© O.Hainaut / ESO-Chile (1992)
© O.Hainaut / ESO-Germany (1993)
© O.Hainaut / K. Meech -- IfA/UHawaii and TOPS Workshop (1997)
© O.Hainaut / ESO-Chile (2001)

The observatory and city list comes mostly from that included in XEphem, the great interactive astronomical ephemeris program for X-Windows, http://www.ClearSkyInstitute.com/xephem ecdowney@ClearSkyInstitute.com, with personal additions and deletions. Any errors in the current list is mine. First and foremost, many thanks to my wonderful wife, Kathy, for her unwavering trust, acceptance and love.

Several subroutines come from "Astronomical Formulae for Calculators" by Jean Meeus. Richmond, Va., U.S.A., Willmann-Bell, (c) 1982.

Plots performed in SuperMongo, by Robert Lupton and Patricia Monger, http://www.astro.princeton.edu/~rhl/sm/.