Science / Tides and Currents / Sidereal Time: This is usually defined by astronomers as the hour angle of the vernal equinox. The sidereal day is the interval between two successive upper transits of the vernal equinox. It is to be noted that when applied to the month and year the word sidereal has reference to motion with respect to the fixed stars, while the word tropical is used for motion with respect to the vernal equinox. Because of the precession of the equinox there is a slight difference.
Science / Astrology / Sidereal Zodiac: Based on the division of the circle of twelve constellations: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius and Pisces; the basis for sidereal astrology. MORE
Science / Tides and Currents / Solar Time: Time measured by the hour angle of the Sun. It is called apparent time when referred to the actual Sun and mean time when referred to the mean Sun. It is also classified as local, standard, or Greenwi MORE