the great circle passing through the observer's zenith and meeting the horizon due east and west
Examples of 'prime vertical' in a sentence
prime vertical
The prime vertical circle passes through the east and west points of the horizon.
Henry White Warren Recreations in Astronomy (1879). Retrieved in 2019 from Project Gutenberg (https://www.gutenberg.org/ebooks/)
Annual changes of meridional and prime vertical components are small over most oceans.
Jin Yun Guo, Yi Shen, Kaihua Zhang, Xin Liu, Qiaoli Kong, Feifei Xie 2016, 'Temporal-spatial distribution of oceanic vertical deflections determined by TOPEX/Poseidonand Jason-1/2 missions', Earth Sciences Research Journalhttps://revistas.unal.edu.co/index.php/esrj/article/view/54402. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
The meridional and prime vertical components are consistent with the longitude and latitude directions, respectively.
Jin Yun Guo, Yi Shen, Kaihua Zhang, Xin Liu, Qiaoli Kong, Feifei Xie 2016, 'Temporal-spatial distribution of oceanic vertical deflections determined by TOPEX/Poseidonand Jason-1/2 missions', Earth Sciences Research Journalhttps://revistas.unal.edu.co/index.php/esrj/article/view/54402. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)
For positional astronomy, observations were mainly carried out in the meridian or in the prime vertical.
Tapio Markkanen 2013, 'The Development of the Classical Observatory: From a Functional Shelter for the Telescopeto the Temple of Science', Acta Baltica Historiae et Philosophiae Scientiarumhttp://dx.doi.org/10.11590/abhps.2013.2.04. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)