Final answer:
Astrophil, the character created by Sir Philip Sidney, longs for his beloved Stella in the sonnet sequence 'Astrophil and Stella'.
Step-by-step explanation:
Petrarch famously wrote about his beloved Laura, and similarly, Sir Philip Sidney had his poetic persona, Astrophil, pining over Stella in the sonnet sequence 'Astrophil and Stella'. This sequence is a cornerstone of Elizabethan sonnet cycles, which were flourishing during Sidney's time. Sidney's sonnets detail the struggles and emotions Astrophil experiences in his unrequited love for Stella, using the template of courtly love that was a popular convention in poetry of that era.