NASA ADS
FreeLiveLast verified 24 Sept 2026
Search astronomy and physics research literature: paper metadata, abstracts, and citation data.
Example request
curl -H 'Authorization: Bearer $API_KEY' 'https://api.adsabs.harvard.edu/v1/search/query?q=star'
Free tier, in plain English
Free after creating an ADS account and generating a personal token; each endpoint has its own daily quota visible in the response headers.
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