🪐 Fixing the Longitude Problem in Astrology: A Simple Macro for Accurate Planetary Positions

How One Small Correction Can Shift the Moon by Degrees — and Restore Precision to Your Charts

For over a century, astrologers have calculated planetary positions based on a timekeeping shortcut that — while convenient — quietly ignores one key variable:

🧭 Your actual longitude.

This oversight can result in planetary positions (especially the Moon) being off by more than 2.5°. That’s enough to alter the sign, the house, or an aspect — and it’s gone largely unchallenged since 1883.

It’s time to change that.

🕰️ The Root of the Problem: Time Zones vs. True Geocentric Time

Modern software typically calculates planetary positions from a chart’s civil or standard time. The default formulas are:

Civil Time (CT) = Universal Time (UT1) – Time Zone offset (if west of Greenwich)
Civil Time (CT) = Universal Time (UT1) + Time Zone offset (if east of Greenwich)

This gives you a clean, standardized time… but it ignores the fact that you're likely not standing on your time zone’s standard meridian. If you were born far east or west of that longitude, your true geocentric time is different.

That difference — called the LMT (Local Mean Time) variation — should be part of the formula.

---

🌍 The Forgotten Variable: LMT Variation

LMT correction = + (λ_obs – λ_std) × 4 / 60 (if east of TZ offset)
LMT correction = - (λ_obs – λ_std) × 4 / 60 (if west of TZ offset)
(in decimal hours)

Where:

• λ_obs is your actual longitude

• λ_std is your time zone’s standard meridian

• The factor “4” converts degrees to minutes of time

• Dividing by 60 gives decimal hours

This small adjustment recalibrates the chart's planetary positions while preserving accurate angles (since sidereal time is already calculated correctly using longitude).

---

🖥️ The Fix in Practice: Astrolog Macro v1.3

For users of the open-source Astrolog software (by Walter Pullen), I’ve worked with Walter to create a macro that performs this correction automatically — just press F3.

Here’s what it does:

• Applies the LMT correction based on your birth longitude

• Recalculates planetary positions accurately using UT1

• Leaves house structure intact (LAST is already correct)

Walter graciously made this possible, even while personally preferring the idea that “time is homogeneous across longitudes” — a belief I gently challenge.

---

🔍 Why It Matters

• The Moon can be off more than 2.5° — affecting signs, houses, aspects

• Planets may shift into a new degree, making Sabian symbol or dwad work unreliable

• Research based on planetary positions loses fidelity

• All of this noise can be corrected — with a few lines of code

---

📣 Take Action: Help Correct the Formula

I’ve launched a public petition to bring this issue to light and push for proper LMT-corrected planetary calculations in all astrology software.

🔗 Sign the Petition on Change.org

This correction doesn’t require topocentric ephemerides, nor does it alter your chart angles. It simply restores accuracy in planetary calculations by honoring the truth of your position on Earth — a truth that’s been neglected for 142 years.

🪐 Astrolog - free astrology software

📨 Want the macro or help integrating it? Just ask — I’m happy to share.

Let’s bring back integrity to astrological timekeeping — one chart at a time.

🕊️
Ron Scott
rscott51.substack.com