The Blue Equinox (ISBN 1-57863-353-2) first published in 1919, is a book by English mystic and occultistAleister Crowley, the founder of Thelema, detailing the principles and aims of the secret society O.T.O. and its ally the A∴A∴. It includes such topics as The Law of Liberty, The Gnostic Mass, and Crowley's Hymn to Pan (which rocket pioneer and occultist Jack Parsons would recite before every rocket launch).