How does the fluorescence of rotten grass reach the heavenly heart and bright moon? What is rhetoric?

"How can the fluorescence of rotten grass reach the bright moon in the heavenly heart?" Rhetorical device is contrast. "I dare the fluorescence of rotten grass" and "Tianxin Mingyue" are two things to compare. The former refers to the faint light emitted by fluorescein in the dark, and the latter refers to the clear and bright moon in the sky. Contrast is a rhetorical device. By comparing the similarities and differences between the two things, emphasize the differences and characteristics between them. Through this contrast, the author expresses the nobility and beauty of the bright moon in the heavenly heart and the weakness and insignificance of the rotten grass fluorescence, and emphasizes the gap and contrast between them to highlight the beauty and nobility of the bright moon in the heavenly heart.