The sole moon of one of Sol's moons?

SOL-ar. We get the word solar from Sol. Using that logic, any other planetary system would be a star-ar system. Colloquially, sure, since we all get what you're saying, but to scientists, who love to "achtchually.." people, they need to be very technically correct

I think the theory is that if you go deep enough, it gets warmer due to interior heating. Plus the added pressure that deep could help in melting the water. I think you may also not be considering that salty water changes phases differently than pure water