The Astral Plane is, in Theosophical and modern occult cosmology, a subtle level of reality lying between the physical world and the higher spiritual planes, composed of a finer, more fluid substance that is directly responsive to thought and emotion. In the layered cosmos mapped by nineteenth- and twentieth-century esotericism (Theosophy, the Hermetic Order of the Golden Dawn, and their successors), the human being possesses, besides the physical body, an astral body of this subtler substance, and it is on the astral plane that dreams, visions, apparitions, and after-death states are located.
Because astral matter takes shape according to feeling and imagination, the plane is described as a world where thoughts become visible forms, beautiful or terrible according to the mind that generates them. A central practice built on this idea is astral projection (or the "out-of-body experience"), in which the practitioner claims to separate the astral body from the physical and travel consciously through this realm. The concept, though it borrows older language of soul and spirit, is characteristically modern in its systematic mapping of planes and bodies, and it became one of the most widely diffused ideas of Western esotericism, feeding directly into New Age and popular spirituality's vocabulary of "energy," dreams, and the journeys of the soul.