---
title: "Calculate Pro sidereal nakshatra/pada residences"
method: POST
path: "/api/astro/nakshatra-timeline"
tags: ["Pro timeline"]
---

# Calculate Pro sidereal nakshatra/pada residences

`POST /api/astro/nakshatra-timeline`

## Request

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

Gap-free returned residence coverage with numerically refined boundaries. Hourly discovery can miss an out-and-back departure/re-entry entirely between samples. Boundary solver resolution is not physical absolute-time accuracy; this is not an exhaustive station/event finder.

Each admitted request reserves one monthly usage unit before route validation or engine work; failed or timed-out admitted attempts are not refunded. Do not automatically retry.
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
  - TimelineRequest: Pro only. Unknown fields are ignored; step_seconds is not a public control and is not passed to the engine. Each admitted request reserves one timeline unit, independent of range.
    - `planet` string, required: One of sun, moon, mercury, venus, mars, jupiter, saturn, rahu, ketu. Case/whitespace are normalized. Rahu/Ketu are mean lunar nodes.
    - `start_utc` string, date-time, required: ISO 8601 timestamp with Z or an explicit numeric UTC offset. Prefer RFC 3339, e.g. 2026-01-01T00:00:00Z. Naive local timestamps are rejected. The server normalizes offsets to UTC before comparing ordering, duration and the inclusive 1800-01-01 through 2200-12-31 UTC-date bounds.
    - `end_utc` string, date-time, required: ISO 8601 timestamp with Z or an explicit numeric UTC offset. Prefer RFC 3339, e.g. 2026-01-01T00:00:00Z. Naive local timestamps are rejected. The server normalizes offsets to UTC before comparing ordering, duration and the inclusive 1800-01-01 through 2200-12-31 UTC-date bounds.
    - `ayanamsa` string, required: Required even though chart endpoints default it. One of lahiri, raman, krishnamurti, fagan_bradley, yukteshwar, sassanian, true_chitra, true_revati, true_pushya, galactic_center_0_sagittarius, galactic_alignment_mardyks; case/whitespace are normalized.
  - HistoricalTimelineRequest: 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.
    - `planet` string, required: One of sun, moon, mercury, venus, mars, jupiter, saturn, rahu, ketu. Case/whitespace are normalized. Rahu/Ketu are mean lunar nodes.
    - `ayanamsa` string: Required even though chart endpoints default it. One of lahiri, raman, krishnamurti, fagan_bradley, yukteshwar, sassanian, true_chitra, true_revati, true_pushya, galactic_center_0_sagittarius, galactic_alignment_mardyks; case/whitespace are normalized.
    - `start` HistoricalDateTime, required: Shared historical input contract; parsing alone does not enable a calculation route. Derived calculation records can include fractional seconds and are not this input type.
      - `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.
    - `end` HistoricalDateTime, required: Shared historical input contract; parsing alone does not enable a calculation route. Derived calculation records can include fractional seconds and are not this input type.
      - `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.
    - `step_seconds` unknown

## Response `200`

Successful calculation. Field nesting is specific to this route.

- union
  - TimelineResponse: Gap-free returned residence coverage with numerically refined boundaries. Hourly discovery can miss an out-and-back departure/re-entry entirely between samples. Boundary solver resolution is not physical absolute-time accuracy; this is not an exhaustive station/event finder.
    - `planet` 'sun' | 'moon' | 'mercury' | 'venus' | 'mars' | 'jupiter' | 'saturn' | 'rahu' | 'ketu', required
    - `zodiac_used` 'sidereal', required
    - `ayanamsa_used` 'lahiri' | 'raman' | 'krishnamurti' | 'fagan_bradley' | 'yukteshwar' | 'sassanian' | 'true_chitra' | 'true_revati' | 'true_pushya' | 'galactic_center_0_sagittarius' | 'galactic_alignment_mardyks', required
    - `start_utc` string, date-time, required: Normalized UTC timestamp; fractional seconds may be present.
    - `end_utc` string, date-time, required: Normalized UTC timestamp; fractional seconds may be present.
    - `step_seconds` unknown, required
    - `segments` TimelineSegment[], required
      - `planet` 'sun' | 'moon' | 'mercury' | 'venus' | 'mars' | 'jupiter' | 'saturn' | 'rahu' | 'ketu', required
      - `ayanamsa` 'lahiri' | 'raman' | 'krishnamurti' | 'fagan_bradley' | 'yukteshwar' | 'sassanian' | 'true_chitra' | 'true_revati' | 'true_pushya' | 'galactic_center_0_sagittarius' | 'galactic_alignment_mardyks', required
      - `nakshatra_index` integer, required
      - `nakshatra_name` string, required
      - `pada` integer, required
      - `start_utc` string, date-time, required: Normalized UTC timestamp; fractional seconds may be present.
      - `end_utc` string, date-time, required: Normalized UTC timestamp; fractional seconds may be present.
      - `sidereal_longitude_start` number, required
      - `sidereal_longitude_end` number, required
      - `retrograde` boolean, required: Net direction across this returned residence segment, not a guarantee of uniform motion throughout a station-spanning segment.
  - HistoricalTimelineResponse
    - `schema` 'cosmicephemeris-historical-calculation-v1', required
    - `status` 'historical', required
    - `type` 'nakshatra-timeline', required
    - `input` HistoricalTimelineRequest, 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.
      - `planet` string, required: One of sun, moon, mercury, venus, mars, jupiter, saturn, rahu, ketu. Case/whitespace are normalized. Rahu/Ketu are mean lunar nodes.
      - `ayanamsa` string: Required even though chart endpoints default it. One of lahiri, raman, krishnamurti, fagan_bradley, yukteshwar, sassanian, true_chitra, true_revati, true_pushya, galactic_center_0_sagittarius, galactic_alignment_mardyks; case/whitespace are normalized.
      - `start` HistoricalDateTime, required: Shared historical input contract; parsing alone does not enable a calculation route. Derived calculation records can include fractional seconds and are not this input type.
        - `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.
      - `end` HistoricalDateTime, required: Shared historical input contract; parsing alone does not enable a calculation route. Derived calculation records can include fractional seconds and are not this input type.
        - `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.
      - `step_seconds` unknown
    - `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.
- `402`: Timeline requires effective Pro entitlement; admission is refused before quota reservation.
- `403`: Origin not allowed by production CORS policy. Server-to-server requests can omit Origin.
- `404`: Wrong/case-variant/noncanonical or trailing-slash route; public paths have no version prefix.
- `413`: Request exceeds the body limit; gateway JSON is capped at 128 KiB. Edge failures may be HTML.
- `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.
- `500`: Bounded gateway/database/internal failure. An admitted attempt can still consume quota.
- `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.

---

[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)