Other answerers have already given good answers.
You might benefit by reading NASA engineer Albert Taylor's "Soul Traveler," which gives the ways and means he proved he was soul traveling, not simply directing his imagery.
"Watch Your Dreams," Ann Ree Colton, makes the significant point that there are distinct levels within the astral or emotional plane. "The Masters and Their Retreats," Mark Prophet, gives soul travel experiences in the heavenly or etheric plane.
"The Master of Lucid Dreams," Dr. Olga Kharitidi, is also worthwhile.
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