The Horoscope of the Coronation of Their Royal Majesties Christopher and Morgen of Æthelmearci

Note to the reader: In the medieval worldview, it made perfect sense for the activities in the heavens to reflect the activities on earth. The major controversy was over whether it was legal for Christians to make astrological predictions, not over whether those predictions were valid. This horoscope was calculated for the Coronation of the King and Queen of a medieval recreation group, and is written from the perspective of a fifteenth century student of the subject.

Herein is the work of Palmerin da Castelloii. As a student of Domenico Maria Novaraiii, Master of Astrology at the University Bologna since he arrived here in 1483, I have studied the works of the masters: Euclid and Sacrobosco, both the Almagest and the Tetrabiblos of Ptolemy, and the Introduction of Alcabitiusiv. I wish now to employ that learning, by drawing and intepreting the horoscope of the Coronation of Queen Morgen and King Christopher, to know the future of Their reign over the Sylvan Kingdom of Æthelmearc. Ptolemy demonstrates most clearly that knowledge of the future by means of the positions of the planets is both possible and beneficial, and this knowledge could be of benefit to the Realm.

An accurate horoscope requires an accurate knowledge of time and place. The place is simple enough, as this event was held in the Barony-Marche of the Debatable Lands. The Barony is located in the clime of 15 hoursv, or a latitude of 40° 26' 30''vi. The date was 16 September, 2006, but the exact time of Coronation is more problematic, as the only true way to measure the time is to have a skilled astronomer present with an astrolabe to record the elevation of the sun or a star, and unfortunately no such person was present. Hence, I chose noon as the most appropriate time, as the conditions at the sun's zenith influence the entire day.

The position of the sun can be found using the tablesvii or an astrolabeviii. As Sacrobosco tells us, the Sun follows a predictable course around the earth, along the ecliptic, arriving at the first point of Ares at the vernal equinox. By the time of the Coronation, the Sun has nearly arrived at the first point of Libra, where its course crosses the equator at the time of the autumnal equinox. It is only a few degrees shy of that point, having reached the 23rd degree of Virgo.

The Sun's location being known, the positions of the other six planetsix were obtained from the appropriate tablesx.

The essential conditions of the planets, and how their individual powers wax and wane, can be known by reference to their positions in the zodiac. Alcabitius tells us that planet in its housexii is like a man in his home, and in its exaltation like a man in his kingdom and position of honor, and in its term like a man among his kinfolk, and in its triplicity like the man among his supporters, and in its decan like the man it its professionxiii. These things are known by reference to the tablesxiv.

The accidental conditions of the planets are those depend on the relation of the horizon to the zodiac and are most important in determining the character of the horoscope. Once the location of the sun is known, and the clime, we can calculate the ascendant, that degree of the zodiac that is rising at the given time, here noonxv. The length of day on this date is 12 hours and 18 minutes. For a time of noon, exactly half of the total daylength has elapsed, or 6 hours and 9 minutes. If that is converted to degrees using the value of 15 degrees for each hour (since there are 360 degrees in in the zodiac, and they circle the Earth in 24 hours), then we obtain 92° 15' past sunrise. By reference to the table of oblique ascensionsxvi for the clime of 15 hours, we find that the degree of the sun, Virgo 23°, has an oblique ascension of 171° 30'. Adding the elapsed degrees to the location of the sun gives a value of 263° 45'. Referring again to the table of oblique ascensions gives a corresponding value in the zodiac of Sagittarius 6°. This is the ascendant, the degree of the zodiac that is rising over the eastern horizon at noon on September 16.

While it is possible to calculate the degree of the zodiac that is crossing the meridian at a given time and day and clime by reference to the tables of right and oblique ascensions, it is much easier to set the astrolabe so that the ascendant is on the eastern horizon and read off the value at the meridian. For this instance, the local time is noon, so the sun is at the meridian and the degree is Virgo 23°. The degree of the zodiac setting is directly opposite that rising (Gemini 6°), and the degree of the zodiac at the nadir is directly opposite that at the zenith (Pisces 23°). The heavens are divided, and these four points are the cardinal points of the twelve placesxvii. The boundaries of the other places are found by dividing each quadrant as specified by these four degrees of the zodiac into three equal partsxviii.

The lordship of the places is determined by the lordship of the first point of each places, and is calculated by adding the powers of each planet at each point. Alcabitius states that the lord of the places has five powers, the lord of the exaltation has four, the lord of the triplicity has three, the lord of the term has two, and the lord of the decan has one. For the ascendant at Sagittarius 6°, we consult the tables to find the strengths of each of the seven planets at that degree, and add them up according to the values before described. The planet with the greatest number of powers at the first point of the place has lordship over that place, and over the matters contained within that place.

The boundaries of the places and the positions of the planets are all the knowledge needed for the drawing of the horoscope.

Now that the mathematical concerns of essential and accidental conditions have been resolved, and the horoscope drawn up, we turn to the astrologer's art, the interpretation of the configuration so described. As Ptolemy tells us, the planets associated now with one and now with another in their different aspects and experiencing a corresponding tempering of their powers, each produces a character, in its effect, which is the result of the mixture of the natures that have participated, and is complicated. Questions of this kind would reasonably be left to the enterprise and ingenuity of the mathematicianxix.

Let us begin with the meanings of the seven planets as told by Alcabitiusxx.

Saturn is malefic by the effect of extreme dryness and coldness, and indicates melancholy. It indicates the profession of leatherworking, and also when fortunate it indicates trustworthiness in friendship and possession of durable things.

Jupiter is a benefic, masculine planet, favoring moderate heat and moisture, and indicates intellect and vision, and professions such as judging, reconciliation among people, and spreading the good.

Mars is malefic and masculine, and favors heat and dryness. It indicates journeys, and professions involving fire and iron.

The Sun is a benefic in aspect, but a malefic in conjunction, and favors heat and dryness. It indicates the greatest authority, intelligence and light, and gold and all kinds of possessions. Of professions it has ruling and leadership, and the shooting of arrows.

Venus is benefic and feminine, and is the indicator of women. It indicates professions involving musical instruments. When mixed with the Sun, it indicates melodies played before kings and nobility.

Mercury is masculine, but mixed in nature, tending toward whichever planets mix with it. It indicates earthy things and growth.

The Moon is benefic and feminine, and favors coldness and moisture. It indicates messages and arable lands.

The Cauda Draconis is benefic, and indicates rulership, while the Caput is malefic and indicates decrease.

Alcabitius tells us also of the meanings of the places, but it is left to the wisdom of the astrologer to interpret the meanings of the planets therein. The first, fourth, seventh and tenth places are called the cardines, and they are especially important when their lords are found therein.

The first place, which is the ascendant, indicates the soul, life, the beginnings of activities, eloquence, logic and speech. Jupiter is the lord of this cardine, and is found in this place. Alcabitius additionally tells us that the lord of the ascendant entering into the ascendant indicates good fortune and gain. This is auspicious for a coronation, as Jupiter represents judgment and leadership, with good fortune, and in the place covering the beginnings of things.

The second place is the place of property, livelihood and helpers. Saturn is the lord of this place, and no planets are found here. Saturn indicates durable property, but is a malefic influence.

The third place indicates brothers and sisters, messages and messengers, and short journeys. Saturn is the lord of this place, and no planets are found here. Again, Saturn's malefic influence may be felt.

The fourth place is the place of landed properties, outcomes and treasures. Venus is the lord of this place, and the Caput Draconis may be found here. The Caput reinforces the benefic influences of Venus.

The fifth is the place of joy, eating and drinking, and gifts. The Sun is the lord of this place. The Sun is a strong benefic.

The sixth is the place of illness and slaves. The Moon and Venus share the lordship. Both are benefic, and will ameliorate any illness or servitude.

The seventh is the place of women, marriage and controversies. Mercury is the lord of this place, and Mars is found here. Mercury takes the role of the planets it mixes with, in this case a malefic. Controversy is likely to arise, perhaps related to martial matters as indicated by the presence of Mars.

The eighth place indicates fear and death, and opponents. The Moon is lord of this place. The Moon is benefic, and with moisture will ease the anger of opponents.

The ninth place is the place of journeys and roads, and also of science, philosophy and books. The Sun is the lord of this place, and the Sun, Saturn and Venus are in conjunction here. This is a strong conjunction. The benefic influences of the Sun and Venus are not hurt by the strength of Saturn, but rather supported by its intellect and judgment, since the Sun is lord of this place.

The tenth place, the midheaven, is the place of authority and high rank, kingship and fame. Mercury is lord of this place, and Mercury and the Cauda Draconis may be found here. The lord of the tenth by arriving in the tenth indicates good fortune.

The eleventh place is the place of hope and good fortune, praise, clothing, and affection. Saturn is the lord of this place.

The twelfth place indicates enemies and misfortune, sadness, envy and slander, and also riding animals. The Moon is lord of this place, and may be found in this place.

A coronation on this day is a strong and auspicious beginning for rulers of judgment. Messages, though, may go astray. Landed properties and the rulers thereof will be generous. The outcome of the reign will be favorable. There will be joy in feasting, and in the giving and receiving of gifts. There will be little among the populace while these rulers sit the throne. Controversy over martial matters may cause trouble, but opponents will be soothed, and controversy will not lead to war. Science and learning will flourish during this reign, and the study of books and of music. Those crowned on this day will have good fortune and fame. Hope may dim, but misfortune and sadness will soon passxxi.

The horoscopexxii of the coronation of Christopher and Morgen of Æthelmearc.


Alcabitius. 2004. Al-Qabisi (Alcabitius): The Introduction to Astrology: Editions of the Arabic and Latin Texts and an English Translation (eds. Charles Burnett, Keiji Yamamoto and Michio Yano). London: Warburg Institute.

Chaucer, Geoffrey. 2002. A Treatise on the Astrolabe (ed. Sigmund Eisner). Norman : University of Oklahoma Press. (A different edition attributed to F.N. Robinson is available online at (accessed 2 Feb. 2007)).

de Prusse, Pèlerin. 1995. Pèlerin de Prusse On the Astrolabe: Text and Translation of his Practique de Astralabe (eds. Edgar Laird and Robert Fischer). Binghamton, N.Y. : Medieval & Renaissance Texts & Studies.

Euclid. 1998. Elements. Placed online by D.E. Joyce at (accessed 5 Feb. 2007).

Evans, James. 1998. The History and Practice of Ancient Astronomy. Oxford: Oxford University Press.

Grendler, Paul F. 2002. The Universities of the Italian Renaissance. Baltimore: Johns Hopkins University Press.

North, John David. 1988. Chaucer's Universe. Oxford: Clarendon Press.

Ptolemy. 1990. The Almagest (ed. R. Catesby Taliaferro). In: Ptolemy, Copernicus, Kepler. Great Books of the Western World No. 15. 2nd ed. Chicago: Encyclopædia Britannica.

Ptolemy. 1940. Tetrabiblos. Loeb Classical Library No. 1 (ed. Frank Egleston Robbins). Boston: Harvard University Press. Placed online by Bill Thayer at (accessed 2 Feb. 2007).

Sacrobosco, Johannes de. 1949. The Sphere of Sacrobosco and its Commentators. (ed. Lynn Thorndike). Chicago: University of Chicago Press.

Scott, Brian. 2005. Fifteenth Century Italian Men's Names. Taken from Thorndike, Lynn. 1975. University Records and Life in the Middle Ages. New York: W.W. Norton & Co. Online at: (accessed 3 Feb. 2007).

Tester, S. Jim. 1987. A History of Western Astrology. Woodbridge, Suffolk: Boydell Press.


i (back) This article is written from the point of view of a late fifteenth-century astronomer, and based as much as possible on the sources that would have been used by this hypothetical scholar. Several secondary sources were of use in figuring out the details of the period texts. Evan's book (1998) is fantastic, and I highly recommend it. North 1988 and Tester 1987 were both useful for filling in gaps between my modern understanding of astronomy and the medieval understanding. I had two motivations for this project. First, a fascination with this timeperiod, when the modern practice of science was beginning to develop, but the medieval geocentric cosmology still continued. Second, the practice of astrology permeated much of medieval life, and can provide insight into the prevailing worldview that we have completely lost in the modern world, and do not much consider within the SCA. Besides the predictions that have survived as modern superstition, astrology was essential for the proper practice of medicine, and for many other activities.

ii (back) The name Palmerin da Castello is a composite of two names on the rolls of the University of Ferrara for 1473-4 (Thorndike 1975, as found in Scott 2005).

iii (back) Novara was recorded in the rolls of the University of Bologna as professor of astronomy (including astrology) from 1483-1504 (Grendler 2002). Incidentally, Nicolaus Copernicus arrived here in 1496 to study astronomy. The University of Bologna was a leading center for astronomy.

iv (back) Grendler (2002) lists the standard canon of Renaissance astronomical instruction. The major works I have consulted are listed above: Euclid, Elements (an essential underpinning of medieval astronomy; Joyce 1998); Sacrobosco, De Sphaera from the thirteenth century (ed. Thorndike 1949); the second-century works of Ptolemy, Tetrabiblos (ed. Robbins 1940), and Almagest (ed. Taliaferro 1990), and Alcabitius (al-Qabisi), Introduction to the Art of Astrology (eds. Burnett et al. 2004). Other texts that I have not yet obtained in English translation include: Theorica Planetarum (anonymous), and the eight-century text by Messahala (Masha'allah), A Treatise on the Astrolabe, for which I have substituted the fourteenth-century texts Geoffrey Chaucer's Treatise on the Astrolabe (ed. Eisner 2002) and Pelerin de Prusse's Practique de Astralabe (eds. Laird and Fischer 1995), which are derived from Messahala's earlier work. To preserve the medieval deference to authority and the flow of the text, when Ptolemy is cited as authority, the material is from Tetrabiblos. The texts of Alcabitius and Sacrobosco are also cited, and all are from the volumes cited here. Despite the centuries of difference in date, a fifteenth-century scholar would have been using all of these texts, but probably in fifteenth-century editions with accompanying commentary.

v (back) That is, the maximum day length of the year, on the summer solstice, is 15 hours (or a bit under, in the case of Pittsburgh). This was a common classical and medieval method for specifying the latitude of a city.

vi (back) Latitude was also specified numerically, as here, in the form of degrees, minutes, seconds. Alcabitius explains the use of thirds, fourths, and so on, but that level of precision is not justified by the level of observational accuracy available.

vii (back) Palmerin would have had access to astronomical tables containing the position of the sun, planets, and calendrical information. The Alphonsine tables were listed as part of the standard curriculum, but at some universities the master of astrology was required to produce new tables each year (Grendler 2002).

viii (back) I used tables in the medieval manner that I calculated following the explanations of Evans (1998), and also an astrolabe that I constructed based on the same source (more information). Unless otherwise noted (as for the positions of the planets), I did all the calculations myself, following the methods employed by Ptolemy and those who followed him, but using a spreadsheet for the arithmetic. I'm also working on a notebook of astrological tables.

ix (back) The medieval (pretelescopic) scholar recognized seven planets, including the two luminaries (in order from the Earth out): Luna, Mercury, Venus, Sun, Mars, Jupiter, Saturn.

x (back) While Palmerin would have been referring to astronomical tables, I used the modern equivalent: the NASA Jet Propulsion Laboratory's HORIZONS Online Ephemeris at

xi (back) The Caput Draconis (Head of the Dragon) is the ascending node of the moon, where its path crosses the ecliptic heading northwards, and was treated like a planet. The Cauda Draconis, Tail of the Dragon, is the opposite point of the zodiac.

xii (back) Each planet is most powerful in two of the signs of the zodiac, and the luminaries each in one. These are called their houses. For example, the Sun's house is Leo.

xiii (back) The zodiac is divided and subdivided in various ways, and the planets that are strengthened or weakened in each division are listed. The house is defined in the previous footnote, and the exaltation is another sign of importance. Ptolemy describes the exaltation as the place where the planet's powers begin to increase (Tetrabiblos). The triplicity is a three-sign group and is ruled over by different planets in the day and the night, the term is an irregular section of a sign, and a decan is a third of a sign.

xiv (back) The rulers of each of these divisions are presented in tabular form in both Alcabitius and Ptolemy. The houses, exaltations, triplicities and decans are standard, but the terms are the subject of much dispute. Ptolemy presents several different tables of the terms, two of which are attributed to the Egyptians and the Chaldean.

xv (back) A brief note on time: Astronomers of the period (and everyone else) used seasonal hours rather than equal hours, with the day divided into twelve hours, and the night also into twelve. During the summer, daylight hours would be longer than those of the night, and the reverse in the winter. Noon is the time when the sun is at its highest. Evans (1998) does a nice job explaining this.

xvi (back) Although each sign of the zodiac spans 30 degrees, they do not all rise in the same amount of time (Evans 1998). During one hour, 15 degrees of the celestial equator will rise, but the zodiac is tilted with respect to the equator, so a particular segment of the zodiac may rise faster or slower than the equivalent segment of the equator. After 24 hours, both 360° of the equator and 360° of the zodiac have risen. A table of oblique ascensions gives the rising time of each segment of the zodiac at a specified latitude, while a table of right ascensions gives the rising time of each segment for a observer at 0° latitude (on the equator, the right sphere). I calculated the table of oblique ascensions for the latitude of Pittsburgh, and used it in these calculations.

xvii (back) Although modern newspaper astrology concentrates on the zodiac, specifically on the sun sign, medieval astrology was far more interested in the places, a division of the celestial sphere into twelve based on the degrees of the zodiac that were rising, setting, directly overhead and directly below. Each of these places described a slice of human life, as they covered a slice of the heavens. They are also sometimes called "houses", but I will continue to call them places to avoid confusion with the houses of the planets.

xviii (back) There are a number of competing and conflicting ways to divide the heavens into houses. I chose one commonly applied in the Middle Ages, but it is not the only one. Tester (1987) and North (1988) both discuss the different systems in more detail.

xix (back) Quoted from the Tetrabiblos with minor modifications and deletions.

xx (back) For ease of presentation, all material on the planets and places is from Alcabitius. Ptolemy's interpretations are very similar, but more heavily influenced by the four qualities of heat, moisture, coldness and dryness. This section consists of little other than the parts I considered relevant, either quoted or paraphrased. I thought that this repetition of my source material was necessary so that the modern reader could follow the interpretation.

xxi (back) If the reader is interested in following along, I left the interpretations in the order of the houses from which they derived, rather than rearranging the thoughts into a more coherent flow. Please note that there is a long history of telling powerful people, especially kings, what they want to hear, and tailoring the predictions to facts already known. This is a very simplistic interpretation. I left out many of the staples of medieval astrology – the aspects, the phase of the Moon, and so on – both for reasons of length and because I do not have the years of training that must have been needed for the practicing medieval astrologer to be fluent in this idiom.

xxii (back) The medieval horoscope was oriented towards the houses rather than the signs of the zodiac. There were two basic diagram types. In both, the first house begins with the ascendant – the degree of the zodiac rising at the moment for which the horoscope is cast. The ascendant is in the east, on the left of the diagram (Sag 6 in this case). The diagram “turns” clockwise, so the second house is adjacent to the first in a counter-clockwise direction; the second house rises immediately after the first. The degree of the zodiac at the nadir forms the beginning of the fourth house, the degree setting the seventh, and the degree directly overhead begins the tenth house. The positions of the planets are shown in their proper houses, and labeled with the appropriate sign and degree.