celestial sphere
Concise Oxford English Dictionary © 2008 Oxford University Press:
celestial sphere
▶noun an imaginary sphere of which the observer is the centre and on which all celestial objects are considered to lie.
'celestial sphere' also found in these Oxford entries:
almucantar
- Aries
- armillary sphere
- celestial pole
- ecliptic
- galactic equator
- hemisphere
- horizon
- house
- nadir
- prime vertical
- tropic

