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How accurate Viki’s calculations are

In short

Planetary positions come from NASA JPL Horizons ephemerides — the same source professional astrology software uses. It’s a programmatic calculation, not a neural network’s guess. Aspects use honest orbs: if an aspect isn’t there, Viki says it isn’t there rather than stretching it for a prettier reading.

What code calculates and what the network writes

The distinction matters. All numbers — planet positions, house borders, aspect angles, the Pythagorean square — are computed by code from formulas and NASA data. The neural network handles the words: it explains the results in human language.

So Viki cannot invent a Mars position: it arrives from a calculation.

Why JPL Horizons

It’s NASA’s Jet Propulsion Laboratory service, supplying solar-system positions with the highest available precision. That especially matters for Chiron: its orbit is irregular, and approximate formulas drift visibly.

Honest orbs

The orb is the allowance within which an aspect counts. Some services inflate orbs so the reading looks rich. Viki keeps them within reason: a half-degree aspect and a nine-degree «aspect» are not the same thing.

Where precision ends

  • If the birth time is approximate, the houses and Ascendant are approximate — no maths can fix that.
  • If the city is vague, the time zone may resolve wrongly.
  • Interpretation is not a science: different schools read the same configuration differently.

You can verify

Take any professional program or a trusted site, enter the same data and the same house system — the numbers should match. If they don’t, it’s almost always the house system or the time zone.

How it looks in the chat
You’re not making up the planet positions, are you?
No — the code computes them from NASA JPL ephemerides; I only put the result into words. Check in any professional calculator: just set the same house system, or the borders will drift.
Verify with your chart

The program calculates. Viki explains.

Viki is an entertainment and educational service. Tarot readings, astrological calculations and numerology are not medical, psychological, legal or financial advice and do not replace consulting a qualified professional. Decisions made on the basis of the information received remain the responsibility of the user. The service is intended for people aged 18 and over.