degrees: Neil Mann interpretation: begins AD 2150. Dane Rudhyar's interpretation states that the Age of Aquarius will begin in AD 2062. Nicholas Campion in The Book of World Horoscopes indicates that he has collected over 90 dates provided by researchers for the start of the Age of Aquarius and these dates have a range of over 2,000 years commencing in the 15th century AD. The range of dates for the possible start of the Aquarian Age range from 1447 to 3621. Constellation boundary year: Hermann Haupt interpretation: begins c. AD 2595. Astrological predictions There is an expectation that the Aquarian Age will usher in a period of group consciousness. Marcia Moore and Mark Douglas write that the lighting up of the earth artificially by electricity is a sign of the Age of Aquarius. Sub-periods of ages Many research astrologers believe that the astrological ages can be divided into smaller sections along the lines of 'wheels within wheels'. The most common method is to divide each astrological ages into twelve sub-periods. There are two common ways of undertaking this process and two ways of applying these sub-periods. Furthermore, some astrologers divide the ages in different ways. For example, Lcdr David Williams employs a decanate sub-division whereby each age is divided into three equal sections. Aries to Pisces sub-periods The most popular method of sub-dividing astrological ages is to divide each age equally into twelve sub-periods with the first sub-period Aries, followed by Taurus, Gemini, and so on, until the last sub-division, Pisces. Charles Carter was an early advocate of this approach. Technically this approach is based on the twelfth harmonic of the zodiacal signs. Dwadasamsa sub-periods The alternative approach is to apply a method commonly used in Vedic astrology but with long antecedents also in western astrology. This method also divides each astrological age into twelve sub-periods but the first sub-period for each sign is the same as the sign itself, then with the following sub-periods in natural order. For example, the twelve dwadasamsa of Aquarius are Aquarius, Pisces, Aries, Taurus, and so on, until the last dwadasamsa – Capricorn. Technically this approach is based on attributes of both the twelfth and thirteenth harmonics of the zodiacal signs and can be considered to be halfway between the 12th and 13th harmonics. Sub-period direction (forward or retrograde?) There are two ways of applying the above sub-periods to the astrological ages. Natural Order