The main source
for asteroid data of Power Age Sky Simulator is ASTORB orbit
catalog. The ASTORB catalog is produced and maintained by Dr
Edward Bowell at Lowell Observatory. ASTORB contains orbit
data for all known asteroids and is updated daily! The latest
version of the catalog can be obtained by anonymous FTP from
ftp://ftp.lowell.edu/pub/elgb/astorb.dat.gz.
Power Age Sky
Simulator package includes a program called Asteroid
Catalog Maker by
which you can make compatible asteroid catalogs for your
purposes.