So let's look at the most important thing on this list first. Water is the basis of all life as we know it, and it's far too heavy for us to carry water from the Earth to Mars to live, so we have to find water if our life is going to succeed on Mars. And if you look at Mars, it looks really dry, it looks like the entire planet is a desert. But it ______ that it's not. The soil alone on Mars ______up to 60 percent water. And a number of ______that we still have flying around Mars have shown us -- and by the way, that's a real photograph -- that lots of craters on Mars have a sheet of water ice in them. It's not a bad place to start a colony.