TKS · PAÑCĀṄGA VALIDATION
TKS VERIFIED
Pañcāṅga Computational Validation
पञ्चाङ्ग-गणना सत्यापन प्रमाणपत्र
This certifies that the published values of the
Rashtriya Panchang · Śaka 1948 (2026–27 CE) राष्ट्रीय पञ्चाङ्ग · शक १९४८ — Positional Astronomy Centre, Kolkata (the edition tested) · packolkata.imd.gov.in/panchang ↗
were tested by TKS against published TKS criteria, for all 365 days at the Central Station 82°30′E · 23°11′N (IST).
TKS Compatible
Computations agree with the declared TKS profile within the set tolerances (tithi, karaṇa, nakṣatra, yoga, sunrise/sunset), all 12 months. Shows consistency with the TKS method — not, by itself, proof of astronomical correctness.
TKS Astronomically Verified
Checked with the TKS engine (accuracy verified against JPL DE440 and NASA) and, for comparison, a separate implementation (Skyfield): tithi, nakṣatra, yoga, solar ingresses (tropical & nirayaṇa), Sun’s nakṣatra entries, sunrise, sunset. Disclosed exceptions: karaṇa (1 entry), moonrise, moonset — see below.
Festival-Rule Verified
Festival dates against declared vrata-decision rules, place and tradition. Not yet applied to this edition.
Scope B · TKS ↔ PAC, shaka 1948
| Item | n | mean s | sd s | max |Δ| s | limit s | |
|---|---|---|---|---|---|---|
| Tithi (end) | 371 | +1.4 | 17.3 | 35.8 | 60 | PASS |
| Nakṣatra (end) | 361 | +0.4 | 17.6 | 38.3 | 120 | PASS |
| Yoga (end) | 388 | +4.2 | 17.7 | 38.2 | 120 | PASS |
| Tropical ingress | 11 | −1.0 | 17.2 | 29.7 | 60 | PASS |
| Nirayaṇa saṅkrānti | 11 | +2.9 | 21.9 | 46.4 | 120 | PASS |
| Sun enters nakṣatra | 23 | +3.4 | 28.3 | 55.2 | 120 | PASS |
| Sunrise | 365 | +3.6 | 19.0 | 40.5 | 60 | PASS |
| Sunset | 365 | −0.3 | 20.5 | 41.4 | 60 | PASS |
| Karaṇa (end) | 709 | +0.4 | 27.5 | 567.0 | 60 | 1 exception |
| Moonrise | 352 | −27.7 | 288.4 | 3238.2 | 120 | 3 exceptions |
| Moonset | 311 | −76.7 | 755.6 | 10574.9 | 120 | 4 exceptions |
PAC prints whole minutes, so ±30 s rounding is inherent (tithi sd 17.3 s = 30/√3). The times served by TKS match its own full-precision engine to 5 ms. For comparison, a separate implementation (Skyfield + JPL DE440s) agrees with TKS within 0.2 s for limb ends and 0.7 s for sunrise/sunset — both read the same JPL data, so this compares implementations, not data.
Disclosed exceptions
- Karaṇa Vaṇija, 21 Oct 2026: PAC 22 Oct 02:27; TKS 02:36:27 — PAC ≈ 9.5 min early. The other 708 of 709 entries are within 37.3 s.
- Moonrise 9–11 Aug (≈ 52 min) and moonset 19–22 Nov (6 min – 2.9 h) differ from TKS; elsewhere the moon items agree (moonrise mean −15 s, moonset +8 s). Both fall just after midnight; PAC’s rule for assigning the day is not published, so the cause is unclear. The separate Skyfield calculation shows the same exceptions.
- Māgha’s printed ayanāṃśa
24° 14′ 80″is invalid (seconds must be below 60). TKS’s Lahiri gives 24° 14′ 16.3″, and the value TKS infers from PAC’s printed Sun times is 24° 14′ 18.0″ — so “80” is most likely a misprint of “18”. Māgha’s sidereal items were checked with TKS’s own Lahiri and are in the table.
Basis of test
Instrument: the TKS engine (events generated at full precision, independent of the stored catalogue). Sidereal items: TKS’s Lahiri profile — it matches PAC’s printed ayanāṃśa (the true ayanāṃśa) to about 1″ at each month start. Horizon: Sun −47′ (PAC’s stated 31′ + 16′). Pass limits were fixed before testing. Comparison: Skyfield + JPL DE440s.
This certificate is issued by TKS. It is not certification or endorsement by IMD/PAC or any government body, and is not government recognition. It states exactly what was tested, for which edition, and with which exceptions.