| Term | Definition | Contributor | Modified |
|---|---|---|---|
| Celestial sphere | An imaginary sphere, of large but indefinite dimension, used as a basis to define the position coordinates of celestial bodies. The center can be the Earth, the observer, or any other point which play s the role of origin for a given system of coordinates. Seen from the Earth, the celestial sphere rotates around the celestial axis every 23h 56m 04s (the sidereal day), as a result of the Earth's rotation. Two important circles on the celestial sphere are the celestial equator and the ecliptic. The angle between them, about 23.40 degrees, is known as the obliquity of the ecliptic. The celestial equator and the ecliptic intersect at two points, vernal equinox and autumnal equinox. The positions of the celestial poles and therefore that of the celestial equator move gradually on the celestial sphere, due to precession. | Ryan McGranaghan | 2023.04.16 |
| Celestine | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Celestite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Celestite | No definition provided | Christopher Rauch | 2023.12.01 |
| Celibacy | No definition provided | Christopher Rauch | 2023.12.01 |
| cell | In radar usage, a local maximum in radar reflectivity that undergoes a life cycle of growth and decay. The rising portion of the reflectivity maximum is indicative of updraft, and the later descending portion is indicative of a precipitation downdraft. Cells in ordinary convective storms last from 20 to 30 min, but often form longer-lasting multicell convective storms. Cells in supercell storms are more steady and last considerably longer. See also thunderstorm cell. | Ryan McGranaghan | 2023.04.16 |
| Cellamare conspiracy, 1718 | No definition provided | Christopher Rauch | 2023.12.01 |
| cell cluster | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Cell division (Biology) | No definition provided | Christopher Rauch | 2023.12.01 |
| Cellists | No definition provided | Christopher Rauch | 2023.12.01 |
| Cells | No definition provided | Christopher Rauch | 2023.12.01 |
| Cells--Motion | No definition provided | Christopher Rauch | 2023.12.01 |
| Cellular automata | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Cellular pathology | No definition provided | Christopher Rauch | 2023.12.01 |
| Cellular tissue | No definition provided | Christopher Rauch | 2023.12.01 |
| Celluloid | No definition provided | Christopher Rauch | 2023.12.01 |
| Cellulose | No definition provided | Christopher Rauch | 2023.12.01 |
| Cell, Voltaic | No definition provided | Christopher Rauch | 2023.12.01 |
| Celsian | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Celtic | No definition provided | Christopher Rauch | 2023.12.01 |