Nadir Nadir The nadir (, ; from / ALA-LC: "naẓīr", meaning "counterpart") 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 the nadir is the zenith. Nadir is
Nadir and the sun is 90 degrees below the horizon. This only occurs between the Tropic of Cancer and Tropic of Capricorn at solar midnight. The tropic circles experience this once a year on their winter solstices and all other tropical regions experience this twice. The term nadir also applies to video footage produced for use in Virtual Reality aka 360º video. Cameras capable of capturing spherical footage are generally mounted on a tripod or extension boom that sits directly below and perpendicular to the horizontal plane of the camera lenses (when using two, 180º FOV lenses). In the case of