SkyLoka · akandam.com · Method & limits

How the numbers are computed — and where they stop.

Every position in SkyLoka is calculated from first-principles ephemerides that ship in the app. No paid astronomy API, no cached lookup table. Here is exactly what goes into a chart, and — just as important — what an honest chart refuses to invent.

The engine

Register & transits
Full VSOP87 planetary theory (via astronomia) with light-time correction; the Sun from its apparent longitude; the Moon from the ELP series. Arcsecond-class.
In-app live chart
A compact Schlyter ephemeris — small enough to run every frame on a phone, accurate to about an arcminute. Good for signs, nakshatras and the drawn sky; the register uses the heavier VSOP where precision is the point.
Zodiac
Sidereal by default (Vedic). A Modern/Western tropical mode is a toggle — it simply sets the ayanamsa to zero.
Ayanamsa
Chitrapaksha (Lahiri) via the IAU-2006 general precession in longitude, anchored at J2000 = 23.853°. Matches published Lahiri to ~15″. (It does not reproduce Swiss Ephemeris to 1″ — that needs SE's own frame — and we don't claim it does.)
Lunar node
Mean node by default (the panchangam standard, and what the register uses). A true-node toggle is offered; the chart always states which is in use. Ketu is exactly 180° opposite.
Delta-T (TT − UT)
Applied before every ephemeris call in the register and transit pipelines (~69 s today, ~1030 s in the 12th century). It matters most for the fast Moon on historical dates.
Rounding
Stored positions are rounded to 0.01°. A body within half its daily motion of a sign boundary is flagged uncertain rather than silently rounded into a sign.
Interpretation
Kept in a separate layer, labelled as tradition, never written into the same field as a computed number. SkyLoka does not forecast health, money, litigation or marriage, and offers no remedy, gemstone or puja. See the evidence for why.

The limit no honest app can hide

Without a birth time, there are no houses.

The ascendant moves about one degree every four minutes. Without a documented birth time, any ascendant, house cusp, dasha balance or compatibility score is a guess wearing the costume of a calculation. Where the time is unknown, SkyLoka computes what the date honestly allows — planetary signs — and shows nothing where it cannot. Rival apps quietly default the time to noon (or midnight, or sunrise) and print a confident ascendant anyway. That is the fabrication the proof cards expose.

Known limits

The data is public: luminaries.json · placements.json · findings.json. The evidence: /proof/findings. The register: /luminaries. The app: akandam.com.