Yes. The heavenly lights were made to be signs because light was given to the earth for the service of man, who, by reason of his soul, is nobler than the heavenly bodies.
Luminaria in signa facta sunt quod in illuminatione terrae intelligitur utilitas hominis, qui secundum animam praefertur corporibus luminarium.
The lights in the heaven are set for signs of changes effected in corporeal creatures, but not of those changes which depend upon the free-will.
Luminaria sunt in signa corporalium transmutationum, non autem eorum quae dependent ex libero arbitrio.
The general division of time into day and night took place on the first day, as regards the diurnal movement, which is common to the whole heaven and may be understood to have begun on that first day. But the particular distinctions of days and seasons and years, according as one day is hotter than another, one season than another, and one year than another, are due to certain particular movements of the stars: which movements may have had their beginning on the fourth day.
In prima die facta est communis distinctio temporis per diem et noctem, secundum motum diurnum, qui est communis totius caeli; qui potest intelligi incoepisse primo die. Sed speciales distinctiones dierum et temporum, secundum quod dies est calidior die, et tempus tempore, et annus anno, fiunt secundum speciales motus stellarum; qui possunt intelligi quarto die incoepisse.
For although the perfect is developed from the imperfect by natural processes, yet the perfect must exist simply before the imperfect. Augustine, however (Gen. ad lit. ii), does not say this, for he says that it is not unfitting that God made things imperfect, which He afterwards perfected.
Licet enim naturali processu ab imperfecto ad perfectum deveniatur, simpliciter tamen perfectum prius est imperfecto. Augustinus tamen hoc non asserit, quia dicit non esse inconveniens quod Deus imperfecta fecerit, quae postmodum ipse perfecit.
As we have said above (Q65, A2), a corporeal creature can be considered as made either for the sake of its proper act, or for other creatures (nor is it untrue to say that a higher creature may be made for the sake of a lower, considered not in itself, but as ordained to the good of the universe), or for the whole universe, or for the glory of God.
Sicut dictum est supra, creatura aliqua corporalis potest dici esse facta vel propter actum proprium, vel propter aliam creaturam (nihil tamen prohibet dici quod dignior creatura facta est propter inferiorem, non secundum quod in se consideratur sed secundum quod ordinatur ad integritatem universi), vel propter totum universum, vel propter gloriam Dei.
Of these reasons only that which points out the usefulness of these things to man, is touched upon by Moses, in order to withdraw his people from idolatry. Hence it is written (Deuteronomy 4:19): "Lest perhaps lifting up thy eyes to heaven, thou see the sun and the moon and all the stars of heaven, and being deceived by error thou adore and serve them, which the Lord thy God created for the service of all nations."
Sed Moyses, ut populum ab idololatria revocaret, illam solam causam tetigit, secundum quod sunt facta ad utilitatem hominum. Unde dicitur Deut. IV, "ne forte, elevatis oculis ad caelum, videas solem et lunam et omnia astra caeli, et errore deceptus adores ea et colas, quae creavit dominus Deus in ministerium cunctis gentibus."