A
APIs Score

arcsecond.io API

Beginner's Pick Science & Math / No Auth Required Beginner HTTPS
Free to Use Varies (check documentation)
82 A
Metadata Score 0 50 100 Metadata estimate · not endpoint-tested
Visit Official Site Compare Alternatives

Overview

arcsecond.io is a free astronomy API that aggregates data from multiple space databases, including stars, planets, exoplanets, and observing sites. You can query celestial objects by name or coordinates and get rich scientific data back. No API key is required, making it perfect for beginners wanting to explore astronomy data.

Beginner Tip

Try querying a well-known object like "Mars" or "Sirius" first to see the data structure before building more complex queries. The API returns JSON that is easy to parse in any language.

Available Data

Use case: Integrate multiple astronomy data sources data into web and mobile applications
arcsecond.io data via REST API

Example Response

JSON Response 
{
  "title": "Astronomy Picture of the Day",
  "date": "2025-01-15",
  "explanation": "A stunning nebula captured by the James Webb Telescope...",
  "url": "https://apod.nasa.gov/apod/image/...",
  "media_type": "image"
}

Field Reference

name Common or catalogue name of the celestial object.
right_ascension Right ascension coordinate in degrees.
declination Declination coordinate in degrees.
object_types List of classifications for the object (e.g., star, planet, galaxy).
aliases Alternative names or catalogue designations for the object.

Implementation Example

Request 
const url = "https://api.arcsecond.io/";
const response = await fetch(url);
if (!response.ok) throw new Error(`Request failed: ${response.status}`);
const data = await response.json();
console.log(data);

What Can You Build?

Note: These code examples are AI-generated and unverified. Always refer to the official API documentation for accurate usage.

Common Errors & Troubleshooting

404 Not Found The object name was misspelled or is not in the database.
✓ Try alternate names or spellings (e.g., "alpha-centauri" instead of "Alpha Centauri").
Empty results array The search query did not match any catalogued objects.
✓ Broaden your search term or use a standard astronomical designation like an HD or NGC number.
CORS error in browser Direct browser requests to the API may be blocked depending on origin.
✓ Proxy the request through your backend server to avoid CORS issues.

Metadata Score Breakdown

Estimated from metadata — endpoint not independently tested

This score is estimated from observable metadata — HTTPS support, authentication model, declared CORS, and documentation reachability — because the API requires authentication or exposes no publicly testable endpoint. The five-signal breakdown is only shown for live-tested APIs.

Metadata estimate · endpoint not independently tested

How is this scored? →

Technical Specifications

Auth No Auth
HTTPS REQUIRED
CORS UNKNOWN
Category Science & Math
Difficulty Beginner
Verified: 2026-04-04

Related Tags

#science-and-math

Similar APIs

View All →

arXiv

⚠ Unavailable
0 F
Est.

arXiv provides programmatic access to curated research-sharing platform: physics, mathematics, quantitative finance, and economics via REST API.

No Auth Beginner HTTPS 71ms

GBIF

⭐ Beginner's Pick
82 A
Measured

GBIF (Global Biodiversity Information Facility) is a free, open API providing access to hundreds of millions of species occurrence records from around the world.

No Auth Beginner HTTPS 871ms

iDigBio

74 B
Measured

iDigBio is a free API that gives you access to millions of digitized natural history museum specimens from institutions across the United States and beyond.

No Auth Beginner HTTPS 3318ms

inspirehep.net

85 A
Measured

INSPIRE-HEP is a free REST API for the High Energy Physics literature database, covering papers, authors, institutions, conferences, and experiments in particle physics.

No Auth Beginner HTTPS 2966ms

isEven (humor)

⭐ Beginner's Pick
95 A+
Measured

isEven is a humorous free API that tells you whether a number is even or odd.

No Auth Beginner HTTPS 445ms