Bhadra Mukha and Puchha windows

derived.bhadra-mukha-puchha

Vishti Karana duration is partitioned into Tithi-specific Bhadra face and tail windows.

Assurance

Level	Current statement
Documented and traceable	Yes — the canonical record includes the process and a worked example.
Regression or reproduction checked	Linked to 1 repository test file(s).
Independently source-supported	Available only for the explicitly named provenance claims or comparison cells.

Computation method

Method type: formula

Find the Vishti Karana, select Tithi-specific quarters for Mukha and Puchha, scale nominal Ghati widths to the observed Vishti duration, and clip the results to the Panchangam day.

Process

1. Select the first Vishti span; return no windows if none exists.
2. Evaluate Tithi at the Vishti midpoint and read its Mukha/Puchha quarter pair.
3. Divide Vishti into four equal quarters.
4. Place Mukha at the start of its quarter for 5/30 of Vishti and Puchha at the end of its quarter for 3/30.
5. Clip each interval to sunrise through next sunrise.

Formulae

Scaled sub-windows

Q = V / 4; width_mukha = 5V / 30; width_puchha = 3V / 30

• V: observed Vishti duration
• Q: one Vishti quarter

Worked example

Twelve-hour Vishti during Shukla Chaturthi

Inputs

• Vishti: 00:00-12:00 UTC
• Quarter mapping: Mukha 1, Puchha 4

Calculation

1. One quarter is 3 hours.
2. Mukha width is 12h * 5/30 = 2h, starting at quarter 1.
3. Puchha width is 12h * 3/30 = 1h12m, ending at quarter 4.

Result

• Bhadra Mukha: 00:00-02:00 UTC
• Bhadra Puchha: 10:48-12:00 UTC

Method notes

• Only the registered eight-Tithi quarter table is used; unmatched Tithis return no Bhadra sub-window.

Contract

Owning layer: derived
Claim kind: textual-rule
Time basis: Observed Vishti duration expressed on the sunrise-anchored Ghati scale.

Inputs

• Tithi span
• Vishti Karana spans
• Ghati clock

Outputs

• Bhadra Mukha window
• Bhadra Puchha window

References and evidence

Evidence classes: textual
Verification states: verified

The verse mapping and computation contract are registered as verified.

panchangam.bhadra_mukha_puchha

Evidence class: textual
Verification state: verified
Locator: Shubhashubha-prakarana, verses 43-45, printed pp. 20-21 (Internet Archive OCR lines 1743-1797)
Last reviewed: 2026-07-22
Scope: Implements verse 44's Tithi-specific Yama assignments for all eight Vishti-bearing Tithis. The equivalent four-quarter form places Mukha in quarter 1/2/3/4 for Shukla Chaturthi/Ashtami/Ekadashi/Pournami and the paired reverse-order Krishna Tithis, with Puchha in quarter 4/1/2/3 respectively. Mukha occupies five nominal Ghatis and Puchha three; both are scaled from the verse's nominal thirty-Ghati Vishti measure to the observed Karana duration. Verse 45's Bhadra-residence classification is not inferred from these sub-windows.

Sources

• Muhurta Chintamani — Rama Daivajna; Undated Sanskrit text with Hindi commentary, Internet Archive identifier muhurta-chintamani-hindi; authority type: primary_text_hindi_commentary

The complete machine-readable source registry is available in provenance.json. A regression fixture or same-code reproduction is not independent verification.

Reproduce and review

• tests/test_bhadra_mukha_puchha.py

Run the linked tests, then the complete offline contract:

python tools/verify_project.py

Public surfaces

• python-library
• mcp
• ics
• website

Limitations

• This implements the registered Tithi/Yama mapping and does not blend conflicting published tables.

Implementation

• owner: telugu_panchangam/karana_windows.py — compute_bhadra_windows

This route is generated from computations.json. Edit the registry and canonical reference prose in the same pull request as a behavior change.