Nadir is employed during remote sensing of the atmosphere, as well as when an astronaut faces the Earth while performing a spacewalk. 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
Point-to-point laser technology Point-to-point laser technology Most commonly used for as-built and existing conditions documentation or converting the built environment into a digital format. PPLT has many benefits in creating BIM or (CAD) models. Entering data directly into a CAD- or BIM-enabled work station allows a user or 'surveyor' to capture and confirm a building's geometry on site. This effectively builds a digital model of a building while it is being measured enabling not only speed but accuracy. Additionally, building in real time can eliminate the need for revisits and also minimizes the need for future interpretation and manipulation of measurements and data