Mark Pottenger Astrological Bio

B.A. in Philosophy, UCLA, 1976.

Taught math and astronomy at Astrology Intensives in Los Angeles, CA, Helena, MT, and Zaca Lake, CA from 1976 into 1980s.

Data entry for Astro Computing Services from September 1976 to May 1977. Last weeks mostly worked on research to assist in a time-changes project that years later led to Tom Shank’s The American Atlas and The International Atlas gazetteers. Years later I wrote the conversion of the ACS PC Atlas from Version 1 under DOS to Version 2 under Windows.

Programmer since 1977. Not a practicing astrologer. Mother (Zipporah Dobyns) was a psychological astrologer.

Research Director for the International Society for Astrological Research (ISAR) (1985-1995).

Author: Chiron ephemeris supplement used by both CAO and Phenomena, CCRS Horoscope Program (working astrology and astrology research), FAR (Frequencies for Aspect Research) Program, CCAstEph/CWAstEph Program (asteroids), RID (Rodden-ISAR Databank) program (superseded by IDEA, then AstroDatabank).

Coauthor: With Batya Stark: The Asteroid Ephemeris: Dudu, Dembowska, Pittsburgh and Frigga (ACS Publications, 1982); with Scott G. Vail: Tables for Aspect Research (ISAR, 1986).

Editor: The Mutable Dilemma (CCRS quarterly journal, 1977-1999), Astrological Research Methods Volume 1 (ISAR, 1995).

Much of my programming for astrology has had two primary foci: research and asteroids. All of my programs have many features for the astrological researcher (import, export, control generation, expected frequencies, tallies, queries, quick input, redirectable output, many user-configuration options, etc.). I started work on asteroid orbit calculation in the late 1970s, working in multiple languages on several different machines until a major push in 1994 reached the goal of creating disk ephemerides of all named asteroids (except at that time still lost Albert and Hermes). I implemented the algorithm from Volume 22 of the Astronomical Papers for integrating the outer planets as a step along the way. I gave copies of my outer planet and any-asteroid integration programs to then prominent astrological computing companies in 1982. Asteroid 719 Albert, the last numbered but lost asteroid, was found again in May 2000, closing a small hole in asteroid data. The named but previously unnumbered asteroid Hermes was rediscovered in fall 2003, and assigned the number 69230. As a very close Earth-grazer, Hermes ended up being an even worse calculation challenge than Icarus was many years earlier. I was able to include it after another ephemeris redesign in fall-winter 2003-2004.

Program descriptions

CCRS Horoscope Program (DOS-based, with Macintosh & Amiga versions for some years)

A general-purpose astrological program with emphasis on fast data entry, exploratory techniques and research. Good import/export ability, including ability to direct all printouts to disk. Much more printout oriented than screen interactive. Good batch calculate and print ability.

FAR (Frequencies for Aspect Research) Program (DOS-based)

A specialized tool for research information. Get astronomical background pattern of longitudes of any planet or angles between any pair of planets for a specified period. Results are 360-degree tables and/or graphs. Information can also be useful for teachers.

CCAstEph(DOS)/CWAstEph(Windows) Program (asteroids)

An engine (also part of CCRS) to read asteroid ephemerides and print positions for a chart or print ephemerides. Over 5,300 ephemerides available as of fall 1996 (all named asteroids). When tied to CCRS, a user-configured set of up to 34 asteroids can be used in all CCRS printouts.


The Asteroid Ephemeris Calculator (2003 rewrite) is the program I use, with a number of steps and several support programs, to create astrological ephemerides for asteroids. It depends on a lot of astronomical starting data from the Minor Planet Center. I create ephemerides whenever new asteroid names are published by the MPC.


Before home computers became common, we made our facilities available to other people who wanted charts calculated for research projects. We ran charts for homosexual men, alcoholics, lesbians, gifted children, members of a holy order, astrologers, kundalini, hijack takeoffs, and other things. Most projects were small, with less than 100 cases, but one project involved almost 1,200 charts (that study--by Lynne Burmyn--poked holes in a lot of published "signatures" for homosexuality or lesbianism--none were confirmed).

Since home computers have spread, most of my contribution to astrological research has been making the programs described above. I have still helped with an occasional project, including some of Judith Hill's studies and Sara Klein's accident studies.

The two books mentioned above published by ISAR are purely for research. The Frequency book gives astronomical expected frequencies for aspects between planets. The Methods anthology gives a lot of advice for would-be researchers.

Musings Home