Iambic Pentameter Sonnet
If you haven't read it by now, you should know first off that this poem, what with its 14 lines and iambic pentameter, is a sonnet. There are several different types of sonnets, but this one, for the most part, is a Petrarchan sonnet. The first eight lines rhyme ABBA ABBA, where each letter represents that line's end rhyme. So, line 1 rhymes with lines 4, 5, and 8 while line 2 rhymes with lines 3, 6, and 7. This is a favorite scheme of Petrarch's, a sure sign that the poem is following in his formal footsteps.
What's more, the poem falls into two distinct parts, with the second part beginning at line 9. This shift at line 9 is often called the "turn" or volta, and it is one of the distinguishing features of Petrarch's sonnets. The first eight lines (called the "octet") of this poem are all about the speaker's perception of the moon: he looks sad, he climbs slowly, the speaker wonders if he's been assaulted by Cupid, etc. The last six, called the "sestet," are a bit different. They are a series of increasingly frustrated questions that reflect on how the speaker's beloved has been treating him and wonder if female heavenly bodies do the same.
Now, we told you this sonnet is mostly Petrarchan. So, what part of it is not Petrarchan? Well, for one the shift around line 9 isn't as pronounced as it usually in his Sidney's Italian forbear. Beyond that, however, is the rhyme scheme of the sestet, which is CDCDEE. That rhyme scheme is more common in the Shakespearean sonnet. This sonnet, then, is really kind of a hybrid of both the English and the Petrarchan sonnet. Hey, who said you can't branch out a bit?
Usually, sonnets in English are written in iambic pentameter. Surprise, surprise, this one is written in it as well. It's the most famous of all English meters, containing five beats (or feet), each with an unstressed syllable followed by a stressed syllable (which is what an iamb is). Line 4 will illustrate:
That busy archer his sharp arrows tries.
You should hear five iambs in that line ("penta-" means five): daDUM daDUM daDUM daDUM daDUM. While Sidney is often known for playing sophisticated metrical games in Astrophel and Stella, he sticks to iambic pentameter pretty strictly in this poem. Bummer. The only potential speed bump is the word "even" in line 9. Still, this isn't really a speed bump at all once you know that it should be pronounced as one syllable, "e'en" (this is very common in poetry).
So, what do we make of Sidney's strict meter in this poem? Well, for one thing it gives the poem a sense of certainty: we know what the meter is going to be like in every single line. The certainty of the meter balances his doubt about what love is really like up in the heavens (he asks a bunch of questions, which suggests he doesn't really know what happens up there). For a man full of doubt, as Astrophel is, the certainty of the meter provides at least some security.
Except, when the poem throws us for a very small, but significant, 180 in the sestet. Did you notice that "wit" and "yet" don't really rhyme that well? Ahh, the ending T sound rhymes, but the vowels do not. This little bugger goes by the fancy name of a half-rhyme, or slant rhyme, but it might as well just be called a "sort-of" rhyme. It's discordant; it interrupts the regularity of the rhyme and meter that we've seen throughout the poem.
Now you may be thinking Sidney made a mistake. On the contrary, this is actually a very sophisticated little moment. This sort-of rhyme mirrors the speaker's own fears about his beloved's behavior. She apparently loves being loved, but then scorns him. That doesn't really add up now does it? Nope. Neither does that rhyme on "wit" and "yet." Whenever you encounter strange moments in poetry like this one, remind yourself that poets are pretty smart people, and usually do this kind of stuff for a reason.