Open Notify
ISS astronauts, current location, etc
Repository and archive for study designs, research materials, data, manuscripts, etc.
Open Science Framework API is a free Science & Math API that requires no API key, is served over HTTPS and has unconfirmed CORS support.

Unified API suite · now live
Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
ISS astronauts, current location, etc
Sub-arcsecond planetary positions, natal charts, transits, and Human Design from NASA JPL DE440
Facts pertaining to the physical science of Oceanography
Yes. The Open Science Framework API is listed in the Science & Math category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
No. The Open Science Framework API requires no authentication, so you can start making requests without signing up.
CORS support for the Open Science Framework API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The Open Science Framework API is served over HTTPS, so it's safe to use in production.