Research note · Dataset schema v1

Open Birth Chart Calculation Test Set

Seven public records compared only where a linked source provides a longitude or sign. Inspect the calculation input, external target, Charting Stars internal acceptance threshold, current engine output, result, and known conflict for every fixture.

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Current output is recalculated from this build. Unlisted positions carry no external-reference claim.

Reference coverageOne mark per sourced check; blanks are not failures.
  1. Albert Einstein8/8
  2. Martin Luther King Jr.2/2
  3. David Bowie3/3
  4. John F. Kennedy3/3
  5. Frida Kahlo3/3
  6. Carl Sagan2/2
  7. Marie Curie2/2
7public fixtures
23external checks
11 / 12longitude / sign
23 / 23passing in this build

01 · Fixture register

Seven records, shown without substitution

The reader distinguishes the linked record from the exact input used by the calculator.

Summary of all seven birth-chart calculation fixtures
Fixture and sourceCalculation inputCurrent chartCited checksKnown caveat
Albert EinsteinAstro-Databank 1879-03-14 · 11:30Europe/BerlinUlm, GermanySun PiscesMoon SagittariusRising CancerASC 98.822° · MC 339.208°8/8 pass5° · 3 signSource caveatThe source uses Ulm LMT (UTC+00:40), while the fixture's Europe/Berlin historical offset is UTC+00:53:28. The stored offset, coordinates, and snapshots remain regression inputs rather than source-verified birth values.
Martin Luther King Jr.Astro-Databank 1929-01-15 · 12:00America/New_YorkAtlanta, GA, USASun CapricornMoon PiscesRising AriesASC 23.037° · MC 284.057°2/2 pass1° · 1 signSource caveatThe source uses 1929 CST (UTC-06:00), while the fixture's America/New_York input resolves to EST (UTC-05:00). Only the published Sun target is compared externally; angles and other precise values remain regression-only.
David BowieAstro-Databank 1947-01-08 · 09:00Europe/LondonBrixton, London, UKSun CapricornMoon LeoRising AquariusASC 303.415° · MC 243.954°3/3 pass1° · 2 signSource caveatThe source presents the 09:00 chart and reports Rodden A, while the stored regression fixture retains AA. The source also documents competing birth times; coordinates remain implementation inputs.
John F. KennedyAstro-Databank 1917-05-29 · 15:00America/New_YorkBrookline, MA, USASun GeminiMoon VirgoRising LibraASC 199.995° · MC 113.773°3/3 pass1° · 2 signSource caveatThe source supports the date, 15:00 time, Brookline, Sun target, and Libra rising sign, but reports Rodden A. The stored AA fixture rating remains unchanged for regression continuity and is not source-substantiated.
Frida KahloAstro-Databank 1907-07-06 · 08:30America/Mexico_CityCoyoacán, Mexico City, MexicoSun CancerMoon TaurusRising LeoASC 143.510° · MC 53.326°3/3 pass1° · 2 signSource caveatThe linked record supports the date, time, place, AA rating, Sun reference, and Leo rising sign. Coordinates and IANA timezone are calculation inputs rather than verbatim source fields.
Carl SaganAstro-Databank 1934-11-09 · 05:05America/New_YorkBrooklyn, NY, USASun ScorpioMoon SagittariusRising LibraASC 207.833° · MC 122.907°2/2 pass1° · 1 signSource caveatThe source gives 17:05 in New York, while this regression fixture uses 05:05 in Brooklyn. The source supports the date, AA rating, published Sun target, and Scorpio Sun sign, but does not verify the fixture time or exact location.
Marie CurieAstro-Databank 1867-11-07 · 12:00Europe/WarsawWarsaw, PolandSun ScorpioMoon PiscesRising CapricornASC 282.071° · MC 228.634°2/2 pass1° · 1 signSource caveatThe source supports the date, noon time, Warsaw, and published Sun target, but reports Rodden AA. The stored A fixture rating remains unchanged for regression continuity.

02 · Reference results

Targets, deltas, internal thresholds, and sources

Longitude checks use circular angular distance against a Charting Stars internal threshold. Sign checks compare the sourced sign only.

Public fixture

Albert Einstein

8/8 cited checks passFixture rating AA · source-reported AA

Calculation input

1879-03-14 at 11:30 · Europe/Berlin

Ulm, Germany

48.4011, 9.9876

Linked source record

1879-03-14 at 11:30 · Ulm LMT (UTC+00:40)

Ulm, Germany

Open Astro-Databank
External targets and signs, with longitude targets evaluated against Charting Stars internal acceptance thresholds, for Albert Einstein
CheckExternal targetCurrent buildEvaluationReference sourceResult
Sun longitude353.500°353.498°Δ 0.002° / internal threshold 1.500°Astro-Databank Published as 23 degrees 30 minutes Pisces.JPL Horizons fixture-instant calculation check Pass
Moon longitude254.533°254.391°Δ 0.141° / internal threshold 3.000°Astro-Databank Published as 14 degrees 32 minutes Sagittarius.JPL Horizons fixture-instant calculation check Pass
Ascendant longitude101.650°98.822°Δ 2.828° / internal threshold 4.000°Astro-Databank Published as 11 degrees 39 minutes Cancer.Pass
Uranus longitude151.283°151.279°Δ 0.004° / internal threshold 1.500°Astro-Charts Published as 1 degree 17 minutes Virgo retrograde.JPL Horizons fixture-instant calculation check Pass
Neptune longitude37.867°37.871°Δ 0.004° / internal threshold 1.500°Astro-Charts Published as 7 degrees 52 minutes Taurus.JPL Horizons fixture-instant calculation check Pass
Sun signPiscesPiscesExact sourced signAstro-Databank Pass
Moon signSagittariusSagittariusExact sourced signAstro-Databank Pass
Rising signCancerCancerExact sourced signAstro-Databank Pass
Inspect all externally referenced positions5 positions
Ascendant 98.822°
Current calculated values for externally referenced positions for Albert Einstein
Body or pointEcliptic longitudeSignMotion
Sun353.498°PiscesDirect
Moon254.391°SagittariusDirect
Uranus151.279°VirgoRetrograde
Neptune37.871°TaurusDirect

Public fixture

Martin Luther King Jr.

2/2 cited checks passFixture rating A · source-reported A

Calculation input

1929-01-15 at 12:00 · America/New_York

Atlanta, GA, USA

33.749, -84.388

Linked source record

1929-01-15 at 12:00 (about noon) · CST (UTC-06:00)

Atlanta, Georgia, USA

Open Astro-Databank
External targets and signs, with longitude targets evaluated against Charting Stars internal acceptance thresholds, for Martin Luther King Jr.
CheckExternal targetCurrent buildEvaluationReference sourceResult
Sun longitude295.133°295.091°Δ 0.041° / internal threshold 1.500°Astro-Databank Published as 25 degrees 08 minutes Capricorn.JPL Horizons fixture-instant calculation check Pass
Sun signCapricornCapricornExact sourced signAstro-Databank Pass
Inspect all externally referenced positions1 positions
Current calculated values for externally referenced positions for Martin Luther King Jr.
Body or pointEcliptic longitudeSignMotion
Sun295.091°CapricornDirect

Public fixture

David Bowie

3/3 cited checks passFixture rating AA · source-reported A

Calculation input

1947-01-08 at 09:00 · Europe/London

Brixton, London, UK

51.4613, -0.1156

Linked source record

1947-01-08 at 09:00 · GMT (UTC+00:00)

Brixton, London, UK

Open Astro-Databank
External targets and signs, with longitude targets evaluated against Charting Stars internal acceptance thresholds, for David Bowie
CheckExternal targetCurrent buildEvaluationReference sourceResult
Sun longitude287.250°287.245°Δ 0.005° / internal threshold 1.500°Astro-Databank Published as 17 degrees 15 minutes Capricorn.JPL Horizons fixture-instant calculation check Pass
Sun signCapricornCapricornExact sourced signAstro-Databank Pass
Rising signAquariusAquariusExact sourced signAstro-Databank Pass
Inspect all externally referenced positions2 positions
Ascendant 303.415°
Current calculated values for externally referenced positions for David Bowie
Body or pointEcliptic longitudeSignMotion
Sun287.245°CapricornDirect

Public fixture

John F. Kennedy

3/3 cited checks passFixture rating AA · source-reported A

Calculation input

1917-05-29 at 15:00 · America/New_York

Brookline, MA, USA

42.3318, -71.1212

Linked source record

1917-05-29 at 15:00 · EST (UTC-05:00)

Brookline, Massachusetts, USA

Open Astro-Databank
External targets and signs, with longitude targets evaluated against Charting Stars internal acceptance thresholds, for John F. Kennedy
CheckExternal targetCurrent buildEvaluationReference sourceResult
Sun longitude67.850°67.843°Δ 0.007° / internal threshold 1.500°Astro-Databank Published as 7 degrees 51 minutes Gemini.JPL Horizons fixture-instant calculation check Pass
Sun signGeminiGeminiExact sourced signAstro-Databank Pass
Rising signLibraLibraExact sourced signAstro-Databank Pass
Inspect all externally referenced positions2 positions
Ascendant 199.995°
Current calculated values for externally referenced positions for John F. Kennedy
Body or pointEcliptic longitudeSignMotion
Sun67.843°GeminiDirect

Public fixture

Frida Kahlo

3/3 cited checks passFixture rating AA · source-reported AA

Calculation input

1907-07-06 at 08:30 · America/Mexico_City

Coyoacán, Mexico City, Mexico

19.3467, -99.1618

Linked source record

1907-07-06 at 08:30 · Local mean time at 99w10

Coyoacan, Mexico

Open Astro-Databank
External targets and signs, with longitude targets evaluated against Charting Stars internal acceptance thresholds, for Frida Kahlo
CheckExternal targetCurrent buildEvaluationReference sourceResult
Sun longitude103.383°103.375°Δ 0.007° / internal threshold 1.500°Astro-Databank Published as 13 degrees 23 minutes Cancer.JPL Horizons fixture-instant calculation check Pass
Sun signCancerCancerExact sourced signAstro-Databank Pass
Rising signLeoLeoExact sourced signAstro-Databank Pass
Inspect all externally referenced positions2 positions
Ascendant 143.510°
Current calculated values for externally referenced positions for Frida Kahlo
Body or pointEcliptic longitudeSignMotion
Sun103.375°CancerDirect

Public fixture

Carl Sagan

2/2 cited checks passFixture rating AA · source-reported AA

Calculation input

1934-11-09 at 05:05 · America/New_York

Brooklyn, NY, USA

40.6782, -73.9442

Linked source record

1934-11-09 at 17:05 · EST (UTC-05:00)

New York, New York, USA

Open Astro-Databank
External targets and signs, with longitude targets evaluated against Charting Stars internal acceptance thresholds, for Carl Sagan
CheckExternal targetCurrent buildEvaluationReference sourceResult
Sun longitude226.833°226.324°Δ 0.509° / internal threshold 1.500°Astro-Databank Published as 16 degrees 50 minutes Scorpio.JPL Horizons fixture-instant calculation check Pass
Sun signScorpioScorpioExact sourced signAstro-Databank Pass
Inspect all externally referenced positions1 positions
Current calculated values for externally referenced positions for Carl Sagan
Body or pointEcliptic longitudeSignMotion
Sun226.324°ScorpioDirect

Public fixture

Marie Curie

2/2 cited checks passFixture rating A · source-reported AA

Calculation input

1867-11-07 at 12:00 · Europe/Warsaw

Warsaw, Poland

52.2297, 21.0122

Linked source record

1867-11-07 at 12:00 · Local mean time at 21e00 (UTC+01:24)

Warsaw, Poland

Open Astro-Databank
External targets and signs, with longitude targets evaluated against Charting Stars internal acceptance thresholds, for Marie Curie
CheckExternal targetCurrent buildEvaluationReference sourceResult
Sun longitude224.583°224.575°Δ 0.007° / internal threshold 1.500°Astro-Databank Published as 14 degrees 35 minutes Scorpio.JPL Horizons fixture-instant calculation check Pass
Sun signScorpioScorpioExact sourced signAstro-Databank Pass
Inspect all externally referenced positions1 positions
Current calculated values for externally referenced positions for Marie Curie
Body or pointEcliptic longitudeSignMotion
Sun224.575°ScorpioDirect

03 · Method and limits

What this set can and cannot say

Schema v1 · birth-chart-accuracy-2026-08-14-v1 · recalculated at build time

External references

These are linked birth records, published longitudes, and sourced sign labels. References provide targets and signs; Charting Stars defines the internal acceptance thresholds retained from the engine accuracy gate. A JPL fixture-instant link independently checks a celestial position; it does not verify the birth record.

Private regression snapshots

Separate high-precision snapshots detect unexplained engine drift in CI. They are not independent evidence, are not counted as external checks, and are omitted from this page and both downloads.

Pass and Fail

Pass means the raw current result falls within the Charting Stars internal circular acceptance threshold retained from the engine accuracy gate, or matches its sourced sign. The cited source does not provide or own that threshold. Fail means that one comparison falls outside the rule. Displayed values are rounded or quantized; evaluation uses unrounded values.

Downloads

JSON preserves the nested public projection. CSV emits one row per external check and labels birth, reference, and independent sources in separate columns. Both formats are deterministic UTF-8 schema v1 representations of the same build output. Each saved file carries release ID birth-chart-accuracy-2026-08-14-v1.

Dataset-wide caveats

  1. External references supply degree-minute longitude targets or sign labels. Longitude pass/fail uses a Charting Stars internal acceptance threshold retained from the engine accuracy gate; it is defined by Charting Stars, not provided by the cited source.
  2. Precise frozen regression snapshots protect the internal engine from unexplained drift. Their stored numbers are not independent evidence and are omitted from every public record.
  3. Current longitudes are quantized downward to three decimal places for display so they stay in their raw sign interval; deltas are rounded for display. Pass or fail uses the unrounded normalized engine longitude and raw circular delta; unlisted positions carry no external claim.
  4. A JPL Horizons fixture-instant calculation link does not verify birth data. It independently checks a celestial position at the fixture-converted UTC instant, including when a birth input is disputed.
  5. fixtureRoddenRating preserves regression metadata; sourceReportedRoddenRating records the rating shown by the linked source when this dataset was prepared.
  6. Historical timezone conventions, rounded source coordinates, and disputed birth records can differ from calculation inputs; each known conflict is stated with that record.

Citation policy

Cite the reader, then retain the row-level source.

Cite Open Birth Chart Calculation Test Set, Charting Stars, release birth-chart-accuracy-2026-08-14-v1, schema v1, the canonical URL, and your access date. When discussing a specific check, keep its external source and caveat with the result. Do not describe an uncited current position or a private regression snapshot as externally checked.

https://chartingstars.com/research/birth-chart-accuracy
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