The sky is visible above, and changes depending on time of day and. At night, the sky has visible stars, moons and Yond.
Astronomy
Astronomy is a form of Cosmology that seeks knowledge about the planes, or a subsection of planes, by studying the sky. The realms of Haeven and Cloudrealm and the moons are considered deeply tied to the sky - and the Great Flow theory about half of all planes can be found ‘up’ above the sky. Astronomers study the movement of the stars, moons and Yond.
Stars
Stars are twinkling lights visible in the sky (mostly at night though some can be seen during the day) which have long been the subject of study, stories, reverence and theories.
Astrology
Astrology attempts to use the movement of stars, moons, and yond to divine Fate.