Natal Transits Calculator

In the fall of 2012, while auditing a class on Religion and Astrology by professor Ralfee Finn at Hunter College, reading the discussion of natal transits in Richard Tarnas' book Cosmos and Psyche triggered my interest and led me to writing the program below.

Tarnas dedicates to the subject of natal transits of Saturn and Uranus the chapter "Personal Transit Cycles" (p. 109-125), whose main points I condence in the following 2 paragraphs.

The Saturn cycle, he writes, represents the structural unfolding of life. The first Saturn return (or conjunction) happens at about age 28 and lasts 3 years. During this period, you experience your life as coming to an end of an era, the consequences of past actions emerge, and the years of the youth come to a close. The second Saturn return (between 57 and 60)represents the cyclical closure of the structures that had been established three decades earlier, and brings with it an acute awareness that the end of life is now closer. The in-between square and oppostion aspects of Saturn mark periods of critical transformative encounters with authority, with limitations, and with mortality.

The Uranus Cycle has to do with creative awakenings, rebellions, and brakthroughs, sudden change, unexpected disruption of established life structures, psychological turning points, radical changes in philosophical perspective, periods of intensified innovation and discovery, acts of rebellion against various personal and societal constraints, and the like. They also last about 3 years.

Natal transits occur when a planet reaches certain positions in relation to its position at birth. The critical period is within a certain number of degrees before and after the exact aspect, which is called the orb. The usual orb is 5°, but for the conjuctions of Saturn and Uranus the range of influence may be up to 20°.

The 4 radio buttons on the upper row are for the 4 major aspects of conjunction (☌ 0°), square (□ 90° and 270°), trine (△ 120° and 240°), and opposition (☍ 180°). The 2 radio buttons below them are the planets Saturn (♄) and Uranus (♅) whose effects are by far more pronounced then those of the other planets that are rather elusive. The 4 radio buttons to the right of the aspects are the orbs.

The (pre-selected) conjunction of Saturn to the natal Saturn within an 5° orb is probably the most significant of all and you should check it first, especially if you are over 30 years old, before checking the other aspects of Saturn and Uranus.

In the results, I use ➘ and ➚ in the middle of each output line to designate if the aspect occurs when the planet is moving forward or backwards (i.e. is retrograde) when crossing an orb or an exact aspect. A blank in place of an arrow indicates that the planet is moving slowly and it takes more days to cross. The point being crossed is indicated at the end of the line: the orb (e.g. ±5°), or the exact aspect itself (0°).

For the calculator to be loaded you need to have JavaScript enabled in your browser. Please be patient, since your browser may take some time to download the data file, depending on the speed of your Internet connection.

You may enter birthdays between 1900 and 2050. The program finds the transits until 2050 or until one is 100 years old, whichever comes first.

An interesting observation is that the 3 biorhythms, rhythms of 23, 28, and 33 days related to our physical, emotional, and intellectual functioning, seem related to the revolution of Saturn: Their sine-waves start at birth, and meet again at the same point while moving in the same direction after (23 * 28 * 33 =) 21.252d or 58y2m, which is only 3 months shorter than 2 revolutions of Saturn (10759 * 2 = 21.158d or 57y11m), suggesting some relation between them.

If you are interested to explore the rest of the outer planets, you can use the Natal Transits of the 5 Outer Planets Calculator.

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