Project Mogul (sometimes referred to as Operation Mogul) was a
top secret project by the
US Army Air Forces involving microphones flown on
high-altitude balloon
High-altitude balloons are crewed or uncrewed balloons, usually filled with helium or hydrogen, that are released into the stratosphere, generally attaining between above sea level. In 2002, a balloon named BU60-1 reached a record altitude of .
...
s, whose primary purpose was long-distance detection of
sound waves generated by
Soviet
The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...
atomic bomb tests. The project was carried out from 1947 until early 1949. It was a classified portion of an unclassified project by
New York University
New York University (NYU) is a private research university in New York City. Chartered in 1831 by the New York State Legislature, NYU was founded by a group of New Yorkers led by then- Secretary of the Treasury Albert Gallatin.
In 1832, th ...
(NYU) atmospheric researchers. The project was moderately successful, but was very expensive and was superseded by a network of
seismic detectors and air sampling for fallout, which were cheaper, more reliable, and easier to deploy and operate.
Project Mogul was conceived by
Maurice Ewing who had earlier researched the
deep sound channel in the oceans and theorized that a similar sound channel existed in the
upper atmosphere Upper atmosphere is a collective term that refers to various layers of the atmosphere of the Earth above the troposphere and corresponding regions of the atmospheres of other planets, and includes:
* The mesosphere, which on Earth lies between th ...
: a certain height where the air pressure and temperature result in minimal speed of sound, so that sound waves would propagate and stay in that channel due to
refraction
In physics, refraction is the redirection of a wave as it passes from one medium to another. The redirection can be caused by the wave's change in speed or by a change in the medium. Refraction of light is the most commonly observed phenomen ...
. The project involved arrays of balloons carrying disc microphones and radio transmitters to relay the signals to the ground. It was supervised by James Peoples, who was assisted by
Albert P. Crary.
One of the requirements of the balloons was that they maintain a relatively
constant altitude over a prolonged period of time. Thus instrumentation had to be developed to maintain such constant altitudes, such as pressure sensors controlling the release of
ballast.
The early Mogul balloons consisted of large clusters of rubber
meteorological balloons, however, these were quickly replaced by enormous balloons made of
polyethylene
Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging ( plastic bags, plastic films, geomembranes and containers including b ...
plastic. These were more durable, leaked less
helium
Helium (from el, ἥλιος, helios, lit=sun) is a chemical element with the symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic ta ...
, and also were better at maintaining a constant altitude than the early rubber balloons. Constant-altitude-control and polyethylene balloons were the two major innovations of Project Mogul.
Subsequent programs
Project Mogul was the forerunner of the
Skyhook balloon
Skyhook balloons were high-altitude balloons developed by Otto C. Winzen and General Mills, Inc. They were used by the United States Navy Office of Naval Research (ONR) in the late 1940s and 1950s for atmospheric research, especially for const ...
program, which started in the late 1940s, as well as two other
espionage
Espionage, spying, or intelligence gathering is the act of obtaining secret or confidential information ( intelligence) from non-disclosed sources or divulging of the same without the permission of the holder of the information for a tang ...
programs involving balloon overflights and photographic surveillance of the Soviet Union during the 1950s,
Project Moby Dick and
Project Genetrix
Project Genetrix, also known as WS-119L, was a United States Air Force program designed to launch General Mills manufactured surveillance balloons over Communist China, Eastern Europe and the Soviet Union to take aerial photographs and collect ...
. The spy balloon overflights raised storms of protest from the Soviets. The constant-altitude balloons also were used for scientific purposes such as
cosmic ray
Cosmic rays are high-energy particles or clusters of particles (primarily represented by protons or atomic nuclei) that move through space at nearly the speed of light. They originate from the Sun, from outside of the Solar System in our own ...
experiments. Further development of
nuclear detonation detection systems was extensive for decades afterward, culminating in worldwide systems by various countries to keep eyes and ears on detecting and verifying the others' nuclear weapon developments. There would also be fixed-wing
United States aerial reconnaissance of the Soviet Union
Between 1946 and 1960, the United States Air Force conducted aerial reconnaissance flights over the Soviet Union in order to determine the size, composition, and disposition of Soviet forces. Aircraft used included the Boeing B-47 Stratojet bomb ...
during the 1950s. Overflights would end in 1960 (
once an aircraft had been shot down by SAMs), and reconnaissance would afterward (for decades) be handled mostly by
reconnaissance satellites and to some extent by aircraft, such as the A-12 Oxcart and SR-71 Blackbird (photography and radar) and RC-135U and similar aircraft (SIGINT including ELINT and COMINT).
Roswell incident
In 1947, a Project Mogul balloon ''NYU Flight 4'', launched June 4, crashed in the desert near
Roswell, New Mexico. The subsequent military cover-up of the true nature of the balloon and burgeoning conspiracy theories from UFO enthusiasts led to a celebrated "UFO" incident.
[ Olmsted writes "When one of these balloons smashed into the sands of the New Mexico ranch, the military decided to hide the project's real purpose." The Official Air Force report (Weaver & McAndrew 1995) had concluded (p. 9) " ..the material recovered near Roswell was consistent with a balloon device and most likely from one of the MOGUL balloons that had not been previously recovered."]
Unlike a weather balloon, the Project Mogul paraphernalia was massive and contained unusual types of materials, according to research conducted by ''
The New York Times
''The New York Times'' (''the Times'', ''NYT'', or the Gray Lady) is a daily newspaper based in New York City with a worldwide readership reported in 2020 to comprise a declining 840,000 paid print subscribers, and a growing 6 million paid ...
'': "...squadrons of big balloons ... It was like having an elephant in your backyard and hoping that no one would notice it. ... To the untrained eye, the reflectors looked extremely odd, a geometrical hash of lightweight sticks and sharp angles made of metal foil. .. photographs of it, taken in 1947 and published in newspapers, show bits and pieces of what are obviously bits of the recovered UFO."
Legacy
Implementation of Mogul's experimental
infrasound detection of nuclear tests exist today in ground-based detectors, part of so-called
Geophysical MASINT
Geophysical MASINT is a branch of Measurement and Signature Intelligence (MASINT) that involves phenomena transmitted through the earth (ground, water, atmosphere) and manmade structures including emitted or reflected sounds, pressure waves, vibra ...
(Measurement And Signal INTelligence). In 2013, this world-wide network of sound detectors picked up the large explosion of the
Chelyabinsk meteor
The Chelyabinsk meteor was a superbolide that entered Earth's atmosphere over the southern Ural region in Russia on 15 February 2013 at about 09:20 YEKT (03:20 UTC). It was caused by an approximately near-Earth asteroid that entered the a ...
in Russia. The strength of the sound waves was used to estimate the size of the explosion.
References
{{Reflist, refs=
[{{cite journal , last1=Frazier , first1=Kendrick , author-link1=Kendrick Frazier , title=The Roswell Incident at 70: Facts, Not Myths , journal= Skeptical Inquirer , date=2017 , volume=41 , issue=6 , pages=12–15 , url=https://www.csicop.org/si/show/the_roswell_incident_at_70_facts_not_myths , archive-url=https://web.archive.org/web/20180720182643/https://www.csicop.org/si/show/the_roswell_incident_at_70_facts_not_myths , url-status=dead , archive-date=2018-07-20 , access-date=20 July 2018]
External links
*Obituary of the man who launched the balloon https://web.archive.org/web/20151117031650/http://www.nmt.edu/news/3704-charles-b-moore-1920-2010
Balloons (aeronautics)
Military projects of the United States
Roswell incident
Soviet Union–United States relations
Projects of the United States Air Force
Cold War military history of the United States