Search Results

An organism that has had its genetic material manipulated or altered in a laboratory setting through the use of genetic or genomic engineering techniques. Genetically modified organisms (GMOs) are microorganisms, plants, or animals that have been…

A weapon that consists of integral rocket propulsion, means of pointing or guiding the weapon's velocity vector to a prescribed orientation at the position and time of rocket engine shutoff or burnout, and a warhead. In certain applications, means…

The art and science of preserving the use of the electromagnetic spectrum for friendly forces while denying its use to the enemy. This is accomplished via use of techniques, devices, and equipment by an adversary to deny or counteract an enemy's use…

Optical instruments that establish an optical line or axis for the purpose of aiming a weapon. The axis includes the observer's eye, a suitable mark in the instrument, and the target. For a pistol, the traditional iron sights employ a rear notch and…

The body of knowledge that concerns the fundamental nature, function, development, and use of formal models in science and technology. In its most general sense, a model is a proxy. A model is one entity used to represent some other entity for some…

The Nobel Prizes for 2020 included the following awards for scientific disciplines. Chemistry The chemistry prize was awarded jointly to Emmanuelle Charpentier of the Max Planck Unit for the Science of Pathogens, Berlin, Germany; and Jennifer A.…

A highly ambiguous term that designates four different concepts: (1) objective pattern (or natural regularity), (2) formula purporting to represent an objective pattern, (3) law-based rule (or uniform procedure), and (4) principle concerning any of…

The study of matter, energy, and forces. Physical science is generally considered to include astronomy, chemistry, geology, mineralogy, meteorology, and physics. These fields overlap more or less, as illustrated by astrophysics, chemical physics,…

An attempt to explain a certain class of physical phenomena by deducing them as necessary consequences of other phenomena regarded as more primitive or fundamental and less in need of explanation. When formulating a physical theory, any fundamental…

An expendable device that enables aircraft to detect underwater objects, such as submarines, acoustically. Acoustics is the preferred energy form for use in salt water, because it tends to be the least attenuated by the medium.A sonobuoy consists of…

An autonomous undersea vehicle that can be launched from submarines, surface ships, or aircraft to attack enemy submarines and surface ships. An acoustic torpedo is a sophisticated weapon. Its main components are a guidance and control system, a…

That category of weapons which are typically delivered on target by fixed or rotary-wing aircraft, with the exception of nuclear weapons. Specifically included are guns and ammunition, rockets, free-fall bombs, cluster weapons that consist of a…

The use of live nonhuman animals for scientific research and experimentation. Animal testing has been a cornerstone of biomedical research, having contributed greatly to the understanding of human biology, to the unraveling of the complex underlying…

All measures required to combat enemy submarines, including strategy, operational employment of forces, tactics, and a wide variety of equipment and weapons to find and destroy submarines and to neutralize their weapons. Goals The key physical facts…

The weapons, equipment, and supplies that permit lethal or nonlethal devices to strike their targets. Armaments can be classified as field artillery, individual and crew-served weapons (infantry), armor and antiarmor, antiaircraft, helicopter…

The branch of applied physics which deals with the motion of projectiles and the conditions governing their motion. Ballistics is, for practical purposes, subdivided into exterior and interior ballistics. Exterior ballistics begins at the instant a…

A discipline concerned with the application of ethics to biological problems, especially in the field of medicine. Bioethics is a broad term that encompasses the environmental, ethical, legal, and social implications of agriculture, life sciences,…

A burst of electromagnetic energy. In a military context—and the subject of this article—an electromagnetic pulse (EMP) is a transient electromagnetic signal produced by a nuclear explosion in or above Earth's atmosphere (Fig. 1). Though not…

An active and intentional act or practice of putting to death, in a relatively painless way, of persons suffering severely from medical conditions that are incurable, untreatable, or irreversible. Euthanasia is an act by a person, usually a…

Intentional generation of interfering signals in the electromagnetic and infrared spectrum by powerful transmitters as a countermeasure intended to block a communication, radar, or infrared system or to impair its effectiveness appreciably. Radio…

The accumulated body of scientific and technical writing published to serve the informational needs of, primarily, scientists, engineers, and research workers, and, to the extent that it can be understood, the general public. This vast literature is…

Artificial satellites used for a variety of military purposes. Of approximately 4000 satellites successfully launched between 1957 and 1999, about 50% have been either specifically military or usable for military purposes. Major functions of…

Weapons that arm warships. Of the wide variety of such weapons, three important categories are exclusively naval: antiship missiles, torpedoes and mines. Other weapons all correspond to land-based types, but submarine-launched ballistic missiles and…

The Nobel Prizes for 2019 included the following awards for scientific disciplines. Chemistry The chemistry prize was awarded to John B. Goodenough of the University of Texas at Austin, United States; M. Stanley Whittingham of Binghamton University,…

An explosion whose energy is produced by a nuclear transformation, either fission or fusion. Nuclear explosions can be either natural or artificial, for example in the form of a star undergoing a supernova or the deliberate detonation of an…

Multipurpose instruments used to make measurements on a remote object, often an airborne vehicle. These systems are used to provide two basic types of data: accurate measurement of the position, velocity and other motion parameters of the target;…

An optical instrument that permits viewing along a displaced or deflected axis, providing an observer with the view from a position which may be inaccessible or dangerous. Periscopes range in complexity from the simple unit-power tank periscope to…