Glossary of Terms

The apparent path the Sun traces across the sky over the course of a year, as seen from Earth. This is the plane of Earth's orbit around the Sun. The zodiac constellations lie along this path, and all the planets orbit close to this plane.

An imaginary circle in the sky directly above Earth's equator. It divides the celestial sphere into northern and southern hemispheres. The ecliptic crosses the celestial equator at two points: the vernal and autumnal equinoxes.

The apparent backward motion of a planet as observed from Earth. This is an optical illusion caused by the relative speeds and positions of Earth and the other planet in their orbits. When a planet is retrograde, it appears to move east to west against the background stars, opposite to its normal direction.

The normal, forward (west to east) motion of a planet through the zodiac, as opposed to retrograde motion. When a planet is "stationing direct," it is ending its retrograde phase and resuming forward motion.

A table or data file giving the calculated positions of celestial bodies at regular intervals throughout a period of time. Frequency Forecast uses NASA JPL ephemeris data (DE421) for precise planetary positions.

The movement of a planet through a zodiac sign or across a specific degree. In natal astrology, transits refer to the current positions of planets in relation to the positions in your birth chart.

The moment when a planet enters a new zodiac sign. For example, the Sun's ingress into Aries marks the beginning of astronomical spring in the Northern Hemisphere.

The celestial equivalent of longitude, measuring how far east an object is from the vernal equinox point. Measured in hours, minutes, and seconds (0h to 24h), where 24 hours equals a full circle (360°). One hour of RA equals 15 degrees.

The celestial equivalent of latitude, measuring how far north (+) or south (-) an object is from the celestial equator. Measured in degrees, from +90° (north celestial pole) to -90° (south celestial pole).

Angular distance measured along the ecliptic from the vernal equinox point (0° Aries in tropical astrology). This is the primary coordinate used in astrological calculations, measured from 0° to 360°.

Angular distance north or south of the ecliptic plane. Most planets stay within a few degrees of the ecliptic, but the Moon and some minor bodies can have significant ecliptic latitude.

The horizontal direction of a celestial object measured clockwise from true north. Combined with altitude, it specifies where to look in the sky from a specific location.

The angle of a celestial object above the horizon, measured in degrees. 0° is at the horizon, 90° is directly overhead (zenith).

Relating to the stars. The sidereal zodiac is based on the actual positions of the constellations in the sky. Because of precession, the sidereal zodiac slowly shifts relative to the tropical zodiac by about 1° every 72 years. Frequency Forecast uses the sidereal system to show you where planets actually are among the stars.

Based on the seasons. The tropical zodiac begins at 0° Aries at the vernal equinox (first day of spring) each year. This system, used by most Western astrology, is based on Earth's relationship to the Sun rather than the background stars.

The angular difference between the tropical and sidereal zodiacs. This offset increases by approximately 1° every 72 years due to precession. Frequency Forecast uses the Lahiri ayanamsha, one of the most widely accepted standards.

The slow wobble of Earth's rotational axis, like a spinning top. This causes the vernal equinox point to slowly drift westward through the constellations, completing one full cycle approximately every 26,000 years (the "Great Year").

A zodiac system that includes Ophiuchus (the Serpent Bearer) as a 13th sign, based on the actual IAU constellation boundaries. The Sun passes through Ophiuchus from approximately November 30 to December 17 each year.

The official boundaries of the 88 constellations as defined by the International Astronomical Union in 1930. These boundaries determine exactly which constellation any celestial object is "in" at any given time.

A classification system grouping the zodiac signs by their elemental nature. Fire signs (Aries, Leo, Sagittarius) are associated with energy and action. Earth signs (Taurus, Virgo, Capricornus) with practicality. Air signs (Gemini, Libra, Aquarius) with intellect. Water signs (Cancer, Scorpius, Pisces) with emotion.

A classification system based on how signs initiate or respond to change. Cardinal signs (Aries, Cancer, Libra, Capricornus) initiate action. Fixed signs (Taurus, Leo, Scorpius, Aquarius) maintain and stabilize. Mutable signs (Gemini, Virgo, Sagittarius, Pisces) adapt and transform.

A significant angular relationship between two planets or points in an astrological chart. Aspects describe how planetary energies interact with each other.

Two planets at the same degree of the zodiac (or very close). Represents fusion, intensification, and new beginnings. The energies of both planets merge and work together as one.

Two planets approximately 60° apart. A harmonious aspect representing opportunity, cooperation, and easy flow of energy. Requires some effort to activate but generally supportive.

Two planets approximately 90° apart. A challenging aspect representing tension, conflict, and dynamic friction. Creates pressure that motivates action and growth through overcoming obstacles.

Two planets approximately 120° apart. The most harmonious major aspect, representing natural talent, ease, and flowing support between planetary energies. Often indicates areas of natural ability.

Two planets approximately 180° apart (opposite sides of the zodiac). Represents polarity, awareness through contrast, and the need to integrate opposing forces. Can manifest as external projection or conscious balance.

The allowable deviation from an exact aspect. For example, if a trine is exact at 120° and you use an 8° orb, planets between 112° and 128° apart would be considered in a trine aspect. Tighter orbs (smaller deviation) indicate stronger aspects.

A scale from 0 to 9 measuring global geomagnetic activity. Values of 5 or higher indicate geomagnetic storms. Higher Kp values can affect satellite operations, power grids, and increase aurora visibility at lower latitudes.

A sudden burst of radiation from the Sun's surface, classified by X-ray intensity: A and B (background), C (minor), M (moderate), X (major). X-class flares can cause radio blackouts and are often followed by coronal mass ejections.

A massive burst of solar plasma and magnetic field expelled from the Sun's corona. When Earth-directed, CMEs can cause geomagnetic storms 1-3 days after leaving the Sun, affecting technology and producing auroras.

A continuous stream of charged particles (mostly protons and electrons) flowing outward from the Sun at 300-800 km/s. Solar wind speed and density affect Earth's magnetosphere and geomagnetic conditions.

Extremely low frequency (ELF) electromagnetic waves that exist in the cavity between Earth's surface and ionosphere. The fundamental frequency is approximately 7.83 Hz. Some researchers study correlations between Schumann Resonance variations and biological or geophysical phenomena.

A temporary dark spot on the Sun's surface caused by magnetic field concentrations. Sunspots are cooler than surrounding areas and are often associated with solar flares and CMEs. Sunspot counts follow an approximately 11-year cycle.

A map of the sky at the exact moment and location of birth, showing the positions of the Sun, Moon, planets, and other celestial points. Also called a birth chart or horoscope.

The zodiac sign rising on the eastern horizon at the moment of birth. The Ascendant sets the framework for the houses and represents how you present yourself to the world and your approach to life.

The highest point of the ecliptic in the sky at the moment of birth, representing career, public image, and life direction. The MC is the cusp of the 10th house in most house systems.

Twelve divisions of the chart representing different areas of life (self, money, communication, home, creativity, health, partnerships, transformation, philosophy, career, community, spirituality). House positions are determined by birth time and location.

The two points where the Moon's orbital path crosses the ecliptic. The North Node represents growth direction and life purpose; the South Node represents past patterns and innate abilities. Eclipses occur near the nodes.

A minor planet orbiting between Saturn and Uranus, discovered in 1977. In astrology, Chiron represents the "wounded healer" archetype—areas of deep personal wounds that, through healing, become sources of wisdom and ability to help others.

The angular distance a celestial body is from the observer's meridian, measured along the celestial equator. Used in calculating local apparent positions of celestial bodies.