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    Re: Time and Longitude by Jupiter's moons
    From: Frank Reed
    Date: 2024 Dec 8, 09:17 -0800

    Peter M, you wrote:
    "I observed an occultation of Io once, about ten years ago. Funny story: I got the predicted time from Stellarium
    [...]
    You end up feeling very foolish in this situation. Finally it dimmed and went out. Job done."

    If, as you say, this was about ten years ago, the code in Stellarium at that time was probably low quality. It's worth knowing that the eclipse times for the Galilean satellites in Stellarium today, in 2024, appear to be dead-on, and they can be used effectively to plan observations in the cases I checked (just a few so this is not a blanket guarantee!). This seems to apply to most of the basic ephemeris and astrometric computations in Stellarium. They're much improved within the past few years.

    Frank Reed

       
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