When the elderly and the unwell should stop eating — the calculation, the source text it comes from, and the resolution of the two competing readings.
One prahar before sparśa, measured from the eclipse's first contact — per સ.જી. ૫.૧૯.૭૭. Precise value 14:28:01.
Computed with Swiss Ephemeris for 53.5769° N, 2.4282° W. All times British Summer Time (UTC+1).
| Event | Local time | Note |
|---|---|---|
| Sunrise | 05:43:41 | Start of day-prahar 1 |
| Sparśa — first contact | 18:13:15 | Falls in day-prahar 4 |
| Maximum | 19:10:03 | 91.45% of the disc obscured |
| Mokṣa — last contact | 20:03:49 | End of puṇyakāl |
| Sunset | 20:44:38 | 40m 49s after mokṣa → not grastāsta |
§119 ન પાળવા યોગ્ય ગ્રહણ — "eclipses not to be observed" — gives four disqualifying tests. Each is checked below.
| Test from the doc | Threshold | Bolton | |
|---|---|---|---|
| Not visible in your region | — | Visible | observed |
| Penumbral (māndya) eclipse | — | Partial | observed |
| Aṅgulālpa — solar, under 1/12 of the disc | < 0.0833 | 0.9255 | observed |
| Shorter than half a ghaḍī | < 12 min | 110.6 min | observed |
Everything downstream depends on this. The doc defines the day and the prahar explicitly, and it does not use clock hours — day-prahars and night-prahars are different lengths.
દિવસ = સૂર્યોદય થી સૂર્યાસ્ત · રાત્રિ = સૂર્યાસ્ત થી સૂર્યોદય
Day = sunrise to sunset · Night = sunset to sunrise. Four prahars in the day, four in the night. One day-prahar = daylength ÷ 4; one night-prahar = nightlength ÷ 4. §120 ગ્રહણનો વેધ — ગ્રહણ સ્પર્શ વેધ ગણિત
દિવસમાં ⟶ ૪ પ્રહર · રાત્રિમાં ⟶ ૪ પ્રહર
દિવસનો ૧ પ્રહર = દિનમાન ÷ ૪ · રાત્રિનો ૧ પ્રહર = રાત્રિમાન ÷ ૪
| Sunset, 12 Aug | 20:44:38 | |
| − | Sunrise, 12 Aug | 05:43:41 |
| = | Dinamāna (day length) | 15:00:57 |
| ÷ | 4 | 4 |
| = | One day-prahar | 3:45:14 |
Why this asymmetry matters. A day-prahar is 68% longer than a night-prahar on this date. That single fact explains why the doc computes the strict rule by a structural table rather than by subtraction — and it is the hinge of the whole §06 argument.
Two consecutive bullets in §120. The first names the quantity; the second names the anchor and carries the scriptural citation.
બાળક, વૃદ્ધ અને રોગી માટે બન્ને ગ્રહણમાં ૧ પ્રહર વેધ માનવો.
"For children, the elderly and the sick, reckon a 1-prahar vedh in both eclipses." §120 · doc line 3554 — the author's summary bullet
સૂર્ય અને ચંદ્રના ગ્રહણ પ્રારંભથી એક યામ પહેલાં પૂર્વોક્ત બાળક, વૃદ્ધ અને રોગાતુરાદિકને ભોજન છોડી દેવું.
"One yāma before the start of the solar or lunar eclipse, the aforementioned children, elderly and ailing should give up eating." §120 · doc line 3555 · સ.જી. ૫.૧૯.૭૭ (Satsaṅgi Jīvan 5.19.77)
The anchor is stated in the ablative: ગ્રહણ પ્રારંભથી — from the start of the eclipse. One yāma (= one prahar) is measured back from sparśa.
| Sparśa — first contact | 18:13:15 | |
| − | One day-prahar (15:00:57 ÷ 4) | 3:45:14 |
| = | Stop eating — children, elderly, unwell | 14:28:01 |
Sparśa at 18:13:15 sits inside day-prahar 4 (16:59:24 → 20:44:38). Subtracting one prahar lands at 14:28:01, inside day-prahar 3 — still within daylight, so the day-prahar length is the correct unit and the subtraction is unambiguous. This point does real work in §06.
The 4-prahar vedh that binds everyone not covered by the exemption. Its method is stated differently, and deliberately so.
સૂર્યગ્રહણ જે પ્રહરમાં સ્પર્શ થતું હોય તે પ્રહરથી (પ્રહરના પ્રારંભથી) ૪ પ્રહર પહેલા વેધારંભ માનવામાં આવે છે.
"Vedhārambha is reckoned four prahars before that prahar (from the start of the prahar) in which the solar eclipse's contact occurs." §120 · doc line 3513
Every row is the same construction: same-numbered prahar of the opposite half of the day. I checked all four.
| Sparśa falls in | Vedh begins at start of | = 4 blocks back from the boundary? |
|---|---|---|
| દિવસ પ્રહર ૧ | રાત્રી પ્રહર ૧ (previous night) | ✓ consistent |
| દિવસ પ્રહર ૨ | રાત્રી પ્રહર ૨ | ✓ consistent |
| દિવસ પ્રહર ૩ | રાત્રી પ્રહર ૩ | ✓ consistent |
| દિવસ પ્રહર ૪ | રાત્રી પ્રહર ૪ | ✓ consistent — our case |
| Sunrise, 12 Aug | 05:43:41 | |
| − | One night-prahar (8:56:58 ÷ 4) | 2:14:14 |
| = | Strict stop = start of night-prahar 4 | 03:29:27 |
A competing reading applies the strict rule's prahar-boundary convention to the 1-prahar case, giving the start of day-prahar 3 — 13:14:10. Both methods are set out below in full, step for step, from the same inputs.
Anchor: ગ્રહણ પ્રારંભથી — the eclipse's start
Source: સ.જી. ૫.૧૯.૭૭ (doc line 3555)
Anchor: પ્રહરના પ્રારંભથી — the prahar's start
Source: borrowed from the 4-prahar rule (doc line 3513)
Both sentences use the frame [X]થી [N unit] પહેલાં — an ablative anchor, then a count back. The author names two different anchors within the same section:
| Anchor | Count | Result | |
|---|---|---|---|
| Strict (line 3513) | તે પ્રહરથી (પ્રહરના પ્રારંભથી) — the prahar's start | ૪ પ્રહર પહેલા | 03:29:27 |
| Relaxed (line 3555) | ગ્રહણ પ્રારંભથી — the eclipse's start | એક યામ પહેલાં | 14:28:01 |
In the strict rule the author adds a parenthetical gloss — (પ્રહરના પ્રારંભથી) — precisely because તે પ્રહરથી alone would be ambiguous. He adds no gloss to the relaxed rule because ગ્રહણ પ્રારંભથી is already unambiguous. To reach 13:14 you must read the relaxed rule's stated anchor as though it said the strict rule's anchor.
The case for 13:14 rests on ૧ પ્રહર વેધ માનવો invoking the table. But that line supplies no anchor at all. It gives a magnitude; the next bullet supplies the anchor and the citation. This summary-then-source pattern is the author's habit throughout §120. The clinching parallel sits six lines above:
ચંદ્રનો ગ્રસ્તોદય થાય તો ૪ પ્રહર વેધ, માટે પૂર્વ દિવસે ભોજન કરવું નહીં.
"If the moon rises eclipsed then it is a 4-prahar vedh, therefore do not eat on the previous day." §120 · doc line 3548
Same N પ્રહર વેધ construction — and the operational consequence is spelled out in plain language, not by table lookup. So ૧ પ્રહર વેધ માનવો is the author naming a quantity, exactly as here. It is not a directive to run the table.
This is the load-bearing argument. Day-prahars and night-prahars are different lengths — 3h 45m 14s versus 2h 14m 14s on this date, a 68% gap.
Now try computing the strict rule by plain subtraction. From an 18:13 sparśa, four prahars back crosses sunrise into the previous night, where the unit changes size. Which four prahars? The question has no answer — a flat subtraction is genuinely undefined for N = 4. So the doc defines it structurally instead, and the table enumerates it.
At N = 1 the problem disappears. One prahar back from a sparśa in day-prahar 4 lands in day-prahar 3 — same half of the day, same unit length, perfectly well-defined. No convention is needed, which is exactly why the doc supplies none. The 13:14 reading imports a workaround built to solve a problem the relaxed rule does not have.
The strongest argument for 13:14 is that vedh might mean "a whole block of time is contaminated," in which case you would stop at the block's boundary. The document's formal definition of the term says otherwise:
૧. પ્રાતઃકાળનો વેધ; સૂર્યોદય પછી ૩ મુહૂર્ત લગી પૂર્વતિથિનો બીજી તિથિને સ્પર્શ થાય તે.
"1. Morning vedh: when the previous tithi touches the second tithi within 3 muhūrtas after sunrise. — Viddha = it sees." § વેધ - પૂર્વવિદ્ધા તિથિ અને પરવિદ્ધા તિથિ · doc lines 3879–3888 · sourced to ધર્મસિંધુ-નિર્ણયસિંધુ
વિદ્ધ = જોવે છે
Vedh is contact occurring within a fixed duration measured from an anchor — 3 muhūrtas from sunrise or before sunset. A duration offset from a reference point, not a block alignment. And વિદ્ધ = જોવે છે — "viddha = it sees": one unit reaches across a span to another. That is structurally the 14:28 method.
Stated honestly: the boundary convention is introduced under the heading ગ્રહણ સ્પર્શ વેધ ગણિત — "computation of eclipse-contact vedh" — which reads as a general method statement. Someone could reasonably hold that the heading governs everything beneath it. That is a real argument, and it is why the document is not airtight.
But it is outweighed. The heading is followed immediately by two specific rules naming ૪ પ્રહર and ૩ પ્રહર — the convention attaches to those, and is never declared universal. It cannot override an explicit, differently-anchored, scripture-cited sentence about the very group in question.
Verdict — 14:28, at roughly 80/20 on the text as written. 13:14 remains a defensible conservative practice and no one is harmed by keeping it; it only means stopping 74 minutes earlier. But it is not what this document says.
A third time was in circulation. It is wrong on two independent counts, and the two causes are separable.
| Candidate formula tested | Time | vs 13:04 |
|---|---|---|
| Day-midpoint at longitude 0° (Greenwich) | 13:04:27 | +27s |
| London day-midpoint | 13:05:01 | +1m 01s |
| Bolton day-midpoint (start of day-prahar 3) | 13:14:10 | +10m 10s |
| Bolton: sparśa − 1 prahar (this report) | 14:28:01 | +1h 24m 01s |
| Bolton: sparśa − flat 4h | 14:13:15 | +1h 09m |
| Bolton: sparśa − flat 3h | 15:13:15 | +2h 09m |
| Bolton: mokṣa − 1 prahar | 16:18:35 | +3h 15m |
Nothing else comes within an hour. 13:04 is the day-midpoint computed at London's longitude — that is, the 13:14 reading, run for the wrong city.
If whoever produced 13:04 is using a panchang or app, it is set to London. Worth correcting regardless of which reading of the rule they prefer — it will be wrong for every future calculation too, not just this one.
| Contact | Nirnay engine (Swiss Ephemeris) | tutiempo.net | Δ |
|---|---|---|---|
| First contact | 18:13:15 | 18:13:08 | 7s |
| Maximum | 19:10:03 | 19:09:56 | 7s |
| Last contact | 20:03:49 | 20:03:43 | 6s |
| Obscuration | 91.45% | 92.5% | ≈1pp |
Both food-stop times were recomputed by hand from the doc's stated method, working from the engine's raw Julian dates rather than its formatted output. Both matched to the second: 14:28:01 and 03:29:27.
What is and isn't verified. The astronomy is cross-verified against an independent source and the arithmetic is independently re-derived. The ruling — which reading of §120 governs, and therefore whether 14:28 or 13:14 is correct — is textual interpretation of this document, not calculation. If the sampradāya has a settled practice on this point, a shastri will simply know it, and that would beat reasoning from the document alone.
| Defect | Effect | Handling here |
|---|---|---|
| ECLIPSE_RITUAL_TIMEZONE hardcoded to Asia/Kolkata | The grastāsta test resolves the civil day in IST, so outside India the flag can silently stay false and invert the fasting ruling | Both boundary flags recomputed from raw contacts against timezone-free sunrise/sunset. Bolton is genuinely ordinary — mokṣa precedes sunset by 40m 49s, so the conclusion is unaffected either way. |
| astronomy.sunApparentAltitude returns 0 for local-partial cases | Understates the sun's altitude (true value ≈ 13° at Bolton) | Field not used or quoted anywhere in this report. |
| Who | Stop eating | Eat again | Basis |
|---|---|---|---|
| Children, elderly, unwell | 14:28 | 20:04, after snān | 1-prahar vedh, સ.જી. ૫.૧૯.૭૭ |
| Everyone else | 03:29 | 20:04, after snān | 4-prahar vedh, §120 table |
Puṇyakāl for japa and dān runs from 18:13:15 to 20:03:49 — the whole time the eclipse is visible, per ચંદ્રગ્રહણ-સૂર્યગ્રહણ જ્યાં સુધી દ્રષ્ટિથી દેખાતું હોય ત્યાં સુધી પુણ્યકાળ (line 3492).
This is an ordinary eclipse, not grastāsta. The fast breaks the same evening after mokṣa and bathing — there is no fasting through the night to the 13th.