Aerospace Database,
this site, produced by the American Institute of Aeronautics and Astronautics,
is "the best source of aerospace bibliographic information."
AstroEd
- Astronomy Education Resources, includes links to sites arranged under
curriculum materials and online courses, newsletters and articles, and
more.
Gazetteer
of Planetary Language, a contemporary searchable database of names
that have been used in our planetary system, especially for people wishing
to assign new names (from Choice, Supplement 37)