Nadir
direction pointing directly below a particular location
In astronomy, the nadir is a point "below" a particular location. "Below" means in the same direction of gravity at that location. The nadir is the opposite of the zenith. The nadir is not a real point. It is used as a reference for the location of other things.
![](http://up.wiki.x.io/wikipedia/commons/thumb/4/47/Zenith-Nadir-Horizon.svg/300px-Zenith-Nadir-Horizon.svg.png)
Related pages
changeReferences
change- Glickman, Todd S. (2000). Glossary of meteorology. American Meteorological Society. ISBN 978-1-878220-34-9.
- McIntosh, D. H. (1972). Meteorological Glossary (5th ed.). ISBN 978-0-8206-0228-8.
- Picoche, Jacqueline (2002). Dictionnaire étymologique du français. Paris: Le Robert. ISBN 978-2-85036-458-7.