Sir Philip Sidney’s Astrophil and Stella sonnet sequence describes the infatuation of Astrophil (“star-lover”) with Stella (“star”). Because of this infatuation, everything that Astrophil sees makes him think of his obsessive desire for Stella. Thus it is not surprising that when he looks into the sky in sonnet 31 and sees the moon, he immediately attributes to the moon many of his own feelings. To do so, of course, is inherently ridiculous since the moon can have no feelings, but Astrophil, as a funny narcissist, sees everything as a reflection of himself and his own emotions.
In the first two lines, Astrophil attributes to the moon many of the standard traits of a Petrarchan lover obsessed with his own desires. Thus he claims that the moon moves slowly (as a depressed lover might), that the moon seems quiet (as would also be true of a melancholy, rejected lover), and that the moon appears pale (again, another conventional symptom of unrequited desire).
In lines 3-4, Astrophil speculates that Cupid (the god of selfish desire) might actually shoot his arrows in the “heavenly place” (that is, in outer space, where the moon is visible). In lines 5-8, Astrophil proclaims that he can see in the moon many of the symptoms of disappointed desire that he recognizes from his own experience.
Finally, in line 9, Astrophil, now certain that he and the moon have much in common because both are frustrated lovers, asks whether in outer space, as on earth, “constant love” (which is what he claims to offer) is regarded as “want of it” (10). In other words, he asks if this kind of “love” (which is not genuine love of another being but is merely love of oneself) is considered unreasonable in the heavens, as it is on earth. Obviously Astrophil himself does not consider his passion unreasonable, but he here reveals that others do (including the target of his affections).
He then asks, in line 11, whether objects of desire are as “proud” in the heavens as they are on earth – an ironic charge since it is Astrophil, if anyone, who is guilty of pride. In lines 12-13, he asks the moon whether heavenly objects of affection behave as women do on earth. Do they want to be desired and yet “scorn” the men who are possessed by desire for them? Finally, in line 14, Astrophil asks the moon if objects of desire in the heavens claim that their ingratitude is really virtue. This is an especially revealing line, because it implies Astrophil’s comic pride (he thinks Stella should be grateful for his attentions). The line also implies Stella’s professed motive in refusing him: the commendable motive of virtue.
In short, this poem, like many others in the sequence, implicitly presents Astrophil as a typical Petrarchan lover: full of desire for a woman who rejects him; frustrated by that rejection; intent on blaming the woman for turning him away; and full of self-pity. Sidney thus makes Astrophil, here and elsewhere, the target of clever comic satire. We should never take Astrophil as seriously as Astrophil takes himself.