Day 1 (Moon) - The poem doesn't have much information correlated to any planet. Day 2 (Mars) - The poem mentions red rock. Day 3 (Mercury) - The poem mentions one side that is hot, and one that is cold. Seeing as how Mercury is closest to the sun, it fits, there is also some concept art that leads me to believe Mercury will be playable. Day 4 (Jupiter) - Mentions it's the biggest body. Jupiter being the biggest planet in our solar system, this makes sense. Day 5 (Venus) - Talks of a hot ocean, this coincides with the concept art of Venus. Day 6 (Saturn) - The poem talks of many moons and comets, Saturn has a lot of moons, also it being a gas planet, it talks of the chaotic nature of the planet. Lighting and what not. Day 7 (Sun) - Talks about the burning blaze. I believe the poems are from the Traveler's perspective, not mankind's.