canonical: https://jentic.com/apis/arcsecond.io/arcsecond # Arcsecond Astronomy API Jentic publishes the only available OpenAPI specification for Arcsecond Astronomy API, keeping it validated and agent-ready. Arcsecond is a unified REST API for world-wide astronomy data spanning exoplanets, observing sites, telescopes, instruments, observations, satellites, and astronomical objects. The API is used by amateur and professional astronomy tooling, planetarium software, and research dashboards. Authentication is via a token-based scheme, with separate registration and login endpoints for issuing tokens. ## For AI agents Look up exoplanets, observing sites, telescopes, satellites, and astronomical objects from a unified astronomy data API. ## Scope Does not handle live telescope control, image processing, or weather forecasting - use for astronomy catalogue lookups only. ## Capabilities - Look up exoplanets by name and list known planetary systems - Resolve an astronomical object by name and return its catalogued properties - List worldwide observing sites and fetch site detail by UUID - List telescopes and pair them with their host observing site - Register a user and exchange credentials for a token used on subsequent calls ## Use cases ### Exoplanet Lookup for Educational Tools Surface known exoplanets and their host-star data inside an educational app or planetarium-style tool. Schools and amateur astronomy products use Arcsecond as a single source for exoplanet catalogues without scraping multiple research databases. GET /exoplanets/ lists the catalogue and GET `/exoplanets/{name}`/ returns the detail record for a specific planet. Example prompt: Call GET `/exoplanets/{name}`/ with the user's planet name and return the host star, orbital period, and discovery year. ### Observing-Site Directory for Trip Planning Plan an astronomy trip by looking up observing sites, their coordinates, and their associated telescopes. Astronomy tour operators and dark-sky tools use Arcsecond to render maps and pick a site that matches the user's altitude or hemisphere preferences. The observing-sites and telescopes endpoints expose this directory. Example prompt: Call GET /observingsites/ and filter by the user's hemisphere, then return the matching sites and their telescopes. ### Astronomical Object Resolution Resolve a free-text astronomical object name into a catalogued record with coordinates and metadata. Stargazing apps use this to translate a user's typed query into a record they can render in a sky chart. GET `/objects/{name}`/ accepts the canonical or common name and returns the resolved object. Example prompt: Call GET `/objects/{name}`/ with the user's typed name and return the resolved object's coordinates and catalogue identifier. ### AI Agent Astronomy Assistant via Jentic An assistant agent answering 'what is Kepler-22b' or 'where is the largest telescope in Chile' can call Arcsecond through Jentic to ground its answers in real catalogue data. The agent searches for the lookup operation, loads the schema, and executes the call without managing the token. Jentic resolves the token from its credential vault. Example prompt: Use Jentic search 'look up an exoplanet', load the schema for GET `/exoplanets/{name}`/, then execute with the user's planet name and return the catalogued properties. ## Key endpoints | Method | Path | Description | | --- | --- | --- | | POST | `/auth/login/` | Log in and receive an auth token | | POST | `/auth/register/` | Register a new user | | GET | `/exoplanets/` | List all exoplanets | | GET | `/exoplanets/{name}/` | Get a specific exoplanet | | GET | `/objects/{name}/` | Resolve an astronomical object by name | | GET | `/observingsites/` | List observing sites worldwide | | GET | `/observingsites/{uuid}/` | Get a specific observing site | | GET | `/telescopes/` | List telescopes | ## Key resources - **Auth** — Register a user and log in to obtain an authentication token - **Exoplanets** — List exoplanets and fetch detail by name - **Objects** — Resolve an astronomical object by name - **Observing Sites** — List observing sites worldwide and fetch detail by UUID - **Telescopes** — List telescopes and their host site associations - **Observations** — Access observation records linked to objects and sites - **Satellites** — List satellites tracked in the Arcsecond database ## Why Jentic - **Setup:** Wiring Arcsecond by hand means exchanging credentials at its login endpoint for an auth token and then paging its exoplanet, object, and observing-site catalogues yourself. Through Jentic you install once, import the Arcsecond Astronomy API from the API Directory, store the token once, and your agent calls it. - **Permission scoping:** Arcsecond puts the object name or site uuid in the URL path (`/exoplanets/{name}`/, `/observingsites/{uuid}`/), so a rule can pin your agent to reading specific catalogue entries. You choose the operations it may call, so account operations like register are not included unless you add them. - **Credential handling:** Your Arcsecond auth token is stored once, encrypted, by your own Jentic One instance and injected at execution time. It never enters the agent's prompt, logs, or context. - **Discovery method:** Agents search Jentic by intent such as 'look up an exoplanet', and Jentic returns the matching Arcsecond operation with its input schema so the agent calls the right endpoint without browsing docs. ## Related APIs - **NASA APOD API** — NASA's Astronomy Picture of the Day pairs naturally with Arcsecond's catalogue lookups for educational astronomy apps. - **NASA NeoWs API** — Near-Earth object tracking pairs with Arcsecond's deeper catalogue of telescopes and observing sites. - **WeatherAPI** — Astronomy trip planning needs cloud-cover and seeing forecasts alongside the Arcsecond observing-site directory. ## FAQ ### Why is there no official OpenAPI spec for Arcsecond Astronomy API? Arcsecond does not publish an OpenAPI specification on api.arcsecond.io. Jentic generates and maintains this spec so that AI agents and developers can call Arcsecond Astronomy API via structured tooling. It is validated against the live API and kept up to date. Get started with Jentic One, the self-hosted execution layer. ### What authentication does the Arcsecond API use? Arcsecond uses token-based authentication. Register via POST `/auth/register`/ or log in via POST `/auth/login`/ to receive a token, then send it on subsequent requests. Through Jentic, the token is stored encrypted in the vault and never enters the agent's context. ### Can I list every exoplanet catalogued in Arcsecond? Yes. Call GET /exoplanets/ to list the catalogue, and GET `/exoplanets/{name}`/ to fetch the detail record for a specific exoplanet including its host star and orbital characteristics. ### How do I find a telescope or observing site? Use GET /telescopes/ to list telescopes and GET /observingsites/ or GET `/observingsites/{uuid}`/ to look up a specific site. Telescopes carry a reference to their host site so you can resolve the pair in two calls. ### What are the rate limits for the Arcsecond API? The OpenAPI spec does not declare explicit rate limits. Arcsecond applies per-token fair-use limits - sustained traffic above a few requests per second can be throttled. Contact Arcsecond for higher quotas in production workloads. ### How do I look up an exoplanet through Jentic? Install Jentic with pip install jentic, search for 'look up an exoplanet', load the schema for GET `/exoplanets/{name}`/, then execute with the planet name. Jentic injects the auth token automatically. ### Can I limit what my agent is allowed to do with the Arcsecond Astronomy API? Yes. Jentic One is self-hosted, so your own rules decide which Arcsecond operations and credentials your agent may use. You can restrict it to read-only catalogue lookups such as GET `/exoplanets/{name}`/ and GET `/observingsites/{uuid}`/, pinning it to specific entries because the object name or site UUID sits in the URL path. Account operations like POST `/auth/register`/ stay out of reach unless you explicitly grant them.