Planetary Aspects and Transits
Hermetic Systems
German version
There are many astrology programs available that will calculate, display and print natal charts — some of which have excellent graphics and produce artistic output. There are also programs that attempt to calculate everything that any astrologer ever supposed to exist. Planetary Aspects and Transits is different, and much easier to use (and to understand) than most astrology programs. Unlike the usual programs, this software makes hardly any mention of astrological signs, and no mention of houses, but rather concentrates (as its name says) on planetary aspects and transits, and how these change over time. This program does not require the use of any other astrology program, but if you already have one of them then this is a very useful addition.

via Paymate
(10% discount)
via Kagi
via Share-it
or via PayPal
Planetary Aspects and Transits is a Windows program to:

This program supports both the tropical zodiac and the sidereal zodiac.
Here is a screenshot of its tabular output:

An 'r' following the longitude of a planet indicates that the planet is retrograde (in this example, Neptune and Pluto). An angle value shows difference of the aspect from exactness (so 0°0' is exact). A '-' or '+' shows whether the aspect is decreasing ('-') or increasing ('+') at the date and time shown, or in other words, whether the aspect is applying ('-') or separating ('+').

Clicking on the 'Display chart' button (in the above example) produces a graphical representation:

Lines joining planets are colored yellow for conjunctions, mauve for oppositions, red for squares, green for trines and light blue for sextiles. The colors of the lines and the values of the orbs for each aspect, can be set by the user. A line joining two planets is thicker if their aspect is close (less than 1°). Retrograde planets are underlined.

Clicking on the 'Run' button steps forward by a day (or week, month or year) repeatedly until stopped, as shown below (step = 1 day) for the period June 9 through June 30, 2010. (If this image does not change then you will have to enable animated images in your browser.)

Click on this link for an illustration of the use of this software.

Some may view the observed consistency of correlation between patterns of human experience and planetary movements as evidence that history has, in some essential way, already been determined in its basic outlines ...  Rather than reinforcing a sense that one is bound by a definite fate, however, knowledge of upcoming world transits, like the knowledge of one's personal transits and natal chart, can open the possibility of a more informed and creative response to the archetypal forces at work at any given time.  — Richard Tarnas, Cosmos and Psyche, p.480

You do not have to know much about astrology to benefit from using this program. But you must have some basic understanding of aspects and transits and of the character of the planetary archetypes, which are explained in Richard Tarnas's book Cosmos and Psyche. In this book he draws attention to the correlation between planetary aspects (mainly conjunctions and oppositions of the outer planets) and both world events and events in the lives of significant people.

For example, from July 11 through July 24, 1609, Jupiter and Uranus were in exact (less than 1°) conjunction. Richard Tarnas says that discoveries in science tend to be correlated with Jupiter-Uranus conjunctions. In the summer of 1609 Kepler published his revolutionary work Astronomia Nova (containing his first two laws of planetary motion) and Galileo made the first public demonstration of his telescope. From December 20, 1609, through March 14, 1610, Jupiter and Uranus were continuously conjunct to within 4°. During this time Galileo made numerous discoveries with his telescope and on March 12 published his findings in his epoch-making Siderius Nuncius.

Jupiter and Uranus were again in exact (less than 1°) conjunction from October 12 through 26, 1900. At a meeting of the German Physical Society on October 19, 1900, when Jupiter and Uranus were within 0°9' of conjunction (and Saturn and Neptune within 1°0' of opposition), Max Planck announced his hypothesis that radiant energy is emitted and absorbed in discrete quanta, thereby initiating the development of quantum mechanics.

Richard Tarnas gives many examples of such correlations, not only in the field of science but also in other areas such as literature and in the domain of world events (particularly wars and revolutions). This software provides a way to check (and confirm) the claims made by him in support of his principal thesis that there is an overall (synchronistic) correlation between planetary aspects and terrestrial events, in accord with the ancient Hermetic dictum, "As above, so below".

In Cosmos and Psyche Richard Tarnas writes that

the five major aspects [conjunction, opposition, square, trine and sextile], and a progressively deepening understanding of the specific meanings of the ten planetary archetypes [the Sun, the Moon and the eight planets from Mercury through Pluto], formed the essential theoretical structure for the research surveyed in this book. Though many other factors, such as the twelve zodaical signs (Aries through Pisces) and the twelve diurnal sectors of the chart called houses, play a significant role in both traditional and comtemporary astrological practice, I consistently found that it was correlations involving the major planetary aspects in natal charts, personal transits and world transits that seemed to represent the fundamental core of the astrological perspective ...

Following Richard Tarnas, and in contrast to traditional astrology, this software thus makes no mention of houses and little mention of astrological signs. The positions of the Sun and the planets are shown by their celestial longitudes at a specific date and time, where zero degrees corresponds to zero degrees Aries, which is either the direction of a line from the Earth to the Sun at the exact time of the vernal equinox (in the tropical zodiac) or the direction of a particular point in the constellation of Aries (in the sidereal zodiac). This software supports both zodiacs, and the position of the planets in a selected zodiac is shown.

User Manual

Other pages in this section:

Trial version: A trial version of Planetary Aspects and Transits can be downloaded from this website for the purpose of evaluation of the software. Click on the following link for further information:

Download Planetary Aspects and Transits ...


via Paymate
(10% discount)
via Kagi
via Share-it
or via PayPal
Price and ordering: A single-user license for Planetary Aspects and Transits costs US$29.45, €23.95 or £19.75 (excluding any sales tax). Purchase via any of the links at right.  After a user license has been purchased an activation key will be sent by email to make the software fully-functional. An activation key can be sent immediately if purchasing via Paymate.  (How?)

We surveyed 30 commercial Windows astrology programs and found the average price to be about US$198.

Refund: A refund will be provided promptly up to 30 days after purchase if the software does not perform satisfactorily.

Updates: Purchasers of a user license for this software are entitled to an update to any later version at no additional cost.

Acknowledgements: Longitudes of the Sun and the planets from Mercury to Neptune are calculated using a translation into C by Peter Meyer of FORTRAN routines which were originally written by astronomer Robert van Gent based on algorithms given in P. Bretagnon & J.-L. Simon, Planetary Programs and Tables from -4000 to +2800 (Willmann-Bell Inc., Richmond, 1986).

Hermetic Systems Home Page All Hermetic Systems Software