We could send a lander to drop a drilling probe through the kilometers-thick ice or attempt to find a huge fissure to access the sub-surface ocean.

我们可以发射一个着陆器，向该星球投放一个有钻头的探测器，钻通其几公里厚的冰面；或者尝试去寻找一个巨大的裂缝进入地下海洋。