...Aries Mars Sun Jupiter

... Taurus Venus Mercury Saturn and so on.

Declination. The manner of indicating distance N. or S. of the Celestial Equator. The maximum possible declination of the Sun is 23° 28' which occurs at the Solstices, when the Sun passes the Tropics (0°) of Cancer and Capricorn, the limit of the pole's greatest inclination from the plane of the Earth's orbit. The first degrees of Aries and Libra have no declination, since at these points the ecliptic intersects the equator. However, planets at this longitude may have declination. (v. Celestial Sphere.)

The declination of a body whose longitude and latitude are known is found by this formula:

1. Radius (10,000): Tangent of Ecliptic (23° 27'):: sine of longitudinal distance from equinox: tangent of Angle A.

2. Cosine of Angle A: cosine (latitude plus/minus 90°- minus Angle A):: cosine of Ecliptic Obliquity (23° 27'): sine of the Declination. (In this equation the latitude is taken from go, if the latitude and longitude are of different denomination; but when of the same denomination they are added, and from this sum Angle A is subtracted.)

The Moon, Mercury, Mars reach a declination of 27° north, and on rare occasions Venus reaches

28°. Jupiter, Saturn, Uranus and Neptune have practically the same declination as the Sun.

Decreasing or Increasing in Light. From the New to the Full Moon the Moon is increasing in light, and from the Full to the next lunation it is decreasing in light. In a Figure measured from the Sun position, if the Moon is less than 180° counterclockwise from the Sun it was waxing, or increasing in light; if less than 180° clockwise from the Sun it was waning or decreasing in light. Although generally applied to the Moon, it is also applicable to any planet when passing from an opposition to a conjunction with the Sun. It usually occurs when approaching the Sun in the order of the signs; but Mercury and Venus, after they have reached their greatest elongation East or West and are retrograding toward the Sun, decrease in light against the order of the signs. It is generally accepted as weakening the planet's influence.

Decumbiture. Literally, a "lying down." A horary figure erected for the moment when a person is taken ill, wherefrom to judge as to the possible nature, prognosis and duration of the illness.

Deductive Type. Referring to a certain quality or habit of mind that characterizes those born when the Sun was in a Mutable sign: Gemini, Virgo, Sagittarius or Pisces. v. Signs.

Deferent. In Ptolemaic astronomy, an imaginary orbit pursued by a celestial body, around which another body moved in an epicycle (q.v.). A deferent was employed in conditions wherein the natural motion of the body was not involved. The term reflects the fact that Ptolemy was ignorant of the Earth's motion.

Degree. One 360th part of the circumference of a circle. The rough measure of an angle of one degree is the apparent diameter of a dime held at arm's length from the eye. The apparent diameter of the Sun and Moon is about 0.5°. The longest dimension of the bowl of the Big Dipper is about 10°. A degree is divided into 60 equal parts called minutes of arc. The length of a degree of latitude on the Earth's surface increases from 68.71 miles at the equator to 69.41 miles at 90°. The length of a degree of longitude on the Earth's surface varies from 69.65 miles at the Equator to 53.43 at 40°. Degrees are equally applicable to the Zodiac or the Ecliptic. As a time unit it is applicable to the Equator thus:

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