John Carmichael wrote: > I usually don't write two different letters to the list on the same day, but > could'nt resist the following question in view of today's landing on Mars. > > What would the martian analemma and Equation of Time look like?
Martian and other non-terrestrial analemmas were discussed in: David A. Harvey, "The Analemmas of the Planets", Sky & Telescope, vol. 63 (1982), 237-239. The Martian analemma is rather simple compared with the terrestrial case and resembles an asymmetrical droplet. Even more boring are the elliptical analemmas of Mercury, Venus and Jupiter. 8-shaped analemmas such as the terrestrial case are found on Saturn, Uranus, Neptune and Pluto. That of Saturn barely manages to form an 8 and those of Uranus and Pluto exhibit large north-south spans of 164 and even 180 degrees. These calculations were based on the planetary rotation parameters as they were known at that time and can probably be improved somewhat for the outermost planets as better determinations have become available. Also have a look at: http://www.analemma.com/ ================================================================ * Robert H. van Gent * Tel/Fax: 00-31-30-2720269 * * Zaagmolenkade 50 * E-mail: [EMAIL PROTECTED] * * 3515 AE Utrecht * Home page (under construction): * * The Netherlands * http://www.fys.ruu.nl/~vgent/ * ================================================================