Chronicling America vs Spaceflight News

Chronicling America is the Library of Congress's searchable archive of historic U.S. newspaper pages published through 1963, built from the National Digital Newspaper Program. As of August 2025 its data moved fully onto the general loc.gov JSON/YAML API, retiring the old chroniclingamerica.loc.gov endpoints in favor of structured search, batch, and full-text access — no API key is required, though heavy use should self-throttle.

Spaceflight News API is a free, keyless aggregator of space and astronomy news, articles, blogs, and reports pulled from NASA, ESA, and dozens of other spaceflight outlets, currently indexing more than 35,000 articles. The v4 API is fully open — no signup or API key needed — and returns paginated JSON with count/next/previous fields, plus a public OpenAPI/Swagger reference at its /v4/docs endpoint.