Construct a Chart

Constructing a chart used to be a time-consuming process, and required a certain amount of mathematical aptitude. Many professional astrologers would send a client’s details away to a specialised company, who would then print out the birth chart and post it back to the astrologer. This not only took time, but meant even a basic consultation with an astrologer could cost a lot of money.

I’ve seen charts done manually by professional astrologers where the finished chart is wrong. Even if your maths is good, it’s easy to make a simple mistake. In addition to the possible errors that you can make with the arithmetic, the pitfalls associated with time zones, whether summer time was in operation and making sure you had the correct longitude and latitude for the person whose chart you were doing would often trip up the most careful astrologer.

I sometimes do charts for people “on the fly” using a tiny computerised gadget that is smaller than my wallet. If I’d wanted to do a chart ten years ago, I would have needed to carry the following essential reference works with me:
 

  • An ephemeris - this is a book giving planet positions for every day in the century (and if I’d wanted to a chart for an historical figure, that would have been a problem)
  • A book containing Tables of Houses - this is for calculating the Ascendant, Midheaven and house cusps
  • A special International Atlas for astrologers containing latitudes and longitudes of all major cities, and also containing time zone and summer time change information

    • To construct the chart, I would need to calculate when the person was born according to a kind of “star time” instead of the time shown on the birth certificate, make various adjustments to take into account the difference between clock time and local time as measured by a sundial, and make sure I was certain about time zones and clock changes. I would need to do this simply to calculate the person’s Ascendant - and even then, it would only be approximate. If I wanted real accuracy, I would also need to make use of a book of old-fashioned logarithm tables.

    Having done this, I would need to carefully draw up a chart using a compass and ruler, and carefully plot the positions of all the planets on the chart. This entire process could take quite a long time, needless to say - no wonder so many people think astrology is complicated!

    Now, thanks to computers, none of this is necessary. A complete beginner can produce a chart in a matter of seconds, without requiring any technical information at all. All that is needed now to construct a chart is to know the date, time and place of birth. No longer does the astrologer need to know the latitude and longitude of the small town in Belgium where the person was born; no more puzzling moments trying to work out whether Daylight Saving Time was in operation in Ontario in September 1953, or which time zone Dallas is in. Nowadays, you can produce a chart either on-line or on your own computer and get on with the real astrology work of trying to interpret it.

    So how much does all this cost? The surprising answer is nothing at all. If you already own a computer, you can get free software for it. If you have access to an Internet connection - and most public libraries provide this free of charge - you can calculate a chart on-line free of charge.

    Take a look at the Using Computers section to see how to do this - the page has links to my website giving step-by-step instructions for installing a program called Astrolog on your own computer, or, alternatively, using the excellent Astrodienst web site to do charts online.

    Chris Mitchell.