Noun
natural objects visible in the sky
Source: WordNetSo even if I should say to myself that I will use 'Hesperus' to name the heavenly body I see in the evening in yonder position of the sky, it will not be necessary that Hesperus was ever seen in the evening. But it may be a priori in that this is how I have determined the referent. Saul Kripke
In the present more philosophical era it would hardly be allowable to have recourse to the same method and call it Juno, Pallas, Apollo or Minerva, for a name to our new heavenly body. Source: Internet
Counter-Earth Along with the Central Fire, the "mysterious" Counter-Earth (Antichthon) was the other heavenly body not visible from Earth. Source: Internet
Sextants can be used very accurately to measure other visible angles, for example between one heavenly body and another and between landmarks ashore. Source: Internet