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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Planetarium Software
From: Frank Reed
Date: 2005 Apr 16, 01:51 EDT
From: Frank Reed
Date: 2005 Apr 16, 01:51 EDT
Alex E wrote: "How do you produce the almanac entry? Did you download the almanac/ephemerides data (from a US gov website?) or you compute them?" I don't think anyone has mentioned Solex yet. It's a wonderful software project created by Italian chemist Aldo Vitagliano who also happens to be a specialist in celestial mechanics (a high-end hobbyist, rather like Jean Meeus). Solex does full-blown numerical integrations of the Solar System and can produce highly accurate results covering tens or hundreds of thousands of years. Also it's set up so that you can easily export positional data in various coordinate systems and formats or even output osculating orbital elements. Some of you may recall that there was a little disagreement in early reports back in 2002/03 over how long it had been since Mars was as close to the Earth as it would be in August 2003. Jean Meeus using the usual analytical approach to ephemeris data had come up with a date of more than 70,000 years ago. Later a figure closer to 59,000 years was in the press. This revision was generated by Vitagliano's Solex, following a request by Meeus. Here's a brief story that mentions the issue from the space.com archives: http://www.space.com/spacewatch/mars_10_closest_030822.html Go here to download Solex: http://chemistry.unina.it/~alvitagl/solex/ It's free. -FER http://www.HistoricalAtlas.com/lunars
