sidereal

sidereal \sy-DEER-ee-uhl\, adjective:

measured or determined by the daily motion of the stars; of or having to do with the stars or constellations

And everything flying away from everything else for fifteen or so billion years, affinities are established, sidereal liaisons, and the stars slowly drift around one another into rotating star groups or galaxies, and in great monumental motions the galaxies even more slowly convene in clusters, which clusters in turn distribute themselves in linear fashion, a great chain or string of superclusters billions of light-years on end.
-- E. L. Doctorow, City of God

Her description of the calendars that prefaced Books of Hours applies equally to her own book: they make up "a cycle of multiple resonances, spiritual and secular, terrestrial and sidereal, liturgical and agricultural, pagan and Christian, breathtaking in its richness and antiquity and in the geographical spread of its references, but also grounded in the here and now, the everyday".
-- Peter Parker, A remarkable English garden," review of The Morville Hours, by Katherine Swift,, Daily Telegraph, May 2, 2004

by 1634, "of or pertaining to the stars," earlier sideral (1594), from French sidereal (16th century), from Latin sidereus "starry, astral," from sidus "star, constellation," probably from Proto Indo-European base *sweid- "to shine"