NASA ADS

Overview

The NASA ADS API (Harvard ADS) searches the astronomy/astrophysics literature — 15M+ papers with abstracts, citations, and metrics. Auth is an OAuth token (an invalid token returns 401, verified).

Quick Start

Get a token at ui.adsabs.harvard.edu (Account → API Token), then (replace YOUR_TOKEN):

curl "https://api.adsabs.harvard.edu/v1/search/query?q=star&rows=3" \
  -H "Authorization: Bearer YOUR_TOKEN"

{
  "response": {
    "numFound": 123456,
    "docs": [
      { "title": ["Stellar evolution"], "author": ["Smith, J."], "year": "2024", "bibcode": "2024ApJ...123..456S" }
    ]
  }
}

Authentication

• Register at ui.adsabs.harvard.edu → Account → API Token.
• Send as Authorization: Bearer YOUR_TOKEN (missing → 401, verified).

Rate Limits & Notes

• Free: generous limits for registered users (check the docs).
• Search syntax: q= with ADS query language (author, year, abstract fields).
• The API also serves metrics, citations, and fulltext export.
• bibcode is the stable paper identifier.

FAQ

Is NASA ADS free? Yes — free for registered users with rate limits.

How do I get a token? ui.adsabs.harvard.edu → Account → API Token.

What’s a bibcode? The stable identifier (e.g. 2024ApJ...123..456S).