike and split more atoms, thus releasing still more
neutrons and energy.  In a nuclear explosion this all occurs in a
millionth of a second with billions of atoms being split.

Project leaders decided a test of the plutonium bomb was essential
before it could be used as a weapon of war.  From a list of eight
sites in California, Texas, New Mexico and Colorado, Trinity Site was
chosen as the test site.  The area already was controlled by the
government because it was part of the Alamogordo Bombing and Gunnery
Range which was established in 1942.  The secluded Jornado del Muerto
was perfect as it provided isolation for secrecy and safety, but was
still close to Los Alamos.



Building a test site


In the fall of 1944 soldiers started arriving at Trinity Site to
prepare for the test.  Marvin Davis and his military police unit
arrived from Los Alamos at the site on Dec. 30, 1944.  The unit set up
security checkpoints around the area and had plans to use horses to
ride patrol.  According to Davis the distances were too great and they
resorted to jeeps and trucks for transportation.  The horses were
sometimes used for polo, however.  Davis said that Capt. Bush, base
camp commander, somehow got the soldiers real polo equipment to play
with but they preferred brooms and a soccer ball.

Other recreation at the site included volleyball and hunting.  Davis
said Capt. Bush allowed the soldiers with experience to use the Army
rifles to hunt deer and pronghorn.  The meat was then cooked up in the
mess hall.  Leftovers went into soups which Davis said were excellent.

Of course, some of the soldiers were from cities and unfamiliar with
being outdoors a lot.  Davis said he went to relieve a guard at the
Mockingbird Gap post and the soldier told Davis he was surprised by
the number of "crawdads" in the area considering it was so dry.  Davis
gave the young man a quick lesson on scorpions and warned him not to
touch.

Throughout 1945 other personnel arrived at Trinity Site to help
prepare for the test.  Carl Rudder was inducted into the Army on Jan.
26, 1945.  He said he passed through four camps, took basic for two
days and arrived at Trinity Site on Feb. 17.  On arriving he was put
in charge of what he called the "East Jesus and Socorro Light and
Water Company." It was a one-man operation--himself.  He was
responsible for maintaining generators, wells, pumps and doing the
power line work.

A friend of Rudder's, Loren Bourg, had a similar experience.  He was a
fireman in civil life and ended up trained as a fireman for the Army.
He worked as the station sergeant at Los Alamos before being sent to
Trinity Site in April 1945.  In a letter Bourg said, "I was sent down
here to take over the fire prevention and fire department.  Upon
arrival I found I was the fire department, period."

As the soldiers at Trinity Site settled in they became familiar with
Socorro.  They tried to use the water out of the ranch wells but found
it so alkaline they couldn't drink it.  In fact, they used Navy salt-
water soap for bathing.  They hauled drinking water from the fire
house in Socorro.  Gasoline and diesel was purchased from the Standard
bulk plant in Socorro.

According to Davis, they established a post office box, number 632, in
Socorro so getting their mail was more convenient.  The trips into
town also offered them the chance to get their hair cut in a real
barbershop.  If they didn't use the shop, Sgt. Greyshock used horse
clippers to trim their hair.



Jumbo


The bomb design to be used at Trinity Site actually involved two
explosions.  First there would be a conventional explosion involving
the TNT and then, a fraction of a second later, the nuclear explosion,
if a chain reaction was maintained.  The scientists were sure the TNT
would explode, but were initially unsure of the plutonium.  If the
chain reaction failed to occur, the TNT would blow the very rare and
dangerous plutonium all over the countryside.

Because of this possibility, Jumbo was designed and built.  Originally
it was 25 feet long, 10 feet in diameter and weighed 214 tons.
Scientists were planning to put the bomb in this huge steel jug
because it could contain the TNT explosion if the chain reaction
failed to materialize.  This would prevent the plutonium from being
lost.  If the explosion occurred as planned, Jumbo would be vaporized.

Jumbo was brought to Pope, N.M., by rail and unloaded.  A specially
built trailer with 64 wheels was used to move Jumbo the 25 miles to
Trinity Site.

As confidence in the plutonium bomb design grew it was decided not to
use Jumbo.  Instead, it was placed in a steel tower about 800 yards
from ground zero.  The blast destroyed the tower, but Jumbo survived
intact.

Today Jumbo rests at the entrance to ground zero so all can see it.
The ends are missing because, in 1946, the Army detonated eight 500-
pound bombs inside it.  Because Jumbo was standing on end, the bombs
were stacked in the bottom and the asymmetry of the explosion blew the
ends off.

To calibrate the instruments which would be measuring the atomic
explosion and to practice a countdown, the Manhattan scientists ran a
simulated blast on May 7.  They stacked 100 tons of TNT onto a 20-foot
wooden platform just southeast of ground zero.  Louis Hemplemann