From 34db00ce0c443db7bf4a86f3a7eb3f65ae6f763f Mon Sep 17 00:00:00 2001
From: CycleCalcs <293662008+cyclecalcs@users.noreply.github.com>
Date: Wed, 12 Aug 2026 10:29:21 -0400
Subject: [PATCH] Add CycleCalcs to Astronomy APIs

---
 README.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/README.md b/README.md
index 37aa21b..6503aa2 100644
--- a/README.md
+++ b/README.md
@@ -53,6 +53,7 @@ A curated list of space-related code, APIs, data, and other resources.
 
 * [AstroBin API](http://www.astrobin.com/help/api/) - AstroBin is an image hosting website specifically targeted to astrophotographers. Its API offers a basic set of RESTful endpoints. Currently the API is read-only, and  allows you to get data about images, and perform basic searches.
 * [astrometry.net](http://astrometry.net/) - "If you have astronomical imaging of the sky with celestial coordinates you do not know—or do not trust—then Astrometry.net is for you. Input an image and we'll give you back astrometric calibration meta-data, plus lists of known objects falling inside the field of view."
+* [CycleCalcs](https://www.cyclecalcs.com/api.html) - A read-only astronomy API returning interpreted answers rather than raw ephemeris: moon phase and illumination, sunrise, sunset and twilight, planet positions and visibility, rise and set times, eclipses, lunar nodes and libration, seasons, retrograde stations and conjunctions. No key required for the free tier, CORS enabled, and every response states its reference frame, epoch, time scale and refraction model. Also published as an MCP server and as reproducible CC0 datasets covering 1700-2200 (DOI 10.5281/zenodo.21905242).
 * [Open Astronomy Catalog API](https://astrocats.space/) - The Open Astronomy Catalog API (OACAPI) offers a lightweight, simple way to access data available via the Open Astronomy Catalogs (e.g. the Open Supernova, Tidal Disruption, Kilonova, and Fast Stars Catalogs).
 * [SpaceXDB-Api](https://github.com/R4yGM/SpaceXDB-Api) - [SpaceXDB](https://www.spacexdb.cf) is a website containing SpaceX launch information and telemetry.