Fandom has this general headcanon that Jackie is seen as the sun/sunshine by Hyde. He relates day’s light and warmth with her: as a person, his lover, a friend, all of Jackie is like the sun. As it light your every moment, it also burns you in its most cruel ones. Yes, she’s like the sun.
So in the poem, Jackie talks about Hyde using astrology images. He is her entire universe, all the stars and the answers are in him. He has the moon in his eyes and the galaxies on his back, and when he kisses her, something new is born in a explosion, like the big-bang.
Jackie is in love with him, he has the sun at his feet.