I believe it's the choice of kanji that makes the difference. All the senshi have the kanji for their planet in their family names, as I understand it. Likewise the "Chi" in "Chiba Mamoru" is the "Chi" for "Earth".
-- Bob
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It's spelt "Frodo Baggins" but it's pronounced "Throat-wobbler Mangrove."
-- Bob
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It's spelt "Frodo Baggins" but it's pronounced "Throat-wobbler Mangrove."