Long and short ascension
Because the
Earth's axis (see
axial tilt) is tilted relative to the ecliptic, the twelve signs do not take the same amount of time to cross the eastern horizon. At the equator, there is very little difference (Pisces, Aries, Virgo and Libra take slightly less time than the other signs) but as one moves from the equator, larger and larger differences emerge.
In the northern hemisphere, the signs of Aquarius, Pisces, Aries, Taurus and Gemini take much less time than the theoretical two hours to cross the eastern horizon, whilst the signs of Cancer, Leo, Virgo, Libra, Scorpio and Sagittarius take much longer than two hours to do so. e.g. at 50° latitude:
- Pisces, Aries and Gemini take only about fifty-five minutes to cross the eastern horizon (this is referred to as the length of ascension or simply as the sign's ascension)
- Aquarius and Taurus have an ascension of only about seventy minutes
- Cancer and Sagittarius have an ascension of around two and a half hours
- Leo, Virgo, Libra and Scorpio have ascensions of around two hours and forty-five minutes
At higher latitudes, these differences become even more marked. At the latitude of
St. Petersburg,
Russia:
- Pisces and Aries ascend in only thirty minutes
- Aquarius and Taurus ascend in only forty-five minutes
- Capricorn and Gemini ascend in an hour and a half
- actually individual degrees near Sagittarius or Cancer ascend twice as slowly as those near Aquarius or Taurus
- Sagittarius and Cancer ascend in two hours and forty minutes
- Leo, Virgo, Libra and Scorpio take as much as three hours and fifteen minutes to ascend
In the southern hemisphere, long and short ascension are reversed.
Astrologers consider the differences between the rate at which the signs ascend to be of importance. In many house systems, houses can become very large when they cover Aquarius, Pisces, Aries and Taurus because these signs are seen to be much smaller from the perspective of a northern hemisphere observer.
Some astrologers, such as
Richard Nolle, consider the preponderance of Ascendants in signs from Cancer through Sagittarius (known as the
western signs) to be symbolic of the highly relationship-oriented character inherent in a
complex or civilized society as found today in the northern hemisphere but never developed in equatorial or south temperate latitudes where
eastern (Capricorn through Gemini), individual-oriented Ascendants are equally or more common.