Orthosie is a moon of Jupiter. It was only discovered in 2001, and is a very small moon, only 2 km in diameter. It is part of the Ananke Group of moons that orbit Jupiter.
Orthosie is from Greek Mythology. Orthosie was one of the Horae, which were the Greek goddesses of the seasons, and nature. Orthosie was the goddess of prosperity. Orthosie does not appear in the Social Security Administration's name database.
I like this name, but I think most people would have difficulty pronouncing it. You can find the pronunciation here.