Arunachalam Temple An independent guide to Tiruvannamalai

Sources and methods

Where our information comes from, how we rank sources when they disagree, and exactly how we calculate Pournami and festival dates.

Reviewed by the ArunachalamTemple.org editorial team Last updated: Editorial policy

Aerial view of the Annamalaiyar temple complex showing its concentric walls, courtyards and nine gopurams
Photo: Vyacheslav Argenberg, CC BY 4.0, Wikimedia Commons

How we rank sources

When sources disagree, we prefer them in this order, and where they conflict we show the disagreement rather than choosing silently:

  1. Official temple sources: the Arulmigu Arunachaleswarar Temple website run by the HR&CE Department.
  2. Government of Tamil Nadu: notably the Tiruvannamalai District Administration website.
  3. Institutions with first-hand knowledge, such as Sri Ramanasramam for its own ashram.
  4. Reference works, such as Wikipedia articles, which themselves cite published scholarship. We use them for history, and label them as such.
  5. Published calendars and panchangams, for dates not yet officially announced.
  6. Open data, such as OpenStreetMap for map positions.

We do not copy competing guide websites.

How information is labelled

  • Official, Published calendars agree, Calculated, Sources differ. Every festival date carries one of these labels. See the festival calendar.
  • Tradition vs history. Religious narratives are written as tradition (“according to the Arunachala tradition…”), not as historical fact. See Legends of Arunachala and temple history.
  • Requires confirmation. Where official sources don’t publish a detail, such as the daily pooja schedule, we say so on the page.

How dates are calculated

Pournami windows. For each full moon we compute when the moon’s longitude moves from 168° to 180° ahead of the sun’s (the 15th tithi, Pournami). We use standard astronomical series: Meeus’s algorithms for the sun and moon, with ΔT ≈ 70 s. Times are converted to Indian Standard Time and rounded to the minute. For 2026 our start dates match the Girivalam calendar published at thiruvannamalai.in, and times typically agree with printed panchangams to within a few minutes.

Tamil months. The Tamil month of each full moon is the sidereal sign of the sun at that moment (Lahiri ayanamsa).

Festival checks. For Karthigai Deepam we check when the moon is in Krittika nakshatra at dusk during the month of Karthigai. For Maha Shivaratri we check when Krishna Chaturdashi prevails at midnight before the new moon of the month of Maasi. We use these calculations only to check published dates, or to label a date “Calculated” when nothing has been published yet.

The generator is part of the site’s source code (scripts/generate-calendar.mjs), so anyone can reproduce the numbers.

Map positions

Map markers use positions from OpenStreetMap contributors (ODbL), retrieved on 27 September 2026. They are approximate. We don’t plot places we could not find mapped, and we say so beside each map.

Weather

The pilgrim dashboard shows current weather from Open-Meteo, fetched in your browser. If the service is unavailable, the dashboard says so rather than showing a guess.

All sources

Official temple source (HR&CE)

Government of Tamil Nadu

Institution

Reference work

News report

Published calendar

Open data

This is an independent informational guide, not the official temple website. For darshan tickets, sevas and donations, use the official HR&CE temple website.