---
title: "Recalculate chart angles and houses for a new location"
method: POST
path: "/api/astro/relocation-chart"
tags: ["Calculations"]
---

# Recalculate chart angles and houses for a new location

`POST /api/astro/relocation-chart`

## Request

- Base URL: `https://api.cosmicephemeris.com`
- URL: `https://api.cosmicephemeris.com/api/astro/relocation-chart`
- Auth: one of:
  - HTTP bearer
  - API key in header `x-api-key`

Preserves the exact birth instant and apparent geocentric planet/node positions, then recalculates the Ascendant, Midheaven and selected house cusps at the supplied location. This is a calculation response without interpretation or location ranking. One standard quota unit per admitted request; failed or timed-out admitted attempts are not refunded.
Historical mode uses an explicit BCE/CE date object and UT1 conventions. Its response is the versioned historical envelope, not the modern UTC envelope. Read result for calculation fields and metadata for limits and uncertainty.

## Request body

- union
  - RelocationChartRequest
    - `birth` CalculationBirthInput, required: Strict nested birth input; no unknown properties, nulls, booleans or numeric strings. Known civil time required; semantic date/DST/undefined-angle validation occurs on the server.
      - `date` string, date, required: Valid Gregorian YYYY-MM-DD local civil date, inclusive 1800-01-01 through 2200-12-31. Calendar validity and timezone conversion are checked by the server.
      - `time` string, required: HH:MM or HH:MM:SS; no offset in this field. Use timezone to select the civil-time zone.
      - `timezone` string: Valid IANA zone; UTC when omitted. Ambiguous and nonexistent civil times are rejected.
      - `lat` number, required
      - `lon` number, required
    - `location` GeographicLocation, required: Geographic coordinates in decimal degrees. The server rejects exactly -90 and +90 latitude because angles and houses are undefined at the poles.
      - `lat` union, required: WGS84 decimal latitude. JSON numbers are recommended; numeric strings are accepted by the current engine, then checked for finiteness/range. Exact poles and undefined Ascendant geometry return 400; supported successful latitude is strictly between -90 and 90. Boolean/null/object/array coordinates are invalid.
        - number
        - string
      - `lon` union, required: WGS84 decimal longitude, east positive, within [-180,180]. JSON numbers are recommended; numeric strings are accepted then checked for finiteness/range.
        - number
        - string
    - `zodiac` string, nullable: tropical or sidereal; server trims whitespace and ignores case. Omitted/null selects tropical.
    - `ayanamsa` string, nullable: Sidereal supports lahiri, raman, krishnamurti, fagan_bradley, yukteshwar, sassanian, true_chitra, true_revati, true_pushya, galactic_center_0_sagittarius, galactic_alignment_mardyks, with case/whitespace normalization; other names return 400 in sidereal mode. Omitted/null selects lahiri. Tropical mode ignores a nonempty string and outputs null. This schema describes that compatibility behavior rather than claiming every string is a supported sidereal model.
    - `house_system` 'equal' | 'whole_sign' | 'placidus'
  - HistoricalRelocationChartRequest: Explicit historical mode, 1000 BCE (BC)–2500 CE (AD). No year zero, implicit calendar, UTC or IANA zone. Preserve tool-specific mathematical, geographic and search limits; calendar/time conventions and estimated Delta-T are not certified historical accuracy.
    - `birth` HistoricalBirthInput, required
      - `date` HistoricalDate, required: Explicit civil date, 1000 BCE (BC)–2500 CE (AD); no year zero. Calendar validity is checked by the server. Available only on documented connected historical operations, with explicit UT1/fixed-offset conventions.
        - `year` integer, required
        - `era` 'BCE' | 'CE', required: Display BCE (BC) / CE (AD); API values remain BCE / CE. No year zero.
        - `month` integer, required
        - `day` integer, required
        - `calendar` 'proleptic_gregorian' | 'proleptic_julian', required: Explicit choice; applies the selected calendar rules throughout history without a regional adoption switch.
      - `time` string, required: Explicit HH:MM[:SS]; whole seconds only, no leap seconds. Normalized helper output includes seconds.
      - `timezone` string, required: Explicit UT1 or fixed offset UT1+/-HH:MM[:SS], within 14 hours. Local clock minus offset yields UT1, not UTC. No IANA timezone inference. Original offset spelling is preserved.
      - `lat` number, required
      - `lon` number, required
    - `location` object, required: Geographic coordinates in decimal degrees. The server rejects exactly -90 and +90 latitude because angles and houses are undefined at the poles.
      - `lat` union, required: WGS84 decimal latitude. JSON numbers are recommended; numeric strings are accepted by the current engine, then checked for finiteness/range. Exact poles and undefined Ascendant geometry return 400; supported successful latitude is strictly between -90 and 90. Boolean/null/object/array coordinates are invalid.
        - number
        - string
      - `lon` union, required: WGS84 decimal longitude, east positive, within [-180,180]. JSON numbers are recommended; numeric strings are accepted then checked for finiteness/range.
        - number
        - string
    - `zodiac` string, nullable: tropical or sidereal; server trims whitespace and ignores case. Omitted/null selects tropical.
    - `ayanamsa` string, nullable: Sidereal supports lahiri, raman, krishnamurti, fagan_bradley, yukteshwar, sassanian, true_chitra, true_revati, true_pushya, galactic_center_0_sagittarius, galactic_alignment_mardyks, with case/whitespace normalization; other names return 400 in sidereal mode. Omitted/null selects lahiri. Tropical mode ignores a nonempty string and outputs null. This schema describes that compatibility behavior rather than claiming every string is a supported sidereal model.
    - `house_system` 'equal' | 'whole_sign' | 'placidus'

## Response `200`

Natal reference houses and relocated chart for the same UTC instant.

- union
  - RelocationChartResponse
    - `type` 'relocation_chart', required
    - `status` 'current', required
    - `method` 'same_utc_geocentric_positions_relocated_angles', required
    - `input` object, required
    - `birth_utc` string, date-time, required: Normalized UTC timestamp; fractional seconds may be present.
    - `natal_reference` object, required
    - `relocated_chart` RelocationChart, required
      - `status` 'ok', required
      - `zodiac` 'tropical' | 'sidereal', required
      - `ayanamsa` 'lahiri' | 'raman' | 'krishnamurti' | 'fagan_bradley' | 'yukteshwar' | 'sassanian' | 'true_chitra' | 'true_revati' | 'true_pushya' | 'galactic_center_0_sagittarius' | 'galactic_alignment_mardyks', required
      - `planets` Planets, required
        - `Sun` PlanetPosition, required: Apparent geocentric JPL DE440 ecliptic position. sidereal_lon is present in sidereal mode; nakshatra is present only on the sidereal Moon.
          - `lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
          - `speed_deg_per_day` number, required: Signed tropical longitude difference over the preceding one TT day, rounded to four decimals; not an instantaneous derivative.
          - `retrograde` boolean, required
          - `tropical_lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sidereal_lon` number: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `nakshatra` Nakshatra
            - `index` integer, required
            - `name` string, required
            - `ruler` string, required
            - `pada` integer, required
            - `deg_into_nakshatra` number, required
        - `Moon` PlanetPosition, required: Apparent geocentric JPL DE440 ecliptic position. sidereal_lon is present in sidereal mode; nakshatra is present only on the sidereal Moon.
          - `lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
          - `speed_deg_per_day` number, required: Signed tropical longitude difference over the preceding one TT day, rounded to four decimals; not an instantaneous derivative.
          - `retrograde` boolean, required
          - `tropical_lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sidereal_lon` number: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `nakshatra` Nakshatra
            - `index` integer, required
            - `name` string, required
            - `ruler` string, required
            - `pada` integer, required
            - `deg_into_nakshatra` number, required
        - `Mercury` PlanetPosition, required: Apparent geocentric JPL DE440 ecliptic position. sidereal_lon is present in sidereal mode; nakshatra is present only on the sidereal Moon.
          - `lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
          - `speed_deg_per_day` number, required: Signed tropical longitude difference over the preceding one TT day, rounded to four decimals; not an instantaneous derivative.
          - `retrograde` boolean, required
          - `tropical_lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sidereal_lon` number: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `nakshatra` Nakshatra
            - `index` integer, required
            - `name` string, required
            - `ruler` string, required
            - `pada` integer, required
            - `deg_into_nakshatra` number, required
        - `Venus` PlanetPosition, required: Apparent geocentric JPL DE440 ecliptic position. sidereal_lon is present in sidereal mode; nakshatra is present only on the sidereal Moon.
          - `lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
          - `speed_deg_per_day` number, required: Signed tropical longitude difference over the preceding one TT day, rounded to four decimals; not an instantaneous derivative.
          - `retrograde` boolean, required
          - `tropical_lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sidereal_lon` number: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `nakshatra` Nakshatra
            - `index` integer, required
            - `name` string, required
            - `ruler` string, required
            - `pada` integer, required
            - `deg_into_nakshatra` number, required
        - `Mars` PlanetPosition, required: Apparent geocentric JPL DE440 ecliptic position. sidereal_lon is present in sidereal mode; nakshatra is present only on the sidereal Moon.
          - `lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
          - `speed_deg_per_day` number, required: Signed tropical longitude difference over the preceding one TT day, rounded to four decimals; not an instantaneous derivative.
          - `retrograde` boolean, required
          - `tropical_lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sidereal_lon` number: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `nakshatra` Nakshatra
            - `index` integer, required
            - `name` string, required
            - `ruler` string, required
            - `pada` integer, required
            - `deg_into_nakshatra` number, required
        - `Jupiter` PlanetPosition, required: Apparent geocentric JPL DE440 ecliptic position. sidereal_lon is present in sidereal mode; nakshatra is present only on the sidereal Moon.
          - `lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
          - `speed_deg_per_day` number, required: Signed tropical longitude difference over the preceding one TT day, rounded to four decimals; not an instantaneous derivative.
          - `retrograde` boolean, required
          - `tropical_lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sidereal_lon` number: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `nakshatra` Nakshatra
            - `index` integer, required
            - `name` string, required
            - `ruler` string, required
            - `pada` integer, required
            - `deg_into_nakshatra` number, required
        - `Saturn` PlanetPosition, required: Apparent geocentric JPL DE440 ecliptic position. sidereal_lon is present in sidereal mode; nakshatra is present only on the sidereal Moon.
          - `lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
          - `speed_deg_per_day` number, required: Signed tropical longitude difference over the preceding one TT day, rounded to four decimals; not an instantaneous derivative.
          - `retrograde` boolean, required
          - `tropical_lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sidereal_lon` number: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `nakshatra` Nakshatra
            - `index` integer, required
            - `name` string, required
            - `ruler` string, required
            - `pada` integer, required
            - `deg_into_nakshatra` number, required
        - `Uranus` PlanetPosition, required: Apparent geocentric JPL DE440 ecliptic position. sidereal_lon is present in sidereal mode; nakshatra is present only on the sidereal Moon.
          - `lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
          - `speed_deg_per_day` number, required: Signed tropical longitude difference over the preceding one TT day, rounded to four decimals; not an instantaneous derivative.
          - `retrograde` boolean, required
          - `tropical_lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sidereal_lon` number: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `nakshatra` Nakshatra
            - `index` integer, required
            - `name` string, required
            - `ruler` string, required
            - `pada` integer, required
            - `deg_into_nakshatra` number, required
        - `Neptune` PlanetPosition, required: Apparent geocentric JPL DE440 ecliptic position. sidereal_lon is present in sidereal mode; nakshatra is present only on the sidereal Moon.
          - `lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
          - `speed_deg_per_day` number, required: Signed tropical longitude difference over the preceding one TT day, rounded to four decimals; not an instantaneous derivative.
          - `retrograde` boolean, required
          - `tropical_lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sidereal_lon` number: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `nakshatra` Nakshatra
            - `index` integer, required
            - `name` string, required
            - `ruler` string, required
            - `pada` integer, required
            - `deg_into_nakshatra` number, required
        - `Pluto` PlanetPosition, required: Apparent geocentric JPL DE440 ecliptic position. sidereal_lon is present in sidereal mode; nakshatra is present only on the sidereal Moon.
          - `lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
          - `speed_deg_per_day` number, required: Signed tropical longitude difference over the preceding one TT day, rounded to four decimals; not an instantaneous derivative.
          - `retrograde` boolean, required
          - `tropical_lon` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sidereal_lon` number: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `nakshatra` Nakshatra
            - `index` integer, required
            - `name` string, required
            - `ruler` string, required
            - `pada` integer, required
            - `deg_into_nakshatra` number, required
      - `houses` RelocationHouses, required
        - `ascendant` number, required
        - `mc` number, required
        - `systems` RelocationHouseSystems, required
          - `equal` RelocationHouseSystem
            - `name` 'Equal' | 'Whole sign' | 'Placidus', required
            - `houses` Cusps, required
              - …
          - `whole_sign` RelocationHouseSystem
            - `name` 'Equal' | 'Whole sign' | 'Placidus', required
            - `houses` Cusps, required
              - …
          - `placidus` RelocationHouseSystem
            - `name` 'Equal' | 'Whole sign' | 'Placidus', required
            - `houses` Cusps, required
              - …
        - `metadata` object, required
          - `zodiac` 'tropical' | 'sidereal', required
          - `ayanamsa` 'lahiri' | 'raman' | 'krishnamurti' | 'fagan_bradley' | 'yukteshwar' | 'sassanian' | 'true_chitra' | 'true_revati' | 'true_pushya' | 'galactic_center_0_sagittarius' | 'galactic_alignment_mardyks', required
      - `aspects` NatalAspect[], required
        - `p1` 'Sun' | 'Moon' | 'Mercury' | 'Venus' | 'Mars' | 'Jupiter' | 'Saturn' | 'Uranus' | 'Neptune' | 'Pluto', required
        - `p2` 'Sun' | 'Moon' | 'Mercury' | 'Venus' | 'Mars' | 'Jupiter' | 'Saturn' | 'Uranus' | 'Neptune' | 'Pluto', required
        - `type` 'conjunction' | 'opposition' | 'trine' | 'square' | 'sextile' | 'semisextile' | 'semisquare' | 'quintile' | 'sesquiquadrate' | 'biquintile', required
        - `exact_angle` 0 | 180 | 120 | 90 | 60 | 30 | 45 | 72 | 135 | 144, required
        - `distance` number, required
        - `orb` number, required
      - `nodes` Nodes, required
        - `mean` NodePosition, required
          - `longitude` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
        - `true` NodePosition, required
          - `longitude` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
        - `south` NodePosition, required
          - `longitude` number, required: Ecliptic longitude in degrees, displayed to four decimals. Rounding of a value just below 360 can produce 360.0; do not recompute sign/pada from rounded display values.
          - `sign` 'Aries' | 'Taurus' | 'Gemini' | 'Cancer' | 'Leo' | 'Virgo' | 'Libra' | 'Scorpio' | 'Sagittarius' | 'Capricorn' | 'Aquarius' | 'Pisces', required
          - `deg_in_sign` number, required: Displayed to four decimals; rounding near the next sign can produce 30.0.
        - `note` string, required
      - `metadata` object, required
        - `note` string, required
    - `metadata` object, required
  - HistoricalRelocationChartRelocationChartResponse
    - `schema` 'cosmicephemeris-historical-calculation-v1', required
    - `status` 'historical', required
    - `type` 'relocation-chart', required
    - `input` HistoricalRelocationChartRequest, required: Explicit historical mode, 1000 BCE (BC)–2500 CE (AD). No year zero, implicit calendar, UTC or IANA zone. Preserve tool-specific mathematical, geographic and search limits; calendar/time conventions and estimated Delta-T are not certified historical accuracy.
      - `birth` HistoricalBirthInput, required
        - `date` HistoricalDate, required: Explicit civil date, 1000 BCE (BC)–2500 CE (AD); no year zero. Calendar validity is checked by the server. Available only on documented connected historical operations, with explicit UT1/fixed-offset conventions.
          - `year` integer, required
          - `era` 'BCE' | 'CE', required: Display BCE (BC) / CE (AD); API values remain BCE / CE. No year zero.
          - `month` integer, required
          - `day` integer, required
          - `calendar` 'proleptic_gregorian' | 'proleptic_julian', required: Explicit choice; applies the selected calendar rules throughout history without a regional adoption switch.
        - `time` string, required: Explicit HH:MM[:SS]; whole seconds only, no leap seconds. Normalized helper output includes seconds.
        - `timezone` string, required: Explicit UT1 or fixed offset UT1+/-HH:MM[:SS], within 14 hours. Local clock minus offset yields UT1, not UTC. No IANA timezone inference. Original offset spelling is preserved.
        - `lat` number, required
        - `lon` number, required
      - `location` object, required: Geographic coordinates in decimal degrees. The server rejects exactly -90 and +90 latitude because angles and houses are undefined at the poles.
        - `lat` union, required: WGS84 decimal latitude. JSON numbers are recommended; numeric strings are accepted by the current engine, then checked for finiteness/range. Exact poles and undefined Ascendant geometry return 400; supported successful latitude is strictly between -90 and 90. Boolean/null/object/array coordinates are invalid.
          - number
          - string
        - `lon` union, required: WGS84 decimal longitude, east positive, within [-180,180]. JSON numbers are recommended; numeric strings are accepted then checked for finiteness/range.
          - number
          - string
      - `zodiac` string, nullable: tropical or sidereal; server trims whitespace and ignores case. Omitted/null selects tropical.
      - `ayanamsa` string, nullable: Sidereal supports lahiri, raman, krishnamurti, fagan_bradley, yukteshwar, sassanian, true_chitra, true_revati, true_pushya, galactic_center_0_sagittarius, galactic_alignment_mardyks, with case/whitespace normalization; other names return 400 in sidereal mode. Omitted/null selects lahiri. Tropical mode ignores a nonempty string and outputs null. This schema describes that compatibility behavior rather than claiming every string is a supported sidereal model.
      - `house_system` 'equal' | 'whole_sign' | 'placidus'
    - `result` object, required: Complete historical calculation adapter result. Times are explicit UT1 date records, never UTC strings; derived times may include fractional seconds and years outside the input range.
    - `metadata` object, required
      - `time_standard` 'UT1', required
      - `historical_accuracy_certified` unknown, required
      - `warnings` string[], required

## Other responses

- `400`: Invalid request, malformed JSON, out-of-range date/location, unknown model, invalid timezone or ambiguous/nonexistent clock-change time. Invalid attempts reaching quota reservation consume one unit.
- `401`: Missing, invalid, revoked API key or unavailable activated key owner. Dashboard cookies do not authenticate calculation routes.
- `403`: Origin not allowed by production CORS policy. Server-to-server requests can omit Origin.
- `429`: Monthly quota exhausted, per-user two-request concurrency reached, or nginx rate/connection admission refused. Retry-After: 2 is sent for application per-user concurrency only, not a promise that monthly quota resets in two seconds.
- `502`: Engine unavailable, unsuccessful internal server response or invalid upstream JSON. No engine internals are exposed.
- `503`: Four-request global calculation pool full (Retry-After: 2), maintenance or upstream service unavailable.
- `504`: Application engine timeout: 15 seconds normally; planetary events, house ingresses, aspect windows, event calendar, eclipse geometry, electional search, and event-rule search use 30 seconds; Nakshatra Timeline plus the explicitly enumerated readiness, robustness, location, uncertainty, and electional-audit family use 60 seconds. Timer includes response-body parsing; an admitted timeout consumes quota.

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[API](https://skmtc.dev/cosmicephemeris/apis/cosmic-ephemeris-calculation-api.md) · [All operations](https://skmtc.dev/cosmicephemeris/apis/cosmic-ephemeris-calculation-api/llms.txt) · [OpenAPI document](https://skmtc.dev/cosmicephemeris/apis/cosmic-ephemeris-calculation-api/revisions/f041e924cea3?raw)