OpenEI
Linked energy information on hundreds of topics crowdsourced from industry and government agencies.
Archaeology Data Service
Certified repository for Archaeology data
MAST: Barbara A. Mikulski Archive for Space Telescopes
new MAST: Barbara A. Mikulski Archive for Space Telescopes
USVAO: US Virtual Astronomical Observatory
US Virtual Astronomical Observatory
GEOSS Portal
Earth science data
NCEI
Weather, climate, coasts, oceans, and geophysics etc