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Looks like the adj. form should be Metidian, but needs confirmation. kwami 2005 June 29 23:53 (UTC)

Bosnian wikipedia just added it as Metida. kwami 05:54, 15 April 2006 (UTC)

[edit] Mean Radius (Orbital) and Average Distance

Great work on all these Jupiter moons. There are so many but the authors have done a great job keeping up with the latest details. Thank you! Just one question. Many of the satellite pages indicate Mean Radius or Average Distance when indicating orbital parameters. The Mean Radius or Average Distance is different from an orbit's Semi-Major Axis. What is the intent? Thanks. Tesseract501 01 June 2006.

I don't know the intent (may be for simplicity for laymen?) but mean radius is used more often than semi-major axis. I usually consider them equivalent. In fact, mean radius lacks clear definition. For instance if you consider mean potential energy it is proportional to 1/a. So in some sense semi-major asis is a mean radius. Ruslik 13:58, 29 May 2007 (UTC)

The mean radius is what is usually given for inner moons of the giant planets because their osculating semi-major axes change in complicated ways on short timescales (days, months) due to the perturbations of all the other much larger satellites around the place. The advantage of giving a mean radius is that it is a value for the size of the orbit that can be both precise and accurate without the need to specify an exact date. Deuar 23:43, 16 June 2007 (UTC)