Pls could you advise me as to the correct Latin translation of 'celestial light' or 'light of the heavens'? Is it lucis caelum or lumina caelum? Also what would be the correct translation for 'light of the night sky'? Many thanks in advance.
Both "celestial light" and "light of the heavens" translate as “caelestis lux” as well as “lux caelestis” with a different word order that in Latin can be variable for Latin is an inflected language where synctactical relationships are indicated by the ending, not by the order of the words.
Please note that CAELESTIS (adjective, nominative case) means “celestial” as well as “of heaven/heavens”, while LUX (nominative, 3rd.declension) means “light”.
As for “light of the night sky", its translation is “Caeli nocturni lux” where NOCTURNI CAELI (composed of the genitive of CAELUM, 2nd.declension, and the genitive of the adjective NOCTURNUS agreed with CAELI ) means “of the night sky”, while LUX (nominative, 3rd.declension) means “light”.
Lastly, with regard to “lucis caelum or lumina caelum”, I am sorry, but they both are grammatically wrong.