NASA

Coordinates: 38°52′59″N 77°0′59″W / 38.88306°N 77.01639°W / 38.88306; -77.01639

The National Aeronautics and Space Administration (NASA) is the agency of the United States Federal Government responsible for the civilian space program as well as aeronautics and aerospace research.

President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA's predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

Since that time, most US space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle, the Space Launch System and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches.

Unidentified flying object

An unidentified flying object, or UFO, in its most general definition, is any apparent anomaly in the sky that is not identifiable as a known object or phenomenon. Culturally, UFOs are associated with claims of visitation by extraterrestrial life or government-related conspiracy theories, and have become popular subjects in fiction. While UFOs are often later identified, sometimes identification may not be possible owing to the usually low quality of evidence related to UFO sightings (generally anecdotal evidence and eyewitness accounts).

Stories of fantastical celestial apparitions have been told since antiquity, but the term "UFO" (or "UFOB") was officially created in 1953 by the United States Air Force (USAF) to serve as a catch-all for all such reports. In its initial definition, the USAF stated that a "UFOB" was "any airborne object which by performance, aerodynamic characteristics, or unusual features, does not conform to any presently known aircraft or missile type, or which cannot be positively identified as a familiar object." Accordingly, the term was initially restricted to that fraction of cases which remained unidentified after investigation, as the USAF was interested in potential national security reasons and/or "technical aspects" (see Air Force Regulation 200-2).

Classified information

Classified information is material that a government body claims is sensitive information that requires protection of confidentiality, integrity, or availability. Access is restricted by law or regulation to particular groups of people, and mishandling can incur criminal penalties and loss of respect. A formal security clearance is often required to handle classified documents or access classified data. The clearance process usually requires a satisfactory background investigation. Documents and other information assets are typically marked with one of several (hierarchical) levels of sensitivity—e.g. restricted, confidential, secret and top secret. The choice of level is often based on an impact assessment; governments often have their own set of rules which include the levels, rules on determining the level for an information asset, and rules on how to protect information classified at each level. This often includes security clearances for personnel handling the information. Although "classified information" refers to the formal categorization and marking of material by level of sensitivity, it has also developed a sense synonymous with "censored" in US English. A distinction is often made between formal security classification and privacy markings such as "commercial in confidence". Classifications can be used with additional keywords that give more detailed instructions on how data should be used or protected.

Unexplained

Unexplained may refer to:

See also

Trousers

Trousers (pants in North America) are an item of clothing worn from the waist to the ankles, covering both legs separately (rather than with cloth extending across both legs as in robes, skirts, and dresses).

In the UK the word "pants" generally means underwear and not trousers.Shorts are similar to trousers, but with legs that come down only to around the area of the knee, higher or lower depending on the style of the garment. To distinguish them from shorts, trousers may be called "long trousers" in certain contexts such as school uniform, where tailored shorts may be called "short trousers", especially in the UK.

In most of the Western world, trousers have been worn since ancient times and throughout the Medieval period, becoming the most common form of lower-body clothing for adult males in the modern world, although shorts are also widely worn, and kilts and other garments may be worn in various regions and cultures. Breeches were worn instead of trousers in early modern Europe by some men in higher classes of society. Since the mid-20th century, trousers have increasingly been worn by women as well. Jeans, made of denim, are a form of trousers for casual wear, now widely worn all over the world by both sexes. Shorts are often preferred in hot weather or for some sports and also often by children and teenagers. Trousers are worn on the hips or waist and may be held up by their own fastenings, a belt or suspenders (braces). Leggings are form-fitting trousers, of a clingy material, often knitted cotton and spandex (elastane).