Nadir

The nadir (from Arabic: نظير‎ / ALA-LC: naẓīr, meaning "opposite") is the direction pointing directly below a particular location; that is, it is one of two vertical directions at a specified location, orthogonal to a horizontal flat surface there. Since the concept of being below is itself somewhat vague, scientists define the nadir in more rigorous terms. Specifically, in astronomy, geophysics and related sciences (e.g., meteorology), the nadir at a given point is the local vertical direction pointing in the direction of the force of gravity at that location. The direction opposite of the nadir is the zenith.

Nadir also refers to the downward-facing viewing geometry of an orbiting satellite, such as is employed during remote sensing of the atmosphere, as well as when an astronaut faces the Earth while performing a spacewalk.

The word is also used figuratively to mean the lowest point of a person's spirits, or the quality of an activity or profession.

The term nadir can also be used to represent the lowest point reached by a celestial body during its apparent orbit around a given point of observation. This can be used to describe the location of the Sun, but it is only technically accurate for one latitude at a time and only possible at the low latitudes. The sun is said to be at the nadir at a location when it is at the zenith at the location's antipode.

Nadir (disambiguation)

The nadir is a low or downward point of reference.

Nadir may also refer to:

See also

Nadir (web portal)

Nadir.org is a German web portal, based in Hamburg. It sees itself as "an information system to leftist politics and social movements in the internet". It is one of the oldest German organisations of left groups and for initiatives-based websites. Since 2006, new entries were largely adjusted and a manifesto against retention was published in October 2008. Gradually, it was replaced by the open information platform indymedia. Topics included were anti-fascism, anti-racism and work against sexism.

In particular, the magazines Radikale Zeiten, the "Rote Hilfe Zeitung", Gegendruck, Zeck and Interim were collected electronically.

The term "nadir" means "a point to which a central perspective in an infinitely long distance converges", in the Arabic language "a vanishing point at infinity".

Assessment of the constitutional protection of North Rhine-Westphalia

The Hamburg-based news portal was used, according to the Annual Report of the State Office for the Protection of North Rhine-Westphalia 2004, by left-wing extremists and is referred to as "the oldest left-wing extremist portal".

Learning

Learning is the act of acquiring new, or modifying and reinforcing, existing knowledge, behaviors, skills, values, or preferences and may involve synthesizing different types of information. The ability to learn is possessed by humans, animals, plants and some machines. Progress over time tends to follow a learning curve. It does not happen all at once, but builds upon and is shaped by previous knowledge. To that end, learning may be viewed as a process, rather than a collection of factual and procedural knowledge. Learning produces changes in the organism and the changes produced are relatively permanent.

Human learning may occur as part of education, personal development, schooling, or training. It may be goal-oriented and may be aided by motivation. The study of how learning occurs is part of educational psychology, neuropsychology, learning theory, and pedagogy. Learning may occur as a result of habituation or classical conditioning, seen in many animal species, or as a result of more complex activities such as play, seen only in relatively intelligent animals. Learning may occur consciously or without conscious awareness. Learning that an aversive event can't be avoided nor escaped is called learned helplessness. There is evidence for human behavioral learning prenatally, in which habituation has been observed as early as 32 weeks into gestation, indicating that the central nervous system is sufficiently developed and primed for learning and memory to occur very early on in development.

Learn (disambiguation)

Learning is the act of acquiring knowledge.

Learn may also refer to:

See also

LEARN

LEARN may refer to:

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