The heliacal rising of a star is the annual event when it first becomes visible above the eastern horizon just before sunrise, due to the stars changing position in the sky relative to the day-night cycle as the Earth orbits the Sun. Heliacal rising also occurs with planets visible in Earth's sky, but since they move relative to the Sun, their heliacal risings do not occur annually.
Clearing this mission with the S++ rank in Trial Mode is extremely difficult, since two opportunities to accumulate Kudos via Djinn's Wish are skipped instead of zero or one like in other Trial Mode stages. The only known way to get S++ is to exploit a probable bug: lure the three flying enemies right before Sistina's boss gate so they follow you into the battle, defeat them to get an x4.0 Chain multiplier, fight Sistina without touching the ground to multiply the Kudos you get from damaging her, and finish her with Divine Ruin Heresy before her SP Skill can take away your Chain to get a multiplied Skill Finish bonus.
