Multiple astronomy data sources
Access the world's Open Access research papers
Global Biodiversity Information Facility
Space Telescope News Releases
Access millions of museum specimens from organizations around the world
High Energy Physics info. system
Integrated Taxonomic Information System
Spaceflight launches and events database
Curated experimental data for materials science
Asterank.com Information
API for getting APOD (Astronomy Image of the Day) images along with metadata
Symbolic and Arithmetic Math Calculator
Number of the day, random number, number facts and anything else you want to do with numbers
ISS astronauts, current location, etc
Repository and archive for study designs, research materials, data, manuscripts, etc
Query next satellite passes above you
A free, open, dataset about research and scholarly activities
Company, vehicle, launchpad and launch data
Sunset and sunrise times for a given latitude and longitude
Earthquakes data real-time
Water quality and level info for rivers and lakes
World Data