Ganymede seems to own quite a few ocean layers, stacked up with levels of ice between them. The best degree of ice will be the crust, which could be about 150 kilometers (about 90 miles) thick. The bottom ocean amount can be 800 kilometers (about five hundred miles) down below https://josuecfdyv.jts-blog.com/33691500/a-secret-weapon-for-best-moons