“Chemical markers in the water of our oceans suggest that most of the water came from asteroids. Recent observations hint that ice, and possibly even liquid water, exists in the interiors of asteroids and comets.”
Venus may have been our solar system’s first ocean world.
Billions of years ago, Mars lost its protective global magnetic field and has lost approximately 87 percent of the water it had billions of years ago. Most of the remaining water on Mars is frozen in the ice caps or trapped beneath the soil
Moons of Jupiter Europa , Ganymede and Callisto have salty waters underground their surface protected by icy layers and so do the Moons of Saturn : Titan, Enceleadus and Mimas.