Early NASA Space Program

"For the smaller craters, it's like if you're filling a bucket, eventually your bucket gets full, but if you keep pouring cups of water into the bucket, you can't tell how many cups of water beyond full you've gone. Looking at the larger craters at the subsurface might give us insight, because that 'bucket' isn't full yet," Dr. Soderblom added. "For the smallest craters that we're looking at, we think we're starting to see where the Moon has gone through so much fracturing that it gets to a point where the porosity of the crust just stays at some constant level. You can keep impacting it and you'll hit regions where you'll increase porosity here and decrease it there, but on average it stays constant," Dr. Soderblom continued to explain to the press on September 10, 2015. Saturn is the smaller of the two gas-giant planets, twirling around our Sun, in the outer regions of our Solar System--far from the delightful warmth of our lovely incandescent roiling gas-ball of a Star. Jupiter is the larger of the duo of gas-giants dwelling in our Solar System, as well as the largest planet in our Sun's bewitching family, which is composed of eight major planets, an assortment of moons and moonlets, and a rich menagerie of smaller objects. Saturn is the second-largest planet in our Solar System--and probably the most beautiful.