Nadir

Diagram showing the relationship between the zenith, the nadir, and different types of horizon. Note that the zenith is opposite the nadir.

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.

Nadir Media

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  This diagram depicts a satellite observing backscattered sunlight in the nadir viewing geometry.

Related pages

• Zenith

References

• 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.