english: We don't know just how thick it is, probably miles thick, so it's very expensive and very difficult to go down there -- send down your submarine or whatever it is -- and explore.
non_english: Nevieme ešte presne ako hrubý, pravdepodobne kilometre, je teda veľmi drahé a náročné dostať sa tam dole -- poslať tam dole ponorku, či niečo iné -- a skúmať.