Progressions

Secondary progressions read the sky N days after birth as age N: Valens adds the days of the age to the birth date (Anthologies IX), and Alan Leo's The Progressed Horoscope (1906) made it the modern standard. The angles advance by solar arc in right ascension, Naibod's rate or solar arc in longitude. Solar arc moves every point by the Sun's arc; returns are timed to the second.

• Vettius Valens, Anthologies IX, trans. Mark T. Riley, p. 154
• Alan Leo, The Progressed Horoscope (London, 1906), pp. 25–27
• Dane Rudhyar, The Lunation Cycle (1967): the eight phases of the progressed lunation