TRINITY SITE

by the U.S. Department of Energy

National Atomic Museum,
Albuquerque, New Mexico

Contents

THE FIRST ATOMIC TEST

On Monday morning July 16, 1945, the world was changed forever when the
first atomic bomb was tested in an isolated area of the New Mexico desert.
Conducted in the final month of World War II by the top-secret Manhattan
Engineer District, this test was code named Trinity. The Trinity test took
place on the Alamogordo Bombing and Gunnery Range, about 230 miles south
of the Manhattan Project’s headquarters at Los Alamos, New Mexico. Today
this 3,200 square mile range, partly located in the desolate Jornada del
Muerto Valley, is named the White Sands Missile Range and is actively used
for non-nuclear weapons testing.

Before the war the range was mostly public and private grazing land that
had always been sparsely populated. During the war it was even more lonely
and deserted because the ranchers had agreed to vacate their homes in
January 1942. They left because the War Department wanted the land to use
as an artillery and bombing practice area. In September 1944, a remote 18
by 24 square mile portion of the north-east corner of the Bombing Range
was set aside for the Manhattan Project and the Trinity test by the
military.

The selection of this remote location in the Jornada del Muerto Valley for
the Trinity test was from an initial list of eight possible test sites.
Besides the Jornada, three of the other seven sites were also located in
New Mexico: the Tularosa Basin near Alamogordo, the lava beds (now the El
Malpais National Monument) south of Grants, and an area southwest of Cuba
and north of Thoreau. Other possible sites not located in New Mexico were:
an Army training area north of Blythe, California, in the Mojave Desert;
San Nicolas Island (one of the Channel Islands) off the coast of Southern
California; and on Padre Island south of Corpus Christi, Texas, in the
Gulf of Mexico. The last choice for the test was in the beautiful San Luis
Valley of south-central Colorado, near today’s Great Sand Dunes National
Monument.

Based on a number of criteria that included availability, distance from
Los Alamos, good weather, few or no settlements, and that no Indian land
would be used, the choices for the test site were narrowed down to two in
the summer of 1944. First choice was the military training area in
southern California. The second choice, was the Jornada del Muerto Valley
in New Mexico. The final site selection was made in late August 1944 by
Major General Leslie R. Groves, the military head of the Manhattan
Project. When General Groves discovered that in order to use the
California location he would need the permission of its commander, General
George Patton, Groves quickly decided on the second choice, the Jornada
del Muerto. This was because General Groves did not want anything to do
with the flamboyant Patton, who Groves had once described as “the most
disagreeable man I had ever met.”1 Despite being second choice the
remote Jornada was a good location for the test, because it provided
isolation for secrecy and safety, was only 230 miles south of Los Alamos,
and was already under military control. Plus, the Jornada enjoyed
relatively good weather.

The history of the Jornada is in itself quite fascinating, since it was
given its name by the Spanish conquerors of New Mexico. The Jornada was a
short cut on the Camino Real, the King’s Highway that linked old Mexico to
Santa Fe, the capital of New Mexico. The Camino Real went north from
Mexico City till it joined the Rio Grande near present day El Paso, Texas.
Then the trail followed the river valley further north to a point where
the river curved to the west, and its valley narrowed and became
impassable for the supply wagons. To avoid this obstacle, the wagons took
the dubious detour north across the Jornada del Muerto. Sixty miles of
desert, very little water, and numerous hostile Apaches. Hence the name
Jornada del Muerto, which is often translated as the journey of death or
as the route of the dead man. It is also interesting to note that in the
late 16th century, the Spanish considered their province of New Mexico to
include most of North America west of the Mississippi!

The origin of the code name Trinity for the test site is also interesting,
but the true source is unknown. One popular account attributes the name to
J. Robert Oppenheimer, the scientific head of the Manhattan Project.
According to this version, the well read Oppenheimer based the name
Trinity on the fourteenth Holy Sonnet by John Donne, a 16th century
English poet and sermon writer. The sonnet started, “Batter my heart,
three-personed God.”2 Another version of the name’s
origin comes from University of New Mexico historian Ferenc M. Szasz. In
his 1984 book, The Day the Sun Rose Twice, Szasz quotes Robert W.
Henderson head of the Engineering Group in the Explosives Division of the
Manhattan Project. Henderson told Szasz that the name Trinity came from
Major W. A. (Lex) Stevens. According to Henderson, he and Stevens were at
the test site discussing the best way to haul Jumbo (see below) the thirty
miles from the closest railway siding to the test site. “A devout Roman
Catholic, Stevens observed that the railroad siding was called ‘Pope’s
Siding.’ He [then] remarked that the Pope had special access to the
Trinity, and that the scientists would need all the help they could get to
move the 214 ton Jumbo to its proper spot.”3

The Trinity test was originally set for July 4, 1945. However, final
preparations for the test, which included the assembly of the bomb’s
plutonium core, did not begin in earnest until Thursday, July 12. The
abandoned George McDonald ranch house located two miles south of the test
site served as the assembly point for the device’s core. After assembly,
the plutonium core was transported to Trinity Site to be inserted into the
thing or gadget as the atomic device was called. But, on the first attempt
to insert the core it stuck! After letting the temperatures of the core
and the gadget equalize, the core fit perfectly to the great relief of all
present. The completed device was raised to the top of a 100-foot steel
tower on Saturday, July 14. During this process workers piled up
mattresses beneath the gadget to cushion a possible fall. When the bomb
reached the top of the tower without mishap, installation of the explosive
detonators began. The 100-foot tower (a surplus Forest Service fire-watch
tower) was designated Point Zero. Ground Zero was at the base of the
tower.

As a result of all the anxiety surrounding the possibility of a failure of
the test, a verse by an unknown author circulated around Los Alamos. It
read:

A betting pool was also started by scientists at Los Alamos on the
possible yield of the Trinity test. Yields from 45,000 tons of TNT to zero
were selected by the various bettors. The Nobel Prize-winning (1938)
physicist Enrico Fermi was willing to bet anyone that the test would wipe
out all life on Earth, with special odds on the mere destruction of the
entire State of New Mexico!

Meanwhile back at the test site, technicians installed seismographic and
photographic equipment at varying distances from the tower. Other
instruments were set up for recording radioactivity, temperature, air
pressure, and similar data needed by the project scientists.

According to Lansing Lamont in his 1965 book Day of Trinity, life at
Trinity could at times be very exciting. One afternoon while scientists
were busily setting up test instruments in the desert, the tail gunner of
a low flying B-29 bomber spotted some grazing antelopes and opened up with
his twin.50-caliber machine guns. “A dozen scientists,… under the plane
and out of the gunner’s line of vision, dropped their instruments and
hugged the ground in terror as the bullets thudded about them.”5
Later a number of these scientists threatened to quit the project.

Workers built three observation points 5.68 miles (10,000 yards), north,
south, and west of Ground Zero. Code named Able, Baker, and Pittsburgh,
these heavily-built wooden bunkers were reinforced with concrete, and
covered with earth. The bunker designated Baker or South 10,000 served as
the control center for the test. This is where head scientist J. Robert
Oppenheimer would be for the test.

A fourth observation point was the test’s Base Camp, (the abandoned Dave
McDonald ranch) located about ten miles southwest of Ground Zero. The
primary observation point was on Compania Hill, located about 20 miles to
the northwest of Trinity near today’s Stallion Range Gate, off NM 380.

The test was originally scheduled for 4 a.m., Monday July 16, but was
postponed to 5:30 due to a severe thunderstorm that would have increased
the amount of radioactive fallout, and have interfered with the test
results. The rain finally stopped and at 5:29:45 a.m. Mountain War Time,
the device exploded successfully and the Atomic Age was born. The nuclear
blast created a flash of light brighter than a dozen suns. The light was
seen over the entire state of New Mexico and in parts of Arizona, Texas,
and Mexico. The resultant mushroom cloud rose to over 38,000 feet within
minutes, and the heat of the explosion was 10,000 times hotter than the
surface of the sun! At ten miles away, this heat was described as like
standing directly in front of a roaring fireplace. Every living thing
within a mile of the tower was obliterated. The power of the bomb was
estimated to be equal to 20,000 tons of TNT, or equivalent to the bomb
load of 2,000 B-29, Superfortresses!

After witnessing the awesome blast, Oppenheimer quoted a line from a
sacred Hindu text, the Bhagavad-Gita: He said: “I am become death, the
shatterer of worlds.”6 In Los Alamos 230 miles to the
north, a group of scientists’ wives who had stayed up all night for the
not so secret test, saw the light and heard the distant sound. One wife,
Jane Wilson, described it this way, “Then it came. The blinding light [no]
one had ever seen. The trees, illuminated, leaping out. The mountains
flashing into life. Later, the long slow rumble. Something had happened,
all right, for good or ill.”7

General Groves’ deputy commander, Brigadier General T. F. Farrell,
described the explosion in great detail: “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. It was
golden, purple, violet, gray, and blue. It lighted every peak, crevasse
and ridge of the nearby mountain range with a clarity and beauty that
cannot be described but must be seen to be imagined…”8

Immediately after the test a Sherman M-4 tank, equipped with its own air
supply, and lined with two inches of lead went out to explore the site.
The lead lining added 12 tons to the tank’s weight, but was necessary to
protect its occupants from the radiation levels at ground zero. The tank’s
passengers found that the 100-foot steel tower had virtually disappeared,
with only the metal and concrete stumps of its four legs remaining.
Surrounding ground zero was a crater almost 2,400 feet across and about
ten feet deep in places. Desert sand around the tower had been fused by
the intense heat of the blast into a jade colored glass. This atomic glass
was given the name Atomsite, but the name was later changed to Trinitite.

Due to the intense secrecy surrounding the test, no accurate information
of what happened was released to the public until after the second atomic
bomb had been dropped on Japan. However, many people in New Mexico were
well aware that something extraordinary had happened the morning of July
16, 1945. The blinding flash of light, followed by the shock wave had made
a vivid impression on people who lived within a radius of 160 miles of
ground zero. Windows were shattered 120 miles away in Silver City, and
residents of Albuquerque saw the bright light of the explosion on the
southern horizon and felt the tremor of the shock waves moments later.

The true story of the Trinity test first became known to the public on
August 6, 1945. This is when the world’s second nuclear bomb, nicknamed
Little Boy, exploded 1,850 feet over Hiroshima, Japan, destroying a large
portion of the city and killing an estimated 70,000 to 130,000 of its
inhabitants. Three days later on August 9, a third atomic bomb devastated
the city of Nagasaki and killed approximately 45,000 more Japanese. The
Nagasaki weapon was a plutonium bomb, similar to the Trinity device, and
it was nicknamed Fat Man. On Tuesday August 14, at 7 p.m. Eastern War
Time, President Truman made a brief formal announcement that Japan had
finally surrendered and World War II was over after almost six years and
60 million deaths!

On Sunday, September 9, 1945, Trinity Site was opened to the press for the
first time. This was mainly to dispel rumors of lingering high radiation
levels there, as well as in Hiroshima and Nagasaki. Led by General Groves
and Oppenheimer, this widely publicized visit made Trinity front page news
all over the country.

Trinity Site was later encircled with more than a mile of chain link
fencing and posted with signs warning of radioactivity. In the early 1950s
most of the remaining Trinitite in the crater was bulldozed into a
underground concrete bunker near Trinity. Also at this time the crater was
back filled with new soil. In 1963 the Trinitite was removed from the
bunker, packed into 55-gallon drums, and loaded into trucks belonging to
the Atomic Energy Commission (the successor of the Manhattan Project).
Trinity site remained off-limits to military and civilian personnel of the
range and closed to the public for many years, despite attempts
immediately after the war to turn Trinity into a national monument.

In 1953 about 700 people attended the first Trinity Site open house
sponsored by the Alamogordo Chamber of Commerce and the Missile Range. Two
years later, a small group from Tularosa, NM visited the site on the 10th
anniversary of the explosion to conduct a religious service and pray for
peace.

Regular visits have been made annually in recent years on the first
Saturday in October instead of the anniversary date of July 16, to avoid
the desert heat. Later Trinity Site was opened one additional day on the
first Saturday in April. The Site remains closed to the public except for
these two days, because it lies within the impact areas for missiles fired
into the northern part of the Range.

In 1965, Range officials erected a modest monument at Ground Zero. Built
of black lava rock, this monument serves as a permanent marker for the
site and as a reminder of the momentous event that occurred there. On the
monument is a plain metal plaque with this simple inscription: “Trinity
Site Where the World’s First Nuclear Device Was Exploded on July 16,
1945.”

During the annual tour in 1975, a second plaque was added below the first
by The National Park Service, designating Trinity Site a National Historic
Landmark. This plaque reads, “This site possesses national significance in
commemorating the history of the U.S.A.”

JUMBO

Lying next to the entrance of the chain link fence that still surrounds
Trinity Site are the rusty remains of Jumbo. Jumbo was the code name for
the 214-ton Thermos shaped steel and concrete container designed to hold
the precious plutonium core of the Trinity device in case of a nuclear
mis-fire. Built by the Babcock and Wilcox Company of Barberton, Ohio,
Jumbo was 28 feet long, 12 feet, 8 inches in diameter, and with steel
walls up to 16 inches thick.

The idea of using some kind of container for the Trinity device was based
on the fact that plutonium was extremely expensive and very difficult to
produce. So, much thought went into a way of containing the 15 lb.
plutonium core of the bomb, in case the 5,300 lbs. of conventional high
explosives surrounding the core exploded without setting off a nuclear
blast, and in the process scattering the costly plutonium (about 250
million dollars worth) across the dessert. After extensive research and
testing of other potential containment ideas, the concept of Jumbo was
decided on in the late summer of 1944.

However, by the spring of 1945, after Jumbo had already been built and
transported (with great difficulty) to the Trinity Site by the Eichleay
Corporation of Pittsburgh, it was decided not to explode the Trinity
device inside of Jumbo after all. There were several reasons for this new
decision: first, plutonium had become more readily (relatively) available;
second, the Project scientists decided that the Trinity device would
probably work as planned; and last, the scientists realized that if Jumbo
were used it would adversely affect the test results, and add 214 tons of
highly radioactive material to the atmosphere.

Not knowing what else to do with the massive 12 million dollar Jumbo, it
was decided to suspend it from a steel tower 800 yards from Ground Zero to
see how it would withstand the Trinity test. Jumbo survived the
approximately 20 kiloton Trinity blast undamaged, but its supporting
70-foot tall steel tower was flattened.

Two years later, in an attempt to destroy the unused Jumbo before it and
its 12 million dollar cost came to the attention of a congressional
investigating committee, Manhattan Project Director General Groves ordered
two junior officers from the Special Weapons Division at Sandia Army Base
in Albuquerque to test Jumbo. The Army officers placed eight 500-pound
conventional bombs in the bottom of Jumbo. Since the bombs were on the
bottom of Jumbo, and not the center (the correct position), the resultant
explosion blew both ends off Jumbo. Unable to totally destroy Jumbo, the
Army then buried it in the desert near Trinity Site. It was not until the
early 1970s that the impressive remains of Jumbo, still weighing over 180
tons, were moved to their present location.

SCHMIDT-McDONALD RANCH HOUSE

The Schmidt-McDonald ranch house is located two miles south of Ground
Zero. The property encompasses about three acres and consists of the main
house and assorted outbuildings. The house, surrounded by a low stone
wall, was built in 1913 by Franz Schmidt, a German immigrant and
homesteader. In the 1920s Schmidt sold the ranch to George McDonald and
moved to Florida.

The ranch house is a one-story, 1,750 square-foot adobe (mud bricks)
building. An ice house is located on the west side along with an 9′-4″
deep underground cistern. A 14 by 18.5 foot stone addition, which included
a modern bathroom, was added onto the north side in the 1930s. East of the
house there is a large, divided concrete water storage tank and a
windmill. South of the windmill are the remains of a bunkhouse, and a barn
which also served as a garage. Further to the east are corrals and holding
pens for livestock.

The McDonalds vacated their ranch house and their thousands of acres of
marginal range land in early 1942 when it became part of the Alamogordo
Bombing and Gunnery Range. The old house remained empty until Manhattan
Project personnel arrived in 1945. Then a spacious room in the northeast
corner of the house was selected by the Project personnel for the assembly
of the plutonium core of the Trinity device. Workmen installed work
benches, tables, and other equipment in this large room. To keep the
desert dust and sand out, the room’s windows and cracks were covered with
plastic and sealed with tape. The core of the bomb consisted of two
hemispheres of plutonium, (Pu-239), and an initiator. According to
reports, while scientists assembled the initiator and the Pu-239
hemispheres, jeeps were positioned outside with their engines running for
a quick getaway if needed. Detection devices were used to monitor
radiation levels in the room, and when fully assembled the core was warm
to the touch. The completed core was later transported the two miles to
Ground Zero, inserted into the bomb assembly, and raised to the top of the
tower.

The Trinity explosion on Monday morning, July 16, did not significantly
damage the McDonald house. Even though most of the windows were blown out,
and the chimney was blown over, the main structure survived intact. Years
of rain water dripping through holes in the metal roof did much more
damage to the mud brick walls than the bomb did. The nearby barn did not
fare as well. The Trinity test blew part of its roof off, and the roof has
since totally collapsed.

The ranch house stood empty and deteriorating for 37 years until 1982 when
the US Army stabilized it to prevent any further damage. The next year,
the Department of Energy and the Army provided funds for the National Park
Service to completely restore the house to the way it appeared in July,
1945. When the work was completed, the house with many photo displays on
Trinity was opened to the public for the first time in October 1984 during
the semi-annual tour. The Schmidt-McDonald ranch house is part of the
Trinity National Historic Landmark.

FOOTNOTES

1 (return)
[ Szasz, Ferenc. The Day the
Sun Rose Twice. Albuquerque: University of New Mexico Press, 1984. p. 28.]

2 (return)
[ Hayward, John, ed. John
Donne: Complete Poetry and Selected Prose. New York: Random House, Inc.,
1949. p. 285.]

3 (return)
[ Szasz, The Day the Sun Rose
Twice, p. 40.]

4 (return)
[ Wyden, Peter. Day One:
Before Hiroshima and After. New York: Simon and Schuster, 1984. p. 204.]

5 (return)
[ Lamont, Lansing. Day of
Trinity. New York: Atheneum, 1965. p. 123-124.]

6 (return)
[ Kunetka, James W. City of
Fire: Los Alamos and the Atomic Age, 1943-1945. Albuquerque: University of
New Mexico Press, 1978. p. 170.]

7 (return)
[ Wilson, Jane S. and
Charlotte Serber, eds. Standing By and Making Do: Women in Wartime Los
Alamos. Los Alamos: Los Alamos Historical Society, 1988. p. x, xi.]

8 (return)
[ Brown, Anthony Cave, and
Charles B. MacDonald. The Secret History of the Atomic Bomb. New York:
Dell, 1977. p. 516.]

BIBLIOGRAPHY

Bainbridge, Kenneth T. Trinity. Los Alamos: Los Alamos Scientific
Laboratory, (La-6300-H), 1946.

Brown, Anthony Cave, and Charles B. MacDonald. The Secret History of the
Atomic Bomb. New York: Dell, 1977.

Compton, Arthur Holly. Atomic Quest: A Personal Quest. New York: Oxford
University Press, 1956.

Fanton, Jonathan F., Stoff, Michael B. and Williams, R. Hal editors. The
Manhattan Project: A Documentary Introduction to the Atomic Age.
Philadelphia: Temple University Press, 1991.

Feis, Herbert. Japan Subdued: The Atomic Bomb and the End of the War in
the Pacific. Princeton: Princeton University Press, 1961.

Groves, Leslie R. Now it Can be Told: The Story of the Manhattan Project.
New York: Da Capo Press, 1975.

Hersey, John. Hiroshima. New York: Alfred A. Knopf, 1946.

Jette, Eleanor. Inside Box 1663. Los Alamos: Los Alamos Historical
Society, 1977.

Kunetka, James W. City of Fire: Los Alamos and the Atomic Age, 1943-1945.
Albuquerque; University of New Mexico Press, 1978.

Lamont, Lansing. Day of Trinity. New York: Athenaeum, 1965.

Rhodes, Richard. The Making of the Atomic Bomb. New York: Simon and
Schuster, 1986.

Skates, John Ray. The Invasion of Japan: Alternative to the Bomb.
Columbia; University of South Carolina Press, 1994.

Smyth, Henry DeWolf. Atomic Energy for Military Purposes. Princeton:
Princeton University Press, 1948.

Szasz, Ferenc. The Day the Sun Rose Twice. Albuquerque: University of New
Mexico Press, 1984.

Tibbets, Paul W. Flight of the Enola Gay. Reynoldsburg, Ohio: Buckeye
Aviation Book Company, 1989.

Williams, Robert C. Klaus Fuchs, Atom Spy. Cambridge, Massachusetts:
Harvard University Press, 1987.

Wilson, Jane S. and Serber, Charlotte, eds. Standing By and Making Do:
Women in Wartime Los Alamos. Los Alamos: Los Alamos Historical Society,
1988.

Wyden, Peter. Day One: Before Hiroshima and After. New York: Simon and
Schuster, 1984.

THE NATIONAL ATOMIC MUSEUM,

Kirtland Air Force Base, Albuquerque, New Mexico

Since its opening in 1969, the objective of the National Atomic museum has
been to provide a readily accessible repository of educational materials,
and information on the Atomic Age. In addition, the museum’s goal is to
preserve, interpret, and exhibit to the public memorabilia of this Age. In
late 1991 the museum was chartered by Congress as the United States’ only
official Atomic museum.

Prominently featured in the museum’s high bay is the story of the
Manhattan Engineer District, the unprecedented 2.2 billion dollar
scientific-engineering project that was centered in New Mexico during
World War II. The Manhattan Project as it was more commonly called,
developed, built, and tested the world’s first Atomic bomb in New Mexico.
This display also includes casings similar to the only Atomic bombs ever
used in warfare. Dropped on the Japanese cities of Hiroshima and Nagasaki,
these two bombs helped bring World War II to an end in mid-August 1945.
The story of the Manhattan Project’s three secret cities, Hanford,
Washington, Los Alamos, New Mexico, and Oak Ridge, Tennessee, is also
presented in this area.

A portion of the museum, the low bay, is devoted to exhibits on the
research, development, and use of various forms of nuclear energy.
Historical and other traveling exhibits are also displayed in this area.
Also found in the low bay is the museum’s store, which is operated by the
museum’s foundation.

Adjacent to the low bay is the theater. The featured film is David Wolpers
classic 1963 production, Ten Seconds That Shook The World. This excellent
film is a 53-minute documentary on the Manhattan Project. Other films
relating to the history of the Atomic Age are available for viewing and
checkout from the library.

Next to the theater is the library/Department of Energy public reading
room, containing government documents that are available to the public for
in-library research. The library also has many nuclear related books
available for reference and checkout.

Located around the outside of the museum are a number of large exhibits.
These include the Boeing B-52B jet bomber that dropped the United States’
last air burst H-bomb in 1962, and a 280-mm (11 inches) Atomic cannon,
once America’s most powerful field artillery. Also found in this area is a
Navy TA-7C (a modified A-7B) Corsair II fighter-bomber, a veteran of the
Vietnam War. Many other nuclear weapons systems, rockets, and missiles are
found in this area.

In front of the museum are a pair of Navy Terrier missiles. The Terrier
was the Navy’s first operational surface to air missile. To the south of
the museum, next to the visitors parking lot, is a Republic F-105D
Thunderchief fighter-bomber. Further south is a World War II Boeing B-29
Superfortress. This plane is similar to the B-29’s, Enola Gay and Bockscar
that dropped the Atomic bombs on Japan.

The National Atomic Museum, is open 9 a.m. to 5 p.m. daily, except for New
Years Day, Easter, Thanksgiving, and Christmas. The museum is located at
20358 Wyoming Blvd. SE, on Kirtland Air Force Base, Albuquerque, New
Mexico. Guided tours for groups are available by calling (505)845-4636 in
advance. Admission and tours are free, and cameras are always welcome!