It's closer and we have so much evidence already on other phases of water (vapor and ice). This excites people since it will be the closest source of water outs

It's closer and we have so much evidence already on other phases of water (vapor and ice). This excites people since it will be the closest source of water outside of Earth and could be the motivation to send Man over there. Europa is so much further and just to look for the fish would require equipment to penetrate the surface for the off chance there is water underneath.