This elliptical thing cleared me about who was the responsible for Dezo eclipse (which also shows us Dezo and Parma doesn’t have the same "planet year").
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In PS4 there is no sign that the planet gets an eclipse anymore (I’m pretty sure Dezorians never mention that phenomenon). But in other Phantasy Stars we read…
PS1: «An eclipse occurs on this planet once every hundred years. A torch lit during an eclipse is called an "Eclipse Torch" and is regarded as holy by the Dezorians.»
PS2: «The reason the accident happened on the day of a solar eclipse was because the Palm people didn't pray.»
Actually in PS4 they only mention 1000 years (instead of 100):
«Supposedly there is this holy flame at the Gumbious Temple that protects us. It's said that it has been burning without fail for a thousand years.»
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If a torch is lit every time Dezo has an eclipse, this means the last one was a thousand years ago (in PSII).
So I guess we can assume Palma was the planet witch provoked (every 100 years) the eclipse in Dezolis.
According to my calculus "1 year (Parma) = 100 or 200yrs Dezo"