Synonyms: planetoid (literally: planet-like); minor planet.
The asteroids have diameters which range from a few metres up to 1 000 Km. The first asteroids, which remain the most widely known, were discovered at the beginning of the 19th century: Ceres, Pallas, Juno and Vesta; although the IAU reclassified Ceres as a dwarf planet in 2006. Asteroids are distinguished from actual planets by having insufficient gravity to become round in shape and to "clear their orbit" of smaller bodies in the vicinity by attracting them to the surface or in orbit around them as satellites.
Numerous asteroids have orbits that lie between Mars and Jupiter, in the so-called asteroid belt. Ceres, Pallas and Vesta are the three largest bodies in the asteroid belt. Also, Juno is in the asteroid belt.
There is another belt of asteroids in the solar system, the so-called Kuiper Belt which lies beyond the orbits of Neptune and Pluto. The Kuiper Belt is thought to contain a much greater number of asteroids than the asteroid belt. The present consensus is that the Kuiper Belt is made up of matter which was prevented from condensing into one planet - in this case by the pull of Neptune's gravitational field. Pluto has recently been classified as the largest celestial body belonging to the Kuiper Belt and reclassified as a dwarf planet.
The so-called centaurs have also been classified as asteroids. Their orbits around the Sun lie between Jupiter and Neptune, and they would appear to function as a "bridge between asteroids and comets, or/and the ancestors of comets." The most known centaur is Chiron.
Considerable differences of opinion today mark western astrologers’ approach to asteroids. Some astrologers find them meaningless in a horoscope, arguing that there are so many thousands of asteroids in the heavens that they can only be considered as so much “space junk.” Even some committed believers in astrology have difficulty in believing that a small rock chunk named Elvis or Lancelot has much impact on an individual, especially when it makes no major contact with his natal planets or angles. If one uses asteroids with a range of aspects, midpoints, Arabian Parts, and so on, one can probably make a chart express anything one wants—or nothing.
Asteroids are little used today by practitioners of traditional western, horary, or Vedic astrology. Not only are asteroids are invisible to the naked eye, but asteroids simply do not fit easily into these astrological systems.
Some of the first 20th century astrologers to work with asteroids felt that the confusion surrounding asteroids could be minimized if each asteroid signified one or only a limited number of attributes; in contrast with the planets that might each indicate multiple attributes. For example, asteroid 275, Sapientia, would represent the single quality of wisdom; whereas the planet Jupiter signifies wisdom, travel, theology, philosophy, good luck, expansion, and a generally beneficial influence.
This concept of each asteroid representing one quality as expressed by its name, however, troubles other astrologers who are puzzled as to why an arbitrary name, perhaps given by an astronomer without due consideration, should somehow influence human behavior through the operations of a rock the size of an apartment building.
Asteroids do have a following in modern astrology, however. Demetra George’s work on female-named asteroids countered a solar system heavily weighted in favour of masculine-named planets and male-oriented chart interpretations. Other astrologers find that there is a story of mythology behind many of the asteroids’ names, and that once these narratives are understood, an asteroid conjunct a natal planet or angle should give further information on how planets and angles function in the horoscope. For example, if an astrologer is undecided whether Jupiter in a horoscope indicates the traveler or the philosopher, a conjunction with asteroid Sapientia may indicate the philosopher.
Astrologers who use asteroids caution that they cannot be applied indiscriminately. It is important to focus on asteroids whose names are meaningful to the individual person or event. For example, many asteroids are named for astronomers or their family members and associates. It would make little sense to apply these to the chart of composer Wolfgang Amadeus Mozart. However, asteroid Euterpe (81), the classical muse of music, conjuncts Mozart’s Venus within 5 degrees. Venus is the traditional ruler of the fine arts.
One interesting application of asteroids is so-called name-sake asteroids. Not everyone has an asteroid bearing his or her name, but many people do, especially when cognate names, including in in other languages, are considered. For example, Eileen (11836), Helena (101), and Eleonora (354) are variants or foreign-language versions of the English name Helen. In Synastry it is helpful to see how the namesake asteroid of one person falls into the other person’s chart. Former US President Bill Clinton, for example, has asteroid Hillary (3130) conjunct his moon (4 degree orb). Asteroid Michelle is within 3 degrees of US President Barack Obama’s midheaven. While this orb is wide, the placement is consistent with Obama’s crediting his wife with much of his success in life (an MC matter.)
Asteroids themselves cannot cast much of an Orb. Astrologers disagree on whether one should therefore use only tight orbs within a degree in any consideration, or whether one can use the wider orb of the planet they conjunct.
Some asteroids are used more generally to indicate a suite of characteristics. For example, Juno (3)—the mythological wife of Jupiter—may be used to consider marriage prospects in a chart. Because mythological Juno was constantly jealous about her husband’s infidelity, asteroid Juno may indicate both jealousy and faithfulness within a person’s married life. Amor (1221) is considered an indicator of love and affection, ranging from platonic to intimate.
Another area of debate amongst astrologers concerns whether any of the larger asteroids can qualify a ruler of zodiacal signs; and if so which ones, and whether the asteroids thereby depose the traditional planetary rulers. Proponents of assigning Vesta (or Chiron or Ceres, etc.) to Virgo, for example, generally point to strong affinities in the narratives linking the asteroid and sign. Traditionalists, however, point to a standard scheme of planetary rulership (Domicile) going back at least 2000 years, based on a logic of the planet’s distance from the sun and moon. Moreover, astrologers who use house cusp lords (accidental house cusp rulers) need some convincing that asteroids have utility as sign rulers for astrological techniques that go beyond simple match-ups based upon similar characteristics. At present individual astrologers may use particular asteroids or Ceres as the domiciled ruler of a sign, but there is no widespread agreement as to such planet-sign pairs.
Substantial research remains to be done on the asteroids in astrology, together with the transneptunian objects and centaurs. Whether they will fit neatly into pre-existing techniques in astrology, or whether they demand new ways of thinking about our solar system remain to be seen.
Astrodienst’s chart construction page offers over 17,000 asteroids that can be added to its horoscopes.
- The term minor planet, originally used to describe these celestial bodies, show that astronomers were originally reluctant to put them on an equal footing with the major planets in our solar system. In fact, it is not really possible to make a clear distinction between the minor and the (major) planets. On this subject Dieter Koch, who is an advocate of the term minor planet, writes:
"It is actually difficult to say why these celestial bodies should only be 'planet-like' and not planets. Making this distinction based on size is untenable... then again, the expression 'star-like' seems in any case to call for the complementary term 'planet'."
In regard to the argument over size, Koch points to the fact that Pluto's diameter is only 2 320 Km.
Demetra George, 1986, Asteroid Goddesses:The Mythology, Psychology and Astrology of the Reemerging Feminine, ACS Publications, Inc.
J. Lee Lehman, 1988, The Ultimate Asteroid Book, Whitford Press.