Memento Mori et Carpe Diem Scifi Poster

Remember you are mortal and seize the day. This mediaeval Latin phrase based on the works of Horace reminds you to live fully, and appears over the landscape of an alien planet named for the river Styx. The Styx is a river in Greek mythology that formed the boundary between Earth and the Underworld (often called Hades which is also the name of this domain's ruler). The rivers Styx, Phlegethon, Acheron, and Cocytus all converge at the centre of the underworld on a great marsh, which is also sometimes called the Styx. The important rivers of the underworld are Lethe, Eridanos, and Alpheus. The gods were bound by the Styx and swore oaths on it. The reason for this is during the Titan war, Styx, the goddess of the river Styx, sided with Zeus. After the war, Zeus promised every oath be sworn upon her. Zeus swore to give Semele whatever she wanted and was then obliged to follow through when he realised to his horror that her request would lead to her death. Helios similarly promised his son Phaëton whatever he desired, also resulting in the boy's death. According to some versions, Styx had miraculous powers and could make someone invulnerable. According to one tradition, Achilles was dipped in it in his childhood, acquiring invulnerability, with exception of his heel, by which his mother held him. This is the source of the expression Achilles' heel, a metaphor for a vulnerable spot.